From f78aa930d6bd089426742bc56a202c46e0bb95a9 Mon Sep 17 00:00:00 2001
From: Adrian Scripca <benishor@gmail.com>
Date: Tue, 16 May 2023 14:07:29 +0300
Subject: [PATCH] Starting to refactor the GUI

---
 CMakeLists.txt |    2 +-
 main.cpp       | 1115 +-----------------------------------------------
 sender_app.cpp | 1029 ++++++++++++++++++++++++++++++++++++++++++++
 sender_app.h   |  144 +++++++
 4 files changed, 1177 insertions(+), 1113 deletions(-)
 create mode 100644 sender_app.cpp
 create mode 100644 sender_app.h

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 9a55905..b3fb063 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -26,7 +26,7 @@ set(CMAKE_CXX_VISIBILITY_PRESET hidden)
 
 set(TESTS grbl_test.cpp heightmap_test.cpp)
 set(TERJE terje/gcode.cpp terje/gcode.h terje/gcode_parser.h terje/gcode_parser.cpp terje/machine.h terje/machine.cpp terje/grbl.h terje/grbl.cpp terje/comms.h terje/comms.cpp terje/telnet.h terje/telnet.cpp terje/measure_view_model.h terje/measure_view_model.cpp)
-set(SENDER_GRBL_SRC grbl.h grbl.cpp grbl_communication.h grbl_communication.cpp grbl_machine.h grbl_machine.cpp string_utils.h render.h render.cpp heightmap.h heightmap.cpp gcode_parser.h gcode_parser.cpp gcode_commands.h gcode_commands.cpp)
+set(SENDER_GRBL_SRC grbl.h grbl.cpp grbl_communication.h grbl_communication.cpp grbl_machine.h grbl_machine.cpp string_utils.h render.h render.cpp heightmap.h heightmap.cpp gcode_parser.h gcode_parser.cpp gcode_commands.h gcode_commands.cpp sender_app.h sender_app.cpp)
 
 add_executable(sender main.cpp ${TESTS} ${TERJE} ${SENDER_GRBL_SRC})
 target_link_libraries(sender nanogui GL gtest gtest_main)
\ No newline at end of file
diff --git a/main.cpp b/main.cpp
index 9b0a933..425afce 100644
--- a/main.cpp
+++ b/main.cpp
@@ -1,1114 +1,7 @@
-#include <nanogui/opengl.h>
-#include <nanogui/screen.h>
-#include <nanogui/window.h>
-#include <nanogui/layout.h>
-#include <nanogui/label.h>
-#include <nanogui/button.h>
-#include <nanogui/popupbutton.h>
-#include <nanogui/progressbar.h>
-#include <nanogui/messagedialog.h>
-#include <nanogui/texture.h>
-#include <nanogui/textarea.h>
-#include <nanogui/textbox.h>
-#include <nanogui/tabwidget.h>
-#include <nanogui/shader.h>
-#include <nanogui/renderpass.h>
-#include <iostream>
-#include <memory>
-
-#define STB_IMAGE_STATIC
-#define STB_IMAGE_IMPLEMENTATION
-#if defined(_MSC_VER)
-#  pragma warning (disable: 4505) // don't warn about dead code in stb_image.h
-#elif defined(__GNUC__)
-#   pragma GCC diagnostic ignored "-Wunused-function"
-#endif
-
-#include <stb_image.h>
-#include "grbl.h"
-#include <gtest/gtest.h>
-#include <regex>
-#include "grbl_machine.h"
-#include "string_utils.h"
-#include "render.h"
-#include "glm/gtx/quaternion.hpp"
-#include "nanogui/nanogui.h"
-#include "glm/gtc/matrix_inverse.hpp"
-#include "heightmap.h"
-#include <glm/ext/quaternion_float.hpp>
-#include <glm/ext/quaternion_trigonometric.hpp>
-#include <glm/vec3.hpp> // glm::vec3
-#include <glm/vec4.hpp> // glm::vec4
-#include <glm/mat4x4.hpp> // glm::mat4
-#include <glm/ext/matrix_transform.hpp> // glm::translate, glm::rotate, glm::scale
-#include <glm/ext/matrix_clip_space.hpp> // glm::perspective
-#include <glm/ext/scalar_constants.hpp> // glm::pi
-#include <fstream>
-
-using namespace nanogui;
-
-grbl::machine cnc{};
-
-class SenderApp : public Screen {
-public:
-
-    Window *window;
-    grbl::jog_state jog;
-    TextBox *txt_status;
-    TextBox *txt_message;
-    nanogui::Color color_red = nanogui::Color(255, 0, 0, 255);
-    nanogui::Color color_green = nanogui::Color(0, 255, 0, 255);
-    int last_alarm = 0;
-    grbl::program pgm;
-    Button *btn_load_program, *btn_check_program, *btn_run_program;
-
-    std::vector<std::string> jog_distances = {"0.01", "0.1", "1", "10"};
-    std::vector<std::string> jog_feed_rates = {"5", "100", "500", "1000"};
-
-    grbl::program_renderer renderer;
-
-    glm::vec3 cam_target = glm::vec3(0);
-    glm::vec3 cam_pan = glm::vec3(0);
-    float cam_zoom = 0;
-    glm::quat cam_src_rotation = glm::quat(1.0, 0.0, 0.0, 0.0); // identity quaternion
-
-    Widget *info_layer, *heightmap_layer;
-    TabWidget *tab_widget;
-    VScrollPanel *settings_vscroll;
-    Widget *settings_layer;
-
-    VScrollPanel *parameters_vscroll;
-    Widget *parameters_layer;
-    TextBox *mpos_x_text, *mpos_y_text, *mpos_z_text;
-    ComboBox *cbo_work_offset, *cbo_tool, *cbo_jog_feed_rates, *cbo_jog_distance;
-
-    ToolButton *btn_pin_door, *btn_pin_hold, *btn_pin_reset, *btn_pin_cycle_start;
-    ToolButton *btn_pin_limit_x, *btn_pin_limit_y, *btn_pin_limit_z, *btn_pin_probe;
-
-    Button *btn_keyboard_jog;
-    std::stringstream dro_ss;
-    grbl::heightmap heightmap_grid;
-
-
-    SenderApp() : Screen(Vector2i(1024, 768), "GRBL Sender") {
-        inc_ref();
-
-        window = new Window(this, "Machine status");
-        window->set_position(Vector2i(0, 0));
-        window->set_layout(new BoxLayout(nanogui::Orientation::Vertical));
-
-        tab_widget = window->add<TabWidget>();
-        tab_widget->set_tabs_draggable(true);
-        tab_widget->set_callback([&](int index) {
-            tab_widget->set_selected_index(index);
-        });
-
-        info_layer = tab_widget->add<Widget>();
-        info_layer->set_layout(new GroupLayout(10, 20, 30, 0));
-        info_layer->add<Label>("");
-
-        tab_widget->append_tab("Info", info_layer);
-
-        auto probe_layer = tab_widget->add<Widget>();
-        probe_layer->set_layout(new GroupLayout(10, 20, 30, 0));
-        probe_layer->add<Label>("");
-
-        add_status_markup();
-        add_dro_markup();
-        add_program_extents();
-        add_pins_markup();
-        add_jogging_markup();
-        add_work_parameters_markup();
-        add_z_probe_markup();
-
-        heightmap_layer = tab_widget->add<Widget>();
-        heightmap_layer->set_layout(new GroupLayout(10, 20, 30, 0));
-        heightmap_layer->add<Label>("");
-        tab_widget->append_tab("Heightmap", heightmap_layer);
-        add_heightmap_markup();
-
-
-        perform_layout();
-
-        m_render_pass = new RenderPass({this}, nullptr, nullptr, nullptr, true);
-        m_render_pass->set_clear_color(0, Color(0.13f, 0.13f, 0.13f, 1.f));
-        m_render_pass->set_depth_test(RenderPass::DepthTest::Greater, true);
-        m_render_pass->set_cull_mode(RenderPass::CullMode::Disabled);
-    }
-
-    TextBox *txt_min_z, *txt_feed;
-
-    void add_z_probe_markup() {
-        info_layer->add<Label>("Z-Probe", "sans-bold", 20);
-        auto z_probe_holder = info_layer->add<Widget>();
-        z_probe_holder->set_layout(new BoxLayout(Orientation::Vertical, Alignment::Fill, 2, 2));
-
-        auto another_holder = z_probe_holder->add<Widget>();
-        another_holder->set_layout(new GridLayout(Orientation::Horizontal, 2, Alignment::Fill, 2, 2));
-
-        another_holder->add<Label>("Feed", "sans-bold");
-        txt_feed = another_holder->add<TextBox>("100");
-        txt_feed->set_editable(true);
-        txt_feed->set_fixed_width(100);
-
-        another_holder->add<Label>("Min Z", "sans-bold");
-        txt_min_z = another_holder->add<TextBox>("-65");
-        txt_min_z->set_editable(true);
-        txt_min_z->set_fixed_width(100);
-
-        z_probe_holder->add<Label>("");
-        auto btn_start_probing = z_probe_holder->add<Button>("Start probing");
-        btn_start_probing->set_callback([&]() {
-            cnc.start_z_probe(std::stof(txt_min_z->value()), std::stof(txt_feed->value()));
-        });
-    }
-
-    void add_work_parameters_markup() {
-        // work parameters
-        info_layer->add<Label>("Work parameters", "sans-bold", 20);
-        auto work_holder = info_layer->add<Widget>();
-        work_holder->set_layout(new BoxLayout(Orientation::Horizontal, Alignment::Fill, 6, 6));
-
-        auto work_data_holder = work_holder->add<Widget>();
-        work_data_holder->set_layout(new GridLayout(Orientation::Horizontal, 2, Alignment::Fill, 6, 6));
-
-        work_data_holder->add<Label>("Offset", "sans-bold");
-        std::vector<std::string> offset_items = {"G54", "G55", "G56", "G57", "G58", "G59"};
-        cbo_work_offset = work_data_holder->add<ComboBox>(offset_items);
-        cbo_work_offset->set_callback([&](int idx) {
-            refresh_offset();
-            update_dro();
-        });
-
-        work_data_holder->add<Label>("Tool", "sans-bold");
-        std::vector<std::string> tool_items = {"None"};
-        cbo_tool = work_data_holder->add<ComboBox>(tool_items);
-
-        auto work_btn_holder = work_holder->add<Widget>();
-        work_btn_holder->set_layout(new GridLayout(Orientation::Horizontal, 3, Alignment::Fill, 0, 6));
-
-
-        btn_load_program = work_btn_holder->add<Button>("Load");
-        btn_load_program->set_callback([&] {
-            auto path = file_dialog(
-                    {{"gcode", "G-Code files"},
-                     {"nc",    "G-Code files"},
-                     {"ngc",   "G-Code files"}}, true);
-
-            if (pgm.load_from_file(path)) {
-                init_program_geometry();
-                set_program_extents();
-                fill_heightmap_from_model();
-                update_grid();
-            } else {
-            }
-        });
-        btn_load_program->set_tooltip("Load program");
-
-        btn_check_program = work_btn_holder->add<Button>("Check");
-//        btnCheckProgram->set_enabled(false);
-        btn_check_program->set_callback([&] {
-            cnc.check_program(pgm);
-        });
-        btn_check_program->set_tooltip("Check program");
-
-        btn_run_program = work_btn_holder->add<Button>("Run");
-//        btnRunProgram->set_enabled(false);
-        btn_run_program->set_callback([&] {
-            cnc.run_program(pgm, "G" + std::to_string(cbo_work_offset->selected_index() + 54));
-        });
-        btn_run_program->set_tooltip("Execute program");
-    }
-
-    void add_status_markup() {
-        auto status_holder = info_layer->add<Widget>();
-        status_holder->set_layout(new BoxLayout(Orientation::Vertical, Alignment::Fill, 0, 0));
-
-        auto status_text_holder = status_holder->add<Widget>();
-        status_text_holder->set_layout(new GridLayout(Orientation::Horizontal, 3, Alignment::Fill, 0, 0));
-
-        status_text_holder->add<Label>("Status", "sans-bold", 20);
-
-        txt_status = status_text_holder->add<TextBox>();
-        txt_status->set_editable(false);
-        txt_status->set_fixed_width(300);
-
-        auto *btn_reset = status_text_holder->add<Button>("Reset");
-        btn_reset->set_background_color(color_red);
-        btn_reset->set_callback([&] {
-            cnc.request_reset();
-        });
-
-        //
-        status_text_holder->add<Label>("");
-
-        txt_message = status_text_holder->add<TextBox>("");
-        txt_message->set_fixed_width(300);
-
-        status_text_holder->add<Label>("");
-
-        // buttons
-        auto status_btn_holder = status_holder->add<Widget>();
-        status_btn_holder->set_layout(new GridLayout(Orientation::Horizontal, 2, Alignment::Fill, 6, 6));
-
-        auto *btn_homing = new Button(status_btn_holder, "Homing", FA_HOME);
-        btn_homing->set_callback([&] {
-            cnc.request_home();
-        });
-
-        auto *btn_unlock = new Button(status_btn_holder, "Unlock", FA_UNLOCK);
-        btn_unlock->set_callback([&] {
-            cnc.request_unlock();
-        });
-
-        // buttons to change state
-        auto *btn_cycle_start = status_btn_holder->add<Button>("Cycle Start", FA_PLAY);
-        btn_cycle_start->set_callback([&] {
-            cnc.request_cycle_start();
-        });
-        auto *btn_feed_hold = status_btn_holder->add<Button>("Feed Hold", FA_PAUSE);
-        btn_feed_hold->set_callback([&] {
-            cnc.request_feed_hold();
-        });
-    }
-
-    void add_jogging_markup() {
-        // jogging
-        info_layer->add<Label>("Jogging", "sans-bold", 20);
-        auto holder = new Widget(info_layer);
-
-        holder->set_layout(new GridLayout(Orientation::Horizontal, 3, Alignment::Fill, 0, 0));
-
-        // feed and distance
-        auto jog_params_holder = holder->add<Widget>();
-        jog_params_holder->set_layout(new GridLayout(Orientation::Horizontal, 3, Alignment::Fill, 0, 4));
-
-        jog_params_holder->add<Label>("Feed", "sans-bold");
-        cbo_jog_feed_rates = jog_params_holder->add<ComboBox>(jog_feed_rates);
-        cbo_jog_feed_rates->set_selected_index(2);
-        jog_params_holder->add<Label>("mm/min");
-
-        jog_params_holder->add<Label>("Distance", "sans-bold");
-        cbo_jog_distance = jog_params_holder->add<ComboBox>(jog_distances);
-        cbo_jog_distance->set_selected_index(2);
-        jog_params_holder->add<Label>("mm");
-
-        jog_params_holder->add<Label>("Keyboard Jog", "sans-bold");
-        btn_keyboard_jog = jog_params_holder->add<Button>("", FA_KEYBOARD);
-        btn_keyboard_jog->set_flags(Button::ToggleButton);
-        jog_params_holder->add<Label>("");
-
-        // X and Y
-        auto jog_btn_holder = holder->add<Widget>();
-        jog_btn_holder->set_layout(new GridLayout(Orientation::Horizontal, 3, Alignment::Fill, 0, 6));
-
-        jog_btn_holder->add<Label>("");
-        auto jog_btn = jog_btn_holder->add<Button>("", FA_ARROW_ALT_CIRCLE_UP);
-        jog_btn->set_callback([&]() {
-            // FIXME: get rid of std::stof
-            cnc.request_jog_fixed(grbl::jog_direction::y_up,
-                                  std::stof(jog_distances[cbo_jog_distance->selected_index()]),
-                                  std::stof(jog_feed_rates[cbo_jog_feed_rates->selected_index()]));
-        });
-        jog_btn_holder->add<Label>("");
-
-        jog_btn = jog_btn_holder->add<Button>("", FA_ARROW_ALT_CIRCLE_LEFT);
-        jog_btn->set_callback([&]() {
-            // FIXME: get rid of std::stof
-            cnc.request_jog_fixed(grbl::jog_direction::x_down,
-                                  std::stof(jog_distances[cbo_jog_distance->selected_index()]),
-                                  std::stof(jog_feed_rates[cbo_jog_feed_rates->selected_index()]));
-        });
-
-        jog_btn = jog_btn_holder->add<Button>("", FA_HOME);
-        jog_btn->set_callback([&]() {
-            cnc.go_to_zero(true, true, false);
-        });
-
-
-        jog_btn = jog_btn_holder->add<Button>("", FA_ARROW_ALT_CIRCLE_RIGHT);
-        jog_btn->set_callback([&]() {
-            // FIXME: get rid of std::stof
-            cnc.request_jog_fixed(grbl::jog_direction::x_up,
-                                  std::stof(jog_distances[cbo_jog_distance->selected_index()]),
-                                  std::stof(jog_feed_rates[cbo_jog_feed_rates->selected_index()]));
-        });
-
-        jog_btn_holder->add<Label>("");
-        jog_btn = jog_btn_holder->add<Button>("", FA_ARROW_ALT_CIRCLE_DOWN);
-        jog_btn->set_callback([&]() {
-            // FIXME: get rid of std::stof
-            cnc.request_jog_fixed(grbl::jog_direction::y_down,
-                                  std::stof(jog_distances[cbo_jog_distance->selected_index()]),
-                                  std::stof(jog_feed_rates[cbo_jog_feed_rates->selected_index()]));
-        });
-        jog_btn_holder->add<Label>("");
-
-
-        // z up/down
-        auto jog_z_btn_holder = holder->add<Widget>();
-        jog_z_btn_holder->set_layout(new BoxLayout(Orientation::Vertical, Alignment::Fill, 0, 6));
-
-        jog_btn = jog_z_btn_holder->add<Button>("", FA_CHEVRON_UP);
-        jog_btn->set_callback([&]() {
-            // FIXME: get rid of std::stof
-            cnc.request_jog_fixed(grbl::jog_direction::z_up,
-                                  std::stof(jog_distances[cbo_jog_distance->selected_index()]),
-                                  std::stof(jog_feed_rates[cbo_jog_feed_rates->selected_index()]));
-        });
-
-        jog_btn = jog_z_btn_holder->add<Button>("", FA_HOME);
-        jog_btn->set_callback([&]() {
-            cnc.go_to_zero(false, false, true);
-        });
-
-        jog_btn = jog_z_btn_holder->add<Button>("", FA_CHEVRON_DOWN);
-        jog_btn->set_callback([&]() {
-            // FIXME: get rid of std::stof
-            cnc.request_jog_fixed(grbl::jog_direction::z_down,
-                                  std::stof(jog_distances[cbo_jog_distance->selected_index()]),
-                                  std::stof(jog_feed_rates[cbo_jog_feed_rates->selected_index()]));
-        });
-    }
-
-    void add_dro_markup() {
-        dro_ss << std::setprecision(3) << std::fixed;
-
-        // DRO
-        info_layer->add<Label>("DRO", "sans-bold", 20);
-        auto dro_holder = info_layer->add<Widget>();
-        dro_holder->set_layout(new GridLayout(Orientation::Horizontal, 1, Alignment::Middle, 0, 6));
-
-        auto x_holder = dro_holder->add<Widget>();
-        x_holder->set_layout(new BoxLayout(Orientation::Horizontal, Alignment::Middle, 0, 6));
-        auto lbl = x_holder->add<Label>("X", "sans-bold", 20);
-        lbl->set_fixed_width(30);
-        mpos_x_text = x_holder->add<TextBox>(std::to_string(cnc.get_status().machine_pos[0]));
-        mpos_x_text->set_fixed_width(200);
-        auto zero_btn = x_holder->add<ToolButton>(FA_BAN);
-        zero_btn->set_flags(Button::NormalButton);
-        zero_btn->set_tooltip("Zero axis");
-        zero_btn->set_callback([&]() {
-            cnc.zero_offset_axis(cbo_work_offset->selected_index(), 0);
-        });
-
-        auto y_holder = dro_holder->add<Widget>();
-        y_holder->set_layout(new BoxLayout(Orientation::Horizontal, Alignment::Middle, 0, 6));
-        lbl = y_holder->add<Label>("Y", "sans-bold", 20);
-        lbl->set_fixed_width(30);
-        mpos_y_text = y_holder->add<TextBox>(std::to_string(cnc.get_status().machine_pos[1]));
-        mpos_y_text->set_fixed_width(200);
-        zero_btn = y_holder->add<ToolButton>(FA_BAN);
-        zero_btn->set_flags(Button::NormalButton);
-        zero_btn->set_tooltip("Zero axis");
-        zero_btn->set_callback([&]() {
-            cnc.zero_offset_axis(cbo_work_offset->selected_index(), 1);
-        });
-
-        auto z_holder = dro_holder->add<Widget>();
-        z_holder->set_layout(new BoxLayout(Orientation::Horizontal, Alignment::Middle, 0, 6));
-        lbl = z_holder->add<Label>("Z", "sans-bold", 20);
-        lbl->set_fixed_width(30);
-        mpos_z_text = z_holder->add<TextBox>(std::to_string(cnc.get_status().machine_pos[0]));
-        mpos_z_text->set_fixed_width(200);
-        zero_btn = z_holder->add<ToolButton>(FA_BAN);
-        zero_btn->set_flags(Button::NormalButton);
-        zero_btn->set_tooltip("Zero axis");
-        zero_btn->set_callback([&]() {
-            cnc.zero_offset_axis(cbo_work_offset->selected_index(), 2);
-        });
-
-        auto axis_btn_holder = dro_holder->add<Widget>();
-        axis_btn_holder->set_layout(new BoxLayout(Orientation::Horizontal, Alignment::Middle, 0, 6));
-
-        auto zero_all_btn = axis_btn_holder->add<Button>("Zero all");
-        zero_all_btn->set_callback([&]() {
-            cnc.zero_offset(cbo_work_offset->selected_index());
-        });
-
-        auto goto_zero_btn = axis_btn_holder->add<Button>("Goto 0");
-        goto_zero_btn->set_callback([&]() {
-            cnc.go_to_zero(true, true, true);
-        });
-    }
-
-    TextBox *extents_min_x, *extents_max_x;
-    TextBox *extents_min_y, *extents_max_y;
-    TextBox *extents_min_z, *extents_max_z;
-
-    void add_program_extents() {
-        dro_ss << std::setprecision(3) << std::fixed;
-
-        // Program extents
-        info_layer->add<Label>("Program extents", "sans-bold", 20);
-        auto extents_holder = info_layer->add<Widget>();
-        extents_holder->set_layout(new GridLayout(Orientation::Horizontal, 3, Alignment::Fill, 4, 4));
-
-        extents_holder->add<Label>("X", "sans-bold", 20);
-        extents_min_x = extents_holder->add<TextBox>("");
-        extents_max_x = extents_holder->add<TextBox>("");
-
-        extents_holder->add<Label>("Y", "sans-bold", 20);
-        extents_min_y = extents_holder->add<TextBox>("");
-        extents_max_y = extents_holder->add<TextBox>("");
-
-        extents_holder->add<Label>("Z", "sans-bold", 20);
-        extents_min_z = extents_holder->add<TextBox>("");
-        extents_max_z = extents_holder->add<TextBox>("");
-    }
-
-    TextBox *txt_heightmap_from_x, *txt_heightmap_from_y;
-    TextBox *txt_heightmap_to_x, *txt_heightmap_to_y;
-    TextBox *txt_heightmap_res;
-    TextBox *txt_clearance_height, *txt_start_probing_at, *txt_max_negative_z, *txt_final_z_height;
-
-    static void save_heightmap(const grbl::heightmap& grid, std::string path) {
-        std::ofstream out(path);
-        if (out) {
-            out << "from_x:" << grid.from_x << std::endl;
-            out << "from_y:" << grid.from_y << std::endl;
-            out << "to_x:" << grid.to_x << std::endl;
-            out << "to_y:" << grid.to_y << std::endl;
-            out << "resolution:" << grid.resolution << std::endl;
-            out << "probes:" << grid.vertices.size() << std::endl;
-            for (auto& v: grid.vertices) {
-                out << v.x << ":" << v.y << ":" << v.z << std::endl;
-            }
-        }
-    }
-
-    grbl::heightmap load_heightmap(std::string path) {
-        grbl::heightmap result{};
-
-        std::ifstream in_file(path);
-        if (in_file) {
-            float from_x, from_y;
-            float to_x, to_y;
-            float resolution;
-            size_t probe_location = 0;
-
-            for (std::string line; std::getline(in_file, line);) {
-                auto pieces = split_string(line, ":");
-                if (pieces[0] == "from_x") {
-                    from_x = std::stof(pieces[1]);
-                } else if (pieces[0] == "from_y") {
-                    from_y = std::stof(pieces[1]);
-                } else if (pieces[0] == "to_x") {
-                    to_x = std::stof(pieces[1]);
-                } else if (pieces[0] == "to_y") {
-                    to_y = std::stof(pieces[1]);
-                } else if (pieces[0] == "resolution") {
-                    resolution = std::stof(pieces[1]);
-                } else if (pieces[0] == "probes") {
-                    result = grbl::heightmap::from_params(from_x, from_y, to_x, to_y, resolution);
-                } else {
-                    result.vertices[probe_location].x = std::stof(pieces[0]);
-                    result.vertices[probe_location].y = std::stof(pieces[1]);
-                    result.vertices[probe_location].z = std::stof(pieces[2]);
-                    probe_location++;
-                }
-            }
-        }
-
-        return result;
-    }
-
-    void fill_heightmap_controls_from_grid(const grbl::heightmap& grid) const {
-        txt_heightmap_from_x->set_value(std::to_string(grid.from_x));
-        txt_heightmap_from_y->set_value(std::to_string(grid.from_y));
-        txt_heightmap_to_x->set_value(std::to_string(grid.to_x));
-        txt_heightmap_to_y->set_value(std::to_string(grid.to_y));
-        txt_heightmap_res->set_value(std::to_string(grid.resolution));
-    }
-
-    void add_heightmap_markup() {
-        heightmap_layer->add<Label>("Grid definition", "sans-bold", 20);
-        auto heightmap_params_holder = heightmap_layer->add<Widget>();
-        heightmap_params_holder->set_layout(new BoxLayout(Orientation::Vertical, Alignment::Fill, 4, 4));
-
-        // grid size
-        auto grid_size_holder = heightmap_params_holder->add<Widget>();
-        grid_size_holder->set_layout(new GridLayout(Orientation::Horizontal, 3, Alignment::Middle, 4, 4));
-
-        grid_size_holder->add<Label>("", "sans-bold", 20);
-        grid_size_holder->add<Label>("X", "sans-bold", 20);
-        grid_size_holder->add<Label>("Y", "sans-bold", 20);
-
-        grid_size_holder->add<Label>("From", "sans-bold", 20);
-        txt_heightmap_from_x = grid_size_holder->add<TextBox>("");
-        txt_heightmap_from_x->set_editable(true);
-        txt_heightmap_from_x->set_fixed_width(150);
-        txt_heightmap_from_y = grid_size_holder->add<TextBox>("");
-        txt_heightmap_from_y->set_editable(true);
-        txt_heightmap_from_y->set_fixed_width(150);
-
-        grid_size_holder->add<Label>("To", "sans-bold", 20);
-        txt_heightmap_to_x = grid_size_holder->add<TextBox>("");
-        txt_heightmap_to_x->set_editable(true);
-        txt_heightmap_to_x->set_fixed_width(150);
-        txt_heightmap_to_y = grid_size_holder->add<TextBox>("");
-        txt_heightmap_to_y->set_editable(true);
-        txt_heightmap_to_y->set_fixed_width(150);
-
-        grid_size_holder->add<Label>("");
-        auto btn = grid_size_holder->add<Button>("Fetch from model");
-        btn->set_callback([&]() {
-            fill_heightmap_from_model();
-        });
-        auto btn_load_heightmap = grid_size_holder->add<Button>("Load from file");
-        btn_load_heightmap->set_callback([&]() {
-            auto path = file_dialog(
-                    {{"hmap", "Heightmap files"}
-                    }, true);
-            if (!path.empty()) {
-                heightmap_grid = load_heightmap(path);
-                fill_heightmap_controls_from_grid(heightmap_grid);
-                renderer.update_grid(heightmap_grid);
-            }
-        });
-
-        txt_heightmap_from_x->set_callback([&](const std::string& new_value) {
-            update_grid();
-            return true;
-        });
-        txt_heightmap_from_y->set_callback([&](const std::string& new_value) {
-            update_grid();
-            return true;
-        });
-
-        txt_heightmap_to_x->set_callback([&](const std::string& new_value) {
-            update_grid();
-            return true;
-        });
-        txt_heightmap_to_y->set_callback([&](const std::string& new_value) {
-            update_grid();
-            return true;
-        });
-
-
-        // grid resolution
-        auto grid_res_holder = heightmap_params_holder->add<Widget>();
-        grid_res_holder->set_layout(new BoxLayout(nanogui::Orientation::Horizontal, Alignment::Middle, 4, 4));
-        grid_res_holder->add<Label>("Grid resolution", "sans-bold", 20);
-        txt_heightmap_res = grid_res_holder->add<TextBox>("5");
-        txt_heightmap_res->set_editable(true);
-        txt_heightmap_res->set_fixed_width(150);
-        txt_heightmap_res->set_callback([&](const std::string& new_value) {
-            update_grid();
-            return true;
-        });
-        grid_res_holder->add<Label>("mm", "sans-bold", 20);
-
-        // business params
-        auto heightmap_business_holder = heightmap_params_holder->add<Widget>();
-        heightmap_business_holder->set_layout(new GridLayout(nanogui::Orientation::Horizontal, 3, Alignment::Fill, 4, 4));
-
-        heightmap_business_holder->add<Label>("Clearance height Z", "sans-bold", 20);
-        txt_clearance_height = heightmap_business_holder->add<TextBox>("1.5");
-        txt_clearance_height->set_editable(true);
-        heightmap_business_holder->add<Label>("", "sans-bold");
-
-        heightmap_business_holder->add<Label>("Start probing at Z", "sans-bold", 20);
-        txt_start_probing_at = heightmap_business_holder->add<TextBox>("0.5");
-        txt_start_probing_at->set_editable(true);
-        heightmap_business_holder->add<Label>("", "sans-bold");
-
-        heightmap_business_holder->add<Label>("Max negative Z", "sans-bold", 20);
-        txt_max_negative_z = heightmap_business_holder->add<TextBox>("-1.0");
-        txt_max_negative_z->set_editable(true);
-        heightmap_business_holder->add<Label>("(when to fail probing)", "sans-bold");
-
-        heightmap_business_holder->add<Label>("Final Z safety height", "sans-bold", 20);
-        txt_final_z_height = heightmap_business_holder->add<TextBox>("15");
-        txt_final_z_height->set_editable(true);
-        heightmap_business_holder->add<Label>("", "sans-bold");
-
-        heightmap_business_holder->add<Label>("", "sans-bold");
-        auto btn_start_probing = heightmap_business_holder->add<Button>("Start Probing");
-        btn_start_probing->set_callback([&]() {
-            cnc.probe_heightmap(heightmap_grid);
-        });
-        auto btn_save_heightmap = heightmap_business_holder->add<Button>("Save heightmap");
-        btn_save_heightmap->set_callback([&]() {
-            auto path = file_dialog(
-                    {{"hmap", "Heightmap files"}
-                    }, true);
-            if (!path.empty()) {
-                save_heightmap(heightmap_grid, path);
-            }
-        });
-    }
-
-    void fill_heightmap_from_model() const {
-        auto min = renderer.get_extents_min();
-        auto max = renderer.get_extents_max();
-        txt_heightmap_from_x->set_value(std::to_string(min.x));
-        txt_heightmap_from_y->set_value(std::to_string(min.y));
-        txt_heightmap_to_x->set_value(std::to_string(max.x));
-        txt_heightmap_to_y->set_value(std::to_string(max.y));
-    }
-
-    void update_grid() {
-        auto from_x = std::stof(txt_heightmap_from_x->value());
-        auto from_y = std::stof(txt_heightmap_from_y->value());
-        auto to_x = std::stof(txt_heightmap_to_x->value());
-        auto to_y = std::stof(txt_heightmap_to_y->value());
-        auto res = std::stof(txt_heightmap_res->value());
-
-        if (from_x != heightmap_grid.from_x ||
-            from_y != heightmap_grid.from_y ||
-            to_x != heightmap_grid.to_x ||
-            to_y != heightmap_grid.to_y ||
-            res != heightmap_grid.resolution) {
-            heightmap_grid = std::move(grbl::heightmap::from_params(from_x, from_y, to_x, to_y, res));
-            renderer.update_grid(heightmap_grid);
-        }
-
-    }
-
-    void add_pins_markup() {
-        // Pins
-        info_layer->add<Label>("Pins", "sans-bold", 20);
-        auto pins_holder = info_layer->add<Widget>();
-        pins_holder->set_layout(new BoxLayout(Orientation::Horizontal, Alignment::Fill, 4, 4));
-
-        btn_pin_door = pins_holder->add<ToolButton>(0, "D");
-//        btn_pin_door->set_enabled(false);
-        btn_pin_door->set_flags(Button::Flags::NormalButton);
-
-        btn_pin_hold = pins_holder->add<ToolButton>(0, "H");
-//        btn_pin_hold->set_enabled(false);
-        btn_pin_hold->set_flags(Button::Flags::NormalButton);
-
-        btn_pin_reset = pins_holder->add<ToolButton>(0, "R");
-//        btn_pin_reset->set_enabled(false);
-        btn_pin_reset->set_flags(Button::Flags::NormalButton);
-
-        btn_pin_cycle_start = pins_holder->add<ToolButton>(0, "S");
-//        btn_pin_cycle_start->set_enabled(false);
-        btn_pin_cycle_start->set_flags(Button::Flags::NormalButton);
-
-        auto a = pins_holder->add<Label>("");
-        a->set_fixed_width(30);
-
-        btn_pin_limit_x = pins_holder->add<ToolButton>(0, "X");
-//        btn_pin_limit_x->set_enabled(false);
-        btn_pin_limit_x->set_flags(Button::Flags::NormalButton);
-
-        btn_pin_limit_y = pins_holder->add<ToolButton>(0, "Y");
-//        btn_pin_limit_y->set_enabled(false);
-        btn_pin_limit_y->set_flags(Button::Flags::NormalButton);
-
-        btn_pin_limit_z = pins_holder->add<ToolButton>(0, "Z");
-//        btn_pin_limit_z->set_enabled(false);
-        btn_pin_limit_z->set_flags(Button::Flags::NormalButton);
-
-        btn_pin_probe = pins_holder->add<ToolButton>(0, "P");
-//        btn_pin_probe->set_enabled(false);
-        btn_pin_probe->set_flags(Button::Flags::NormalButton);
-    }
-
-    void refresh_offset() const {
-        auto offset_name = "G" + std::to_string(cbo_work_offset->selected_index() + 54);
-        cnc.set_work_offset(offset_name);
-    }
-
-    void fill_in_parameters() {
-        parameters_vscroll = new VScrollPanel(tab_widget);
-        tab_widget->append_tab("Parameters", parameters_vscroll);
-
-        parameters_layer = new Widget(parameters_vscroll);
-        parameters_layer->set_layout(new GridLayout(Orientation::Horizontal, 1, Alignment::Middle));
-
-        auto& parameters = cnc.get_parameters();
-
-        for (auto& entry: parameters) {
-            auto w = parameters_layer->add<Widget>();
-            w->set_layout(new BoxLayout(Orientation::Horizontal, Alignment::Middle, 2, 2));
-            auto x = w->add<Label>(entry.first, "sans-bold", 20);
-            x->set_fixed_width(50);
-
-            auto y = w->add<TextBox>(entry.second);
-            y->set_editable(true);
-            y->set_fixed_width(200);
-
-            auto z = w->add<Button>("", FA_SAVE);
-//            z->set_flags(Button::Flags::NormalButton); // no toggle, please
-            z->set_tooltip("save");
-        }
-    }
-
-
-    void fill_in_settings() {
-        settings_vscroll = new VScrollPanel(tab_widget);
-        tab_widget->append_tab("Settings", settings_vscroll);
-
-        settings_layer = new Widget(settings_vscroll);
-        settings_layer->set_layout(new GridLayout(Orientation::Horizontal, 1, Alignment::Middle));
-
-        auto& settings = cnc.get_settings();
-
-        for (auto& s: settings) {
-            auto w = settings_layer->add<Widget>();
-            w->set_layout(new BoxLayout(Orientation::Horizontal, Alignment::Middle, 2, 2));
-            auto x = w->add<Label>(s.first, "sans-bold", 20);
-            x->set_fixed_width(40);
-
-            auto desc = grbl::setting_description(std::stoi(s.first.substr(1)));
-
-            auto y = w->add<TextBox>(s.second);
-            y->set_editable(true);
-            y->set_tooltip(desc);
-            y->set_fixed_width(150);
-
-            auto z = w->add<ToolButton>(FA_SAVE);
-            z->set_flags(Button::Flags::NormalButton); // no toggle, please
-            z->set_tooltip("save");
-
-            auto t = w->add<TextArea>();
-            t->set_fixed_width(200);
-            t->set_fixed_height(20);
-            t->clear();
-            t->append(desc.substr(0, desc.find_first_of('\n')));
-        }
-    }
-
-    void init_program_geometry() {
-        renderer.update(pgm, cnc);
-
-        auto max_pos = renderer.get_extents_max();
-        auto min_pos = renderer.get_extents_min();
-
-        cam_target = (max_pos - min_pos) / 2.0f;
-        cam_zoom = (max_pos.x - min_pos.x);
-        cam_src_rotation = glm::quat(1.0, 0.0, 0.0, 0.0);
-    }
-
-    void set_program_extents() {
-        auto min = renderer.get_extents_min();
-        auto max = renderer.get_extents_max();
-
-        extents_min_x->set_value(std::to_string(min.x));
-        extents_max_x->set_value(std::to_string(max.x));
-
-        extents_min_y->set_value(std::to_string(min.y));
-        extents_max_y->set_value(std::to_string(max.y));
-
-        extents_min_z->set_value(std::to_string(min.z));
-        extents_max_z->set_value(std::to_string(max.z));
-    }
-
-    bool resize_event(const Vector2i& size) override {
-//        window->set_fixed_height(this->height() / 2);
-        tab_widget->set_fixed_height((this->height() - 30));
-        perform_layout();
-
-        return Screen::resize_event(size);
-    }
-
-    grbl::realtime_status_report last_report;
-
-    void update_dro() {
-        auto work_pos = cnc.get_work_pos();
-
-        dro_ss.str("");
-        dro_ss << work_pos[0];
-        mpos_x_text->set_value(dro_ss.str());
-
-        dro_ss.str("");
-        dro_ss << work_pos[1];
-        mpos_y_text->set_value(dro_ss.str());
-
-        dro_ss.str("");
-        dro_ss << work_pos[2];
-        mpos_z_text->set_value(dro_ss.str());
-    }
-
-
-    bool keyboard_event(int key, int scancode, int action, int modifiers) override {
-        if (Screen::keyboard_event(key, scancode, action, modifiers))
-            return true;
-
-//        if (key == GLFW_KEY_ESCAPE && action == GLFW_PRESS) {
-//            set_visible(false);
-//            return true;
-//        }
-
-        if (key == GLFW_KEY_SPACE && action == GLFW_PRESS && !window->mouse_focused()) {
-            // reset trackball rotation
-            cam_src_rotation = glm::quat(1, 0, 0, 0);
-        }
-
-        auto new_jog = jog;
-
-        if (key == GLFW_KEY_LEFT_SHIFT) {
-            if (action == GLFW_PRESS) {
-                new_jog.speed_fast_pressed = true;
-            } else if (action == GLFW_RELEASE) {
-                new_jog.speed_fast_pressed = false;
-            }
-        }
-
-        if (key == GLFW_KEY_LEFT_CONTROL) {
-            if (action == GLFW_PRESS) {
-                new_jog.speed_slow_pressed = true;
-            } else if (action == GLFW_RELEASE) {
-                new_jog.speed_slow_pressed = false;
-            }
-        }
-
-        if (key == GLFW_KEY_UP) {
-            if (action == GLFW_PRESS) {
-                new_jog.up_pressed = true;
-            } else if (action == GLFW_RELEASE) {
-                new_jog.up_pressed = false;
-            }
-        }
-
-        if (key == GLFW_KEY_DOWN) {
-            if (action == GLFW_PRESS) {
-                new_jog.down_pressed = true;
-            } else if (action == GLFW_RELEASE) {
-                new_jog.down_pressed = false;
-            }
-        }
-
-        if (key == GLFW_KEY_LEFT) {
-            if (action == GLFW_PRESS) {
-                new_jog.left_pressed = true;
-            } else if (action == GLFW_RELEASE) {
-                new_jog.left_pressed = false;
-            }
-        }
-
-        if (key == GLFW_KEY_RIGHT) {
-            if (action == GLFW_PRESS) {
-                new_jog.right_pressed = true;
-            } else if (action == GLFW_RELEASE) {
-                new_jog.right_pressed = false;
-            }
-        }
-
-        if (key == GLFW_KEY_PAGE_UP) {
-            if (action == GLFW_PRESS) {
-                new_jog.z_up_pressed = true;
-            } else if (action == GLFW_RELEASE) {
-                new_jog.z_up_pressed = false;
-            }
-        }
-
-        if (key == GLFW_KEY_PAGE_DOWN) {
-            if (action == GLFW_PRESS) {
-                new_jog.z_down_pressed = true;
-            } else if (action == GLFW_RELEASE) {
-                new_jog.z_down_pressed = false;
-            }
-        }
-
-        if (btn_keyboard_jog->pushed() && jog != new_jog) {
-            cnc.request_jog(new_jog);
-            jog = new_jog;
-        }
-
-        return false;
-    }
-
-    bool mouse_motion_event(const Vector2i& p, const Vector2i& rel, int button, int modifiers) override {
-        auto result = Widget::mouse_motion_event(p, rel, button, modifiers);
-        if (window->mouse_focused()) {
-            return result;
-        } else {
-//            std::cout << "Mouse motion p:" << p << ", rel:" << rel << ", button:" << button << ", .modifiers:" << modifiers << std::endl;
-            bool is_rotating = button == 1;
-            bool is_panning = button == 2;
-            if (is_rotating) {
-                if (abs(rel.x()) > abs(rel.y())) {
-                    cam_src_rotation *= glm::angleAxis(rel.x() / 100.0f, glm::vec3(0, 1, 0));
-                } else {
-                    cam_src_rotation *= glm::angleAxis(rel.y() / 100.0f, glm::vec3(1, 0, 0));
-                }
-
-            } else if (is_panning) {
-                cam_pan.x += (float) rel.x() / 10.0f;
-                cam_pan.y -= (float) rel.y() / 10.0f;
-            }
-            return true;
-        }
-    }
-
-    bool scroll_event(const Vector2i& p, const Vector2f& rel) override {
-        if (window->mouse_focused()) {
-            return Widget::scroll_event(p, rel);
-        } else {
-//            std::cout << "Scroll event: p:" << p << ", rel:" << rel << std::endl;
-            cam_zoom -= rel.y() * cam_zoom / 10.0f;
-            cam_zoom = std::max(cam_zoom, 0.1f);
-
-            return true;
-        }
-    }
-
-    void draw(NVGcontext *ctx) override {
-        std::shared_ptr<grbl::machine_event> event;
-        while ((event = cnc.pop_event()) != nullptr) {
-            switch (event->type) {
-                case grbl::machine_event_type::connected:
-                    break;
-                case grbl::machine_event_type::disconnected:
-                    break;
-                case grbl::machine_event_type::report_received: {
-
-                    auto ev = dynamic_cast<grbl::machine_event_report_received *>(event.get());
-
-                    txt_status->set_value(grbl::status_to_string(cnc.get_status().status));
-
-                    if (cnc.get_status().status == grbl::machine_status::alarm) {
-                        txt_status->set_tooltip(grbl::alarm_to_string(last_alarm));
-                    } else {
-                        txt_status->set_tooltip(cnc.get_status().sub_status);
-                    }
-
-                    // FIXME: ugly way of retrieving the bg color
-                    btn_pin_door->set_background_color(ev->report.signals.bit.door ? color_red : btn_load_program->background_color());
-                    btn_pin_hold->set_background_color(ev->report.signals.bit.hold ? color_red : btn_load_program->background_color());
-                    btn_pin_reset->set_background_color(
-                            ev->report.signals.bit.soft_reset ? color_red : btn_load_program->background_color());
-                    btn_pin_cycle_start->set_background_color(
-                            ev->report.signals.bit.cycle_start ? color_red : btn_load_program->background_color());
-                    btn_pin_limit_x->set_background_color(
-                            ev->report.signals.bit.x_limit ? color_red : btn_load_program->background_color());
-                    btn_pin_limit_y->set_background_color(
-                            ev->report.signals.bit.y_limit ? color_red : btn_load_program->background_color());
-                    btn_pin_limit_z->set_background_color(
-                            ev->report.signals.bit.z_limit ? color_red : btn_load_program->background_color());
-                    btn_pin_probe->set_background_color(ev->report.signals.bit.probe ? color_red : btn_load_program->background_color());
-
-                    update_dro();
-                    last_report = ev->report;
-                    break;
-                }
-                case grbl::machine_event_type::banner:
-                    break;
-                case grbl::machine_event_type::message: {
-                    auto ev = dynamic_cast<grbl::machine_event_message *>(event.get());
-                    txt_message->set_value(ev->message);
-                    set_caption(ev->message);
-                    break;
-                }
-                case grbl::machine_event_type::alarm: {
-                    auto ev = dynamic_cast<grbl::machine_event_alarm *>(event.get());
-                    last_alarm = ev->alarm;
-                    break;
-                }
-                case grbl::machine_event_type::init_completed:
-                    fill_in_settings();
-                    fill_in_parameters();
-
-                    perform_layout();
-
-                    refresh_offset();
-                    update_dro();
-                    break;
-                case grbl::machine_event_type::run_completed: {
-                    auto ev = dynamic_cast<grbl::machine_event_run_completed *>(event.get());
-                    btn_run_program->set_background_color(ev->success ? color_green : color_red);
-                    if (ev->success) {
-                        new MessageDialog(this, MessageDialog::Type::Information, "Run result", "Program executed successfully");
-                    } else {
-                        std::stringstream ss;
-                        auto i = pgm.instruction_at(ev->failed_index);
-                        ss << "Program execution failed at line " << i.line << " (" << i.command << "). Error: "
-                           << ev->error << ", "
-                           << grbl::error_to_string(ev->error);
-                        new MessageDialog(this, MessageDialog::Type::Warning, "Run result", ss.str());
-                    }
-                    break;
-                }
-                case grbl::machine_event_type::check_completed: {
-                    auto ev = dynamic_cast<grbl::machine_event_check_completed *>(event.get());
-
-                    btn_check_program->set_background_color(ev->success ? color_green : color_red);
-                    if (ev->success) {
-                        btn_run_program->set_enabled(true);
-                        new MessageDialog(this, MessageDialog::Type::Information, "Check result", "Program checked successfully");
-                    } else {
-                        btn_run_program->set_enabled(false);
-                        std::stringstream ss;
-                        auto i = pgm.instruction_at(ev->failed_index);
-                        ss << "Program check failed at line " << i.line << " (" << i.command << "). Error: "
-                           << ev->error << ", "
-                           << grbl::error_to_string(ev->error);
-                        new MessageDialog(this, MessageDialog::Type::Warning, "Check result", ss.str());
-                    }
-                    break;
-                }
-                case grbl::machine_event_type::settings_reloaded:
-                    break;
-                case grbl::machine_event_type::parameters_reloaded:
-                    refresh_offset();
-                    update_dro();
-                    break;
-                case grbl::machine_event_type::probe_result: {
-                    auto ev = dynamic_cast<grbl::machine_event_probe_result *>(event.get());
-
-                    std::stringstream ss;
-                    ss << "Probing ended. Result: " << std::boolalpha << ev->probe_touched << " at coords: ";
-                    for (float probe_coord: ev->probe_coords) {
-                        ss << probe_coord << ", ";
-                    }
-                    new MessageDialog(this, MessageDialog::Type::Warning, "Probe result", ss.str());
-                    break;
-                }
-                case grbl::machine_event_type::heightmap_probe_acquired: {
-                    std::cout << "Updating grid" << std::endl;
-                    auto ev = dynamic_cast<grbl::machine_event_heightmap_probe_acquired *>(event.get());
-                    renderer.update_grid(*ev->grid);
-                    break;
-                }
-            }
-        }
-
-
-        Widget::draw(ctx);
-    }
-
-    void draw_contents() override {
-        auto fb_size = framebuffer_size();
-
-        // start rendering
-        m_render_pass->resize(framebuffer_size());
-        m_render_pass->begin();
-
-        renderer.update(pgm, cnc);
-        // compute mvp
-        glm::mat4 projection = glm::perspective(45.0f * glm::pi<float>() / 180.0f,
-                                                (float) fb_size.x() / (float) fb_size.y(),
-                                                0.1f,
-                                                10000.f);
-
-        glm::mat4 view = glm::translate(glm::mat4(1.0f), glm::vec3(0, 0, -cam_zoom)) *
-                         glm::toMat4(cam_src_rotation) *
-                         glm::translate(glm::mat4(1.0f), cam_pan - cam_target);
-
-        glm::mat4 model = glm::mat4(1.0f);
-        glm::mat3 normal_mat = glm::inverseTranspose(glm::mat3(view * model));
-
-        renderer.render(model, view, projection, normal_mat, glm::vec2(fb_size.x(), fb_size.y()));
-
-        m_render_pass->end();
-    }
-
-private:
-    ProgressBar *m_progress;
-    ref<RenderPass> m_render_pass;
-
-    using ImageHolder = std::unique_ptr<uint8_t[], void (*)(void *)>;
-    std::vector<std::pair<ref<Texture>, ImageHolder>> m_images;
-};
+#include "sender_app.h"
 
 
 int main(int argc, char **argv) {
-
     testing::InitGoogleTest(&argc, argv);
     auto result = RUN_ALL_TESTS();
     if (result) {
@@ -1120,18 +13,16 @@ int main(int argc, char **argv) {
 
         // scoped variables
         {
-            ref<SenderApp> app = new SenderApp();
+            nanogui::ref<SenderApp> app = new SenderApp();
             app->dec_ref();
             app->draw_all();
             app->set_visible(true);
 
-            cnc.connect();
-
             nanogui::mainloop(1 / 60.f * 1000);
         }
 
         nanogui::shutdown();
-    } catch (const std::exception& e) {
+    } catch (const std::exception &e) {
         std::string error_msg = std::string("Caught a fatal error: ") + std::string(e.what());
         std::cerr << error_msg << std::endl;
         return -1;
diff --git a/sender_app.cpp b/sender_app.cpp
new file mode 100644
index 0000000..c96bc88
--- /dev/null
+++ b/sender_app.cpp
@@ -0,0 +1,1029 @@
+#include "sender_app.h"
+
+SenderApp::SenderApp()
+        : nanogui::Screen(nanogui::Vector2i(1024, 768), "GRBL Sender") {
+    inc_ref();
+
+    window = new nanogui::Window(this, "Machine status");
+    window->set_position(nanogui::Vector2i(0, 0));
+    window->set_layout(new nanogui::BoxLayout(nanogui::Orientation::Vertical));
+
+    tab_widget = window->add<nanogui::TabWidget>();
+    tab_widget->set_tabs_draggable(true);
+    tab_widget->set_callback([&](int index) {
+        tab_widget->set_selected_index(index);
+    });
+
+    info_layer = tab_widget->add<Widget>();
+    info_layer->set_layout(new nanogui::GroupLayout(10, 20, 30, 0));
+    info_layer->add<nanogui::Label>("");
+
+    tab_widget->append_tab("Info", info_layer);
+
+    auto probe_layer = tab_widget->add<Widget>();
+    probe_layer->set_layout(new nanogui::GroupLayout(10, 20, 30, 0));
+    probe_layer->add<nanogui::Label>("");
+
+    add_status_markup();
+    add_dro_markup();
+    add_program_extents();
+    add_pins_markup();
+    add_jogging_markup();
+    add_work_parameters_markup();
+    add_z_probe_markup();
+
+    heightmap_layer = tab_widget->add<Widget>();
+    heightmap_layer->set_layout(new nanogui::GroupLayout(10, 20, 30, 0));
+    heightmap_layer->add<nanogui::Label>("");
+    tab_widget->append_tab("Heightmap", heightmap_layer);
+    add_heightmap_markup();
+
+    perform_layout();
+
+    m_render_pass = new nanogui::RenderPass({this}, nullptr, nullptr, nullptr, true);
+    m_render_pass->set_clear_color(0, nanogui::Color(0.13f, 0.13f, 0.13f, 1.f));
+    m_render_pass->set_depth_test(nanogui::RenderPass::DepthTest::Greater, true);
+    m_render_pass->set_cull_mode(nanogui::RenderPass::CullMode::Disabled);
+
+    cnc.connect();
+}
+
+void SenderApp::add_z_probe_markup() {
+    info_layer->add<nanogui::Label>("Z-Probe", "sans-bold", 20);
+    auto z_probe_holder = info_layer->add<nanogui::Widget>();
+    z_probe_holder->set_layout(
+            new nanogui::BoxLayout(nanogui::Orientation::Vertical, nanogui::Alignment::Fill, 2, 2));
+
+    auto another_holder = z_probe_holder->add<Widget>();
+    another_holder->set_layout(
+            new nanogui::GridLayout(nanogui::Orientation::Horizontal, 2, nanogui::Alignment::Fill, 2, 2));
+
+    another_holder->add<nanogui::Label>("Feed", "sans-bold");
+    txt_feed = another_holder->add<nanogui::TextBox>("100");
+    txt_feed->set_editable(true);
+    txt_feed->set_fixed_width(100);
+
+    another_holder->add<nanogui::Label>("Min Z", "sans-bold");
+    txt_min_z = another_holder->add<nanogui::TextBox>("-65");
+    txt_min_z->set_editable(true);
+    txt_min_z->set_fixed_width(100);
+
+    z_probe_holder->add<nanogui::Label>("");
+    auto btn_start_probing = z_probe_holder->add<nanogui::Button>("Start probing");
+    btn_start_probing->set_callback([&]() {
+        cnc.start_z_probe(std::stof(txt_min_z->value()), std::stof(txt_feed->value()));
+    });
+
+}
+
+void SenderApp::add_work_parameters_markup() {
+    // work parameters
+    info_layer->add<nanogui::Label>("Work parameters", "sans-bold", 20);
+    auto work_holder = info_layer->add<nanogui::Widget>();
+    work_holder->set_layout(
+            new nanogui::BoxLayout(nanogui::Orientation::Horizontal, nanogui::Alignment::Fill, 6, 6));
+
+    auto work_data_holder = work_holder->add<nanogui::Widget>();
+    work_data_holder->set_layout(
+            new nanogui::GridLayout(nanogui::Orientation::Horizontal, 2, nanogui::Alignment::Fill, 6, 6));
+
+    work_data_holder->add<nanogui::Label>("Offset", "sans-bold");
+    std::vector<std::string> offset_items = {"G54", "G55", "G56", "G57", "G58", "G59"};
+    cbo_work_offset = work_data_holder->add<nanogui::ComboBox>(offset_items);
+    cbo_work_offset->set_callback([&](int idx) {
+        refresh_offset();
+        update_dro();
+    });
+
+    work_data_holder->add<nanogui::Label>("Tool", "sans-bold");
+    std::vector<std::string> tool_items = {"None"};
+    cbo_tool = work_data_holder->add<nanogui::ComboBox>(tool_items);
+
+    auto work_btn_holder = work_holder->add<nanogui::Widget>();
+    work_btn_holder->set_layout(
+            new nanogui::GridLayout(nanogui::Orientation::Horizontal, 3, nanogui::Alignment::Fill, 0, 6));
+
+
+    btn_load_program = work_btn_holder->add<nanogui::Button>("Load");
+    btn_load_program->set_callback([&] {
+        auto path = nanogui::file_dialog(
+                {{"gcode", "G-Code files"},
+                 {"nc",    "G-Code files"},
+                 {"ngc",   "G-Code files"}}, true);
+
+        if (pgm.load_from_file(path)) {
+            init_program_geometry();
+            set_program_extents();
+            fill_heightmap_from_model();
+            update_grid();
+        } else {
+        }
+    });
+    btn_load_program->set_tooltip("Load program");
+
+    btn_check_program = work_btn_holder->add<nanogui::Button>("Check");
+//        btnCheckProgram->set_enabled(false);
+    btn_check_program->set_callback([&] {
+        cnc.check_program(pgm);
+    });
+    btn_check_program->set_tooltip("Check program");
+
+    btn_run_program = work_btn_holder->add<nanogui::Button>("Run");
+//        btnRunProgram->set_enabled(false);
+    btn_run_program->set_callback([&] {
+        cnc.run_program(pgm, "G" + std::to_string(cbo_work_offset->selected_index() + 54));
+    });
+    btn_run_program->set_tooltip("Execute program");
+
+}
+
+void SenderApp::add_status_markup() {
+    auto status_holder = info_layer->add<nanogui::Widget>();
+    status_holder->set_layout(
+            new nanogui::BoxLayout(nanogui::Orientation::Vertical, nanogui::Alignment::Fill, 0, 0));
+
+    auto status_text_holder = status_holder->add<nanogui::Widget>();
+    status_text_holder->set_layout(
+            new nanogui::GridLayout(nanogui::Orientation::Horizontal, 3, nanogui::Alignment::Fill, 0, 0));
+
+    status_text_holder->add<nanogui::Label>("Status", "sans-bold", 20);
+
+    txt_status = status_text_holder->add<nanogui::TextBox>();
+    txt_status->set_editable(false);
+    txt_status->set_fixed_width(300);
+
+    auto *btn_reset = status_text_holder->add<nanogui::Button>("Reset");
+    btn_reset->set_background_color(color_red);
+    btn_reset->set_callback([&] {
+        cnc.request_reset();
+    });
+
+    //
+    status_text_holder->add<nanogui::Label>("");
+
+    txt_message = status_text_holder->add<nanogui::TextBox>("");
+    txt_message->set_fixed_width(300);
+
+    status_text_holder->add<nanogui::Label>("");
+
+    // buttons
+    auto status_btn_holder = status_holder->add<nanogui::Widget>();
+    status_btn_holder->set_layout(
+            new nanogui::GridLayout(nanogui::Orientation::Horizontal, 2, nanogui::Alignment::Fill, 6, 6));
+
+    auto *btn_homing = new nanogui::Button(status_btn_holder, "Homing", FA_HOME);
+    btn_homing->set_callback([&] {
+        cnc.request_home();
+    });
+
+    auto *btn_unlock = new nanogui::Button(status_btn_holder, "Unlock", FA_UNLOCK);
+    btn_unlock->set_callback([&] {
+        cnc.request_unlock();
+    });
+
+    // buttons to change state
+    auto *btn_cycle_start = status_btn_holder->add<nanogui::Button>("Cycle Start", FA_PLAY);
+    btn_cycle_start->set_callback([&] {
+        cnc.request_cycle_start();
+    });
+    auto *btn_feed_hold = status_btn_holder->add<nanogui::Button>("Feed Hold", FA_PAUSE);
+    btn_feed_hold->set_callback([&] {
+        cnc.request_feed_hold();
+    });
+
+}
+
+void SenderApp::add_jogging_markup() {
+    // jogging
+    info_layer->add<nanogui::Label>("Jogging", "sans-bold", 20);
+    auto holder = new nanogui::Widget(info_layer);
+
+    holder->set_layout(
+            new nanogui::GridLayout(nanogui::Orientation::Horizontal, 3, nanogui::Alignment::Fill, 0, 0));
+
+    // feed and distance
+    auto jog_params_holder = holder->add<nanogui::Widget>();
+    jog_params_holder->set_layout(
+            new nanogui::GridLayout(nanogui::Orientation::Horizontal, 3, nanogui::Alignment::Fill, 0, 4));
+
+    jog_params_holder->add<nanogui::Label>("Feed", "sans-bold");
+    cbo_jog_feed_rates = jog_params_holder->add<nanogui::ComboBox>(jog_feed_rates);
+    cbo_jog_feed_rates->set_selected_index(2);
+    jog_params_holder->add<nanogui::Label>("mm/min");
+
+    jog_params_holder->add<nanogui::Label>("Distance", "sans-bold");
+    cbo_jog_distance = jog_params_holder->add<nanogui::ComboBox>(jog_distances);
+    cbo_jog_distance->set_selected_index(2);
+    jog_params_holder->add<nanogui::Label>("mm");
+
+    jog_params_holder->add<nanogui::Label>("Keyboard Jog", "sans-bold");
+    btn_keyboard_jog = jog_params_holder->add<nanogui::Button>("", FA_KEYBOARD);
+    btn_keyboard_jog->set_flags(nanogui::Button::ToggleButton);
+    jog_params_holder->add<nanogui::Label>("");
+
+    // X and Y
+    auto jog_btn_holder = holder->add<nanogui::Widget>();
+    jog_btn_holder->set_layout(
+            new nanogui::GridLayout(nanogui::Orientation::Horizontal, 3, nanogui::Alignment::Fill, 0, 6));
+
+    jog_btn_holder->add<nanogui::Label>("");
+    auto jog_btn = jog_btn_holder->add<nanogui::Button>("", FA_ARROW_ALT_CIRCLE_UP);
+    jog_btn->set_callback([&]() {
+        // FIXME: get rid of std::stof
+        cnc.request_jog_fixed(grbl::jog_direction::y_up,
+                              std::stof(jog_distances[cbo_jog_distance->selected_index()]),
+                              std::stof(jog_feed_rates[cbo_jog_feed_rates->selected_index()]));
+    });
+    jog_btn_holder->add<nanogui::Label>("");
+
+    jog_btn = jog_btn_holder->add<nanogui::Button>("", FA_ARROW_ALT_CIRCLE_LEFT);
+    jog_btn->set_callback([&]() {
+        // FIXME: get rid of std::stof
+        cnc.request_jog_fixed(grbl::jog_direction::x_down,
+                              std::stof(jog_distances[cbo_jog_distance->selected_index()]),
+                              std::stof(jog_feed_rates[cbo_jog_feed_rates->selected_index()]));
+    });
+
+    jog_btn = jog_btn_holder->add<nanogui::Button>("", FA_HOME);
+    jog_btn->set_callback([&]() {
+        cnc.go_to_zero(true, true, false);
+    });
+
+
+    jog_btn = jog_btn_holder->add<nanogui::Button>("", FA_ARROW_ALT_CIRCLE_RIGHT);
+    jog_btn->set_callback([&]() {
+        // FIXME: get rid of std::stof
+        cnc.request_jog_fixed(grbl::jog_direction::x_up,
+                              std::stof(jog_distances[cbo_jog_distance->selected_index()]),
+                              std::stof(jog_feed_rates[cbo_jog_feed_rates->selected_index()]));
+    });
+
+    jog_btn_holder->add<nanogui::Label>("");
+    jog_btn = jog_btn_holder->add<nanogui::Button>("", FA_ARROW_ALT_CIRCLE_DOWN);
+    jog_btn->set_callback([&]() {
+        // FIXME: get rid of std::stof
+        cnc.request_jog_fixed(grbl::jog_direction::y_down,
+                              std::stof(jog_distances[cbo_jog_distance->selected_index()]),
+                              std::stof(jog_feed_rates[cbo_jog_feed_rates->selected_index()]));
+    });
+    jog_btn_holder->add<nanogui::Label>("");
+
+
+    // z up/down
+    auto jog_z_btn_holder = holder->add<nanogui::Widget>();
+    jog_z_btn_holder->set_layout(
+            new nanogui::BoxLayout(nanogui::Orientation::Vertical, nanogui::Alignment::Fill, 0, 6));
+
+    jog_btn = jog_z_btn_holder->add<nanogui::Button>("", FA_CHEVRON_UP);
+    jog_btn->set_callback([&]() {
+        // FIXME: get rid of std::stof
+        cnc.request_jog_fixed(grbl::jog_direction::z_up,
+                              std::stof(jog_distances[cbo_jog_distance->selected_index()]),
+                              std::stof(jog_feed_rates[cbo_jog_feed_rates->selected_index()]));
+    });
+
+    jog_btn = jog_z_btn_holder->add<nanogui::Button>("", FA_HOME);
+    jog_btn->set_callback([&]() {
+        cnc.go_to_zero(false, false, true);
+    });
+
+    jog_btn = jog_z_btn_holder->add<nanogui::Button>("", FA_CHEVRON_DOWN);
+    jog_btn->set_callback([&]() {
+        // FIXME: get rid of std::stof
+        cnc.request_jog_fixed(grbl::jog_direction::z_down,
+                              std::stof(jog_distances[cbo_jog_distance->selected_index()]),
+                              std::stof(jog_feed_rates[cbo_jog_feed_rates->selected_index()]));
+    });
+}
+
+void SenderApp::add_dro_markup() {
+    dro_ss << std::setprecision(3) << std::fixed;
+
+    // DRO
+    info_layer->add<nanogui::Label>("DRO", "sans-bold", 20);
+    auto dro_holder = info_layer->add<nanogui::Widget>();
+    dro_holder->set_layout(
+            new nanogui::GridLayout(nanogui::Orientation::Horizontal, 1, nanogui::Alignment::Middle, 0, 6));
+
+    auto x_holder = dro_holder->add<nanogui::Widget>();
+    x_holder->set_layout(
+            new nanogui::BoxLayout(nanogui::Orientation::Horizontal, nanogui::Alignment::Middle, 0, 6));
+    auto lbl = x_holder->add<nanogui::Label>("X", "sans-bold", 20);
+    lbl->set_fixed_width(30);
+    mpos_x_text = x_holder->add<nanogui::TextBox>(std::to_string(cnc.get_status().machine_pos[0]));
+    mpos_x_text->set_fixed_width(200);
+    auto zero_btn = x_holder->add<nanogui::ToolButton>(FA_BAN);
+    zero_btn->set_flags(nanogui::Button::NormalButton);
+    zero_btn->set_tooltip("Zero axis");
+    zero_btn->set_callback([&]() {
+        cnc.zero_offset_axis(cbo_work_offset->selected_index(), 0);
+    });
+
+    auto y_holder = dro_holder->add<nanogui::Widget>();
+    y_holder->set_layout(
+            new nanogui::BoxLayout(nanogui::Orientation::Horizontal, nanogui::Alignment::Middle, 0, 6));
+    lbl = y_holder->add<nanogui::Label>("Y", "sans-bold", 20);
+    lbl->set_fixed_width(30);
+    mpos_y_text = y_holder->add<nanogui::TextBox>(std::to_string(cnc.get_status().machine_pos[1]));
+    mpos_y_text->set_fixed_width(200);
+    zero_btn = y_holder->add<nanogui::ToolButton>(FA_BAN);
+    zero_btn->set_flags(nanogui::Button::NormalButton);
+    zero_btn->set_tooltip("Zero axis");
+    zero_btn->set_callback([&]() {
+        cnc.zero_offset_axis(cbo_work_offset->selected_index(), 1);
+    });
+
+    auto z_holder = dro_holder->add<nanogui::Widget>();
+    z_holder->set_layout(
+            new nanogui::BoxLayout(nanogui::Orientation::Horizontal, nanogui::Alignment::Middle, 0, 6));
+    lbl = z_holder->add<nanogui::Label>("Z", "sans-bold", 20);
+    lbl->set_fixed_width(30);
+    mpos_z_text = z_holder->add<nanogui::TextBox>(std::to_string(cnc.get_status().machine_pos[0]));
+    mpos_z_text->set_fixed_width(200);
+    zero_btn = z_holder->add<nanogui::ToolButton>(FA_BAN);
+    zero_btn->set_flags(nanogui::Button::NormalButton);
+    zero_btn->set_tooltip("Zero axis");
+    zero_btn->set_callback([&]() {
+        cnc.zero_offset_axis(cbo_work_offset->selected_index(), 2);
+    });
+
+    auto axis_btn_holder = dro_holder->add<Widget>();
+    axis_btn_holder->set_layout(
+            new nanogui::BoxLayout(nanogui::Orientation::Horizontal, nanogui::Alignment::Middle, 0, 6));
+
+    auto zero_all_btn = axis_btn_holder->add<nanogui::Button>("Zero all");
+    zero_all_btn->set_callback([&]() {
+        cnc.zero_offset(cbo_work_offset->selected_index());
+    });
+
+    auto goto_zero_btn = axis_btn_holder->add<nanogui::Button>("Goto 0");
+    goto_zero_btn->set_callback([&]() {
+        cnc.go_to_zero(true, true, true);
+    });
+}
+
+void SenderApp::add_program_extents() {
+    dro_ss << std::setprecision(3) << std::fixed;
+
+    // Program extents
+    info_layer->add<nanogui::Label>("Program extents", "sans-bold", 20);
+    auto extents_holder = info_layer->add<nanogui::Widget>();
+    extents_holder->set_layout(
+            new nanogui::GridLayout(nanogui::Orientation::Horizontal, 3, nanogui::Alignment::Fill, 4, 4));
+
+    extents_holder->add<nanogui::Label>("X", "sans-bold", 20);
+    extents_min_x = extents_holder->add<nanogui::TextBox>("");
+    extents_max_x = extents_holder->add<nanogui::TextBox>("");
+
+    extents_holder->add<nanogui::Label>("Y", "sans-bold", 20);
+    extents_min_y = extents_holder->add<nanogui::TextBox>("");
+    extents_max_y = extents_holder->add<nanogui::TextBox>("");
+
+    extents_holder->add<nanogui::Label>("Z", "sans-bold", 20);
+    extents_min_z = extents_holder->add<nanogui::TextBox>("");
+    extents_max_z = extents_holder->add<nanogui::TextBox>("");
+}
+
+void SenderApp::save_heightmap(const grbl::heightmap &grid, std::string path) {
+    std::ofstream out(path);
+    if (out) {
+        out << "from_x:" << grid.from_x << std::endl;
+        out << "from_y:" << grid.from_y << std::endl;
+        out << "to_x:" << grid.to_x << std::endl;
+        out << "to_y:" << grid.to_y << std::endl;
+        out << "resolution:" << grid.resolution << std::endl;
+        out << "probes:" << grid.vertices.size() << std::endl;
+        for (auto &v: grid.vertices) {
+            out << v.x << ":" << v.y << ":" << v.z << std::endl;
+        }
+    }
+}
+
+grbl::heightmap SenderApp::load_heightmap(std::string path) {
+    grbl::heightmap result{};
+
+    std::ifstream in_file(path);
+    if (in_file) {
+        float from_x, from_y;
+        float to_x, to_y;
+        float resolution;
+        size_t probe_location = 0;
+
+        for (std::string line; std::getline(in_file, line);) {
+            auto pieces = split_string(line, ":");
+            if (pieces[0] == "from_x") {
+                from_x = std::stof(pieces[1]);
+            } else if (pieces[0] == "from_y") {
+                from_y = std::stof(pieces[1]);
+            } else if (pieces[0] == "to_x") {
+                to_x = std::stof(pieces[1]);
+            } else if (pieces[0] == "to_y") {
+                to_y = std::stof(pieces[1]);
+            } else if (pieces[0] == "resolution") {
+                resolution = std::stof(pieces[1]);
+            } else if (pieces[0] == "probes") {
+                result = grbl::heightmap::from_params(from_x, from_y, to_x, to_y, resolution);
+            } else {
+                result.vertices[probe_location].x = std::stof(pieces[0]);
+                result.vertices[probe_location].y = std::stof(pieces[1]);
+                result.vertices[probe_location].z = std::stof(pieces[2]);
+                probe_location++;
+            }
+        }
+    }
+
+    return result;
+}
+
+void SenderApp::fill_heightmap_controls_from_grid(const grbl::heightmap &grid) const {
+    txt_heightmap_from_x->set_value(std::to_string(grid.from_x));
+    txt_heightmap_from_y->set_value(std::to_string(grid.from_y));
+    txt_heightmap_to_x->set_value(std::to_string(grid.to_x));
+    txt_heightmap_to_y->set_value(std::to_string(grid.to_y));
+    txt_heightmap_res->set_value(std::to_string(grid.resolution));
+}
+
+void SenderApp::add_heightmap_markup() {
+    heightmap_layer->add<nanogui::Label>("Grid definition", "sans-bold", 20);
+    auto heightmap_params_holder = heightmap_layer->add<nanogui::Widget>();
+    heightmap_params_holder->set_layout(
+            new nanogui::BoxLayout(nanogui::Orientation::Vertical, nanogui::Alignment::Fill, 4, 4));
+
+    // grid size
+    auto grid_size_holder = heightmap_params_holder->add<Widget>();
+    grid_size_holder->set_layout(
+            new nanogui::GridLayout(nanogui::Orientation::Horizontal, 3, nanogui::Alignment::Middle, 4, 4));
+
+    grid_size_holder->add<nanogui::Label>("", "sans-bold", 20);
+    grid_size_holder->add<nanogui::Label>("X", "sans-bold", 20);
+    grid_size_holder->add<nanogui::Label>("Y", "sans-bold", 20);
+
+    grid_size_holder->add<nanogui::Label>("From", "sans-bold", 20);
+    txt_heightmap_from_x = grid_size_holder->add<nanogui::TextBox>("");
+    txt_heightmap_from_x->set_editable(true);
+    txt_heightmap_from_x->set_fixed_width(150);
+    txt_heightmap_from_y = grid_size_holder->add<nanogui::TextBox>("");
+    txt_heightmap_from_y->set_editable(true);
+    txt_heightmap_from_y->set_fixed_width(150);
+
+    grid_size_holder->add<nanogui::Label>("To", "sans-bold", 20);
+    txt_heightmap_to_x = grid_size_holder->add<nanogui::TextBox>("");
+    txt_heightmap_to_x->set_editable(true);
+    txt_heightmap_to_x->set_fixed_width(150);
+    txt_heightmap_to_y = grid_size_holder->add<nanogui::TextBox>("");
+    txt_heightmap_to_y->set_editable(true);
+    txt_heightmap_to_y->set_fixed_width(150);
+
+    grid_size_holder->add<nanogui::Label>("");
+    auto btn = grid_size_holder->add<nanogui::Button>("Fetch from model");
+    btn->set_callback([&]() {
+        fill_heightmap_from_model();
+    });
+    auto btn_load_heightmap = grid_size_holder->add<nanogui::Button>("Load from file");
+    btn_load_heightmap->set_callback([&]() {
+        auto path = nanogui::file_dialog(
+                {{"hmap", "Heightmap files"}
+                }, true);
+        if (!path.empty()) {
+            heightmap_grid = load_heightmap(path);
+            fill_heightmap_controls_from_grid(heightmap_grid);
+            renderer.update_grid(heightmap_grid);
+        }
+    });
+
+    txt_heightmap_from_x->set_callback([&](const std::string &new_value) {
+        update_grid();
+        return true;
+    });
+    txt_heightmap_from_y->set_callback([&](const std::string &new_value) {
+        update_grid();
+        return true;
+    });
+
+    txt_heightmap_to_x->set_callback([&](const std::string &new_value) {
+        update_grid();
+        return true;
+    });
+    txt_heightmap_to_y->set_callback([&](const std::string &new_value) {
+        update_grid();
+        return true;
+    });
+
+
+    // grid resolution
+    auto grid_res_holder = heightmap_params_holder->add<Widget>();
+    grid_res_holder->set_layout(
+            new nanogui::BoxLayout(nanogui::Orientation::Horizontal, nanogui::Alignment::Middle, 4, 4));
+    grid_res_holder->add<nanogui::Label>("Grid resolution", "sans-bold", 20);
+    txt_heightmap_res = grid_res_holder->add<nanogui::TextBox>("5");
+    txt_heightmap_res->set_editable(true);
+    txt_heightmap_res->set_fixed_width(150);
+    txt_heightmap_res->set_callback([&](const std::string &new_value) {
+        update_grid();
+        return true;
+    });
+    grid_res_holder->add<nanogui::Label>("mm", "sans-bold", 20);
+
+    // business params
+    auto heightmap_business_holder = heightmap_params_holder->add<nanogui::Widget>();
+    heightmap_business_holder->set_layout(
+            new nanogui::GridLayout(nanogui::Orientation::Horizontal, 3, nanogui::Alignment::Fill, 4, 4));
+
+    heightmap_business_holder->add<nanogui::Label>("Clearance height Z", "sans-bold", 20);
+    txt_clearance_height = heightmap_business_holder->add<nanogui::TextBox>("1.5");
+    txt_clearance_height->set_editable(true);
+    heightmap_business_holder->add<nanogui::Label>("", "sans-bold");
+
+    heightmap_business_holder->add<nanogui::Label>("Start probing at Z", "sans-bold", 20);
+    txt_start_probing_at = heightmap_business_holder->add<nanogui::TextBox>("0.5");
+    txt_start_probing_at->set_editable(true);
+    heightmap_business_holder->add<nanogui::Label>("", "sans-bold");
+
+    heightmap_business_holder->add<nanogui::Label>("Max negative Z", "sans-bold", 20);
+    txt_max_negative_z = heightmap_business_holder->add<nanogui::TextBox>("-1.0");
+    txt_max_negative_z->set_editable(true);
+    heightmap_business_holder->add<nanogui::Label>("(when to fail probing)", "sans-bold");
+
+    heightmap_business_holder->add<nanogui::Label>("Final Z safety height", "sans-bold", 20);
+    txt_final_z_height = heightmap_business_holder->add<nanogui::TextBox>("15");
+    txt_final_z_height->set_editable(true);
+    heightmap_business_holder->add<nanogui::Label>("", "sans-bold");
+
+    heightmap_business_holder->add<nanogui::Label>("", "sans-bold");
+    auto btn_start_probing = heightmap_business_holder->add<nanogui::Button>("Start Probing");
+    btn_start_probing->set_callback([&]() {
+        cnc.probe_heightmap(heightmap_grid);
+    });
+    auto btn_save_heightmap = heightmap_business_holder->add<nanogui::Button>("Save heightmap");
+    btn_save_heightmap->set_callback([&]() {
+        auto path = nanogui::file_dialog(
+                {{"hmap", "Heightmap files"}
+                }, true);
+        if (!path.empty()) {
+            save_heightmap(heightmap_grid, path);
+        }
+    });
+}
+
+void SenderApp::fill_heightmap_from_model() const {
+    auto min = renderer.get_extents_min();
+    auto max = renderer.get_extents_max();
+    txt_heightmap_from_x->set_value(std::to_string(min.x));
+    txt_heightmap_from_y->set_value(std::to_string(min.y));
+    txt_heightmap_to_x->set_value(std::to_string(max.x));
+    txt_heightmap_to_y->set_value(std::to_string(max.y));
+}
+
+void SenderApp::update_grid() {
+    auto from_x = std::stof(txt_heightmap_from_x->value());
+    auto from_y = std::stof(txt_heightmap_from_y->value());
+    auto to_x = std::stof(txt_heightmap_to_x->value());
+    auto to_y = std::stof(txt_heightmap_to_y->value());
+    auto res = std::stof(txt_heightmap_res->value());
+
+    if (from_x != heightmap_grid.from_x ||
+        from_y != heightmap_grid.from_y ||
+        to_x != heightmap_grid.to_x ||
+        to_y != heightmap_grid.to_y ||
+        res != heightmap_grid.resolution) {
+        heightmap_grid = std::move(grbl::heightmap::from_params(from_x, from_y, to_x, to_y, res));
+        renderer.update_grid(heightmap_grid);
+    }
+}
+
+void SenderApp::add_pins_markup() {
+    // Pins
+    info_layer->add<nanogui::Label>("Pins", "sans-bold", 20);
+    auto pins_holder = info_layer->add<nanogui::Widget>();
+    pins_holder->set_layout(
+            new nanogui::BoxLayout(nanogui::Orientation::Horizontal, nanogui::Alignment::Fill, 4, 4));
+
+    btn_pin_door = pins_holder->add<nanogui::ToolButton>(0, "D");
+//        btn_pin_door->set_enabled(false);
+    btn_pin_door->set_flags(nanogui::Button::Flags::NormalButton);
+
+    btn_pin_hold = pins_holder->add<nanogui::ToolButton>(0, "H");
+//        btn_pin_hold->set_enabled(false);
+    btn_pin_hold->set_flags(nanogui::Button::Flags::NormalButton);
+
+    btn_pin_reset = pins_holder->add<nanogui::ToolButton>(0, "R");
+//        btn_pin_reset->set_enabled(false);
+    btn_pin_reset->set_flags(nanogui::Button::Flags::NormalButton);
+
+    btn_pin_cycle_start = pins_holder->add<nanogui::ToolButton>(0, "S");
+//        btn_pin_cycle_start->set_enabled(false);
+    btn_pin_cycle_start->set_flags(nanogui::Button::Flags::NormalButton);
+
+    auto a = pins_holder->add<nanogui::Label>("");
+    a->set_fixed_width(30);
+
+    btn_pin_limit_x = pins_holder->add<nanogui::ToolButton>(0, "X");
+//        btn_pin_limit_x->set_enabled(false);
+    btn_pin_limit_x->set_flags(nanogui::Button::Flags::NormalButton);
+
+    btn_pin_limit_y = pins_holder->add<nanogui::ToolButton>(0, "Y");
+//        btn_pin_limit_y->set_enabled(false);
+    btn_pin_limit_y->set_flags(nanogui::Button::Flags::NormalButton);
+
+    btn_pin_limit_z = pins_holder->add<nanogui::ToolButton>(0, "Z");
+//        btn_pin_limit_z->set_enabled(false);
+    btn_pin_limit_z->set_flags(nanogui::Button::Flags::NormalButton);
+
+    btn_pin_probe = pins_holder->add<nanogui::ToolButton>(0, "P");
+//        btn_pin_probe->set_enabled(false);
+    btn_pin_probe->set_flags(nanogui::Button::Flags::NormalButton);
+}
+
+void SenderApp::refresh_offset() {
+    auto offset_name = "G" + std::to_string(cbo_work_offset->selected_index() + 54);
+    cnc.set_work_offset(offset_name);
+}
+
+void SenderApp::fill_in_parameters() {
+    parameters_vscroll = new nanogui::VScrollPanel(tab_widget);
+    tab_widget->append_tab("Parameters", parameters_vscroll);
+
+    parameters_layer = new Widget(parameters_vscroll);
+    parameters_layer->set_layout(
+            new nanogui::GridLayout(nanogui::Orientation::Horizontal, 1, nanogui::Alignment::Middle));
+
+    auto &parameters = cnc.get_parameters();
+
+    for (auto &entry: parameters) {
+        auto w = parameters_layer->add<Widget>();
+        w->set_layout(new nanogui::BoxLayout(nanogui::Orientation::Horizontal, nanogui::Alignment::Middle, 2, 2));
+        auto x = w->add<nanogui::Label>(entry.first, "sans-bold", 20);
+        x->set_fixed_width(50);
+
+        auto y = w->add<nanogui::TextBox>(entry.second);
+        y->set_editable(true);
+        y->set_fixed_width(200);
+
+        auto z = w->add<nanogui::Button>("", FA_SAVE);
+//            z->set_flags(Button::Flags::NormalButton); // no toggle, please
+        z->set_tooltip("save");
+    }
+}
+
+void SenderApp::fill_in_settings() {
+    settings_vscroll = new nanogui::VScrollPanel(tab_widget);
+    tab_widget->append_tab("Settings", settings_vscroll);
+
+    settings_layer = new nanogui::Widget(settings_vscroll);
+    settings_layer->set_layout(
+            new nanogui::GridLayout(nanogui::Orientation::Horizontal, 1, nanogui::Alignment::Middle));
+
+    auto &settings = cnc.get_settings();
+
+    for (auto &s: settings) {
+        auto w = settings_layer->add<nanogui::Widget>();
+        w->set_layout(new nanogui::BoxLayout(nanogui::Orientation::Horizontal, nanogui::Alignment::Middle, 2, 2));
+        auto x = w->add<nanogui::Label>(s.first, "sans-bold", 20);
+        x->set_fixed_width(40);
+
+        auto desc = grbl::setting_description(std::stoi(s.first.substr(1)));
+
+        auto y = w->add<nanogui::TextBox>(s.second);
+        y->set_editable(true);
+        y->set_tooltip(desc);
+        y->set_fixed_width(150);
+
+        auto z = w->add<nanogui::ToolButton>(FA_SAVE);
+        z->set_flags(nanogui::Button::Flags::NormalButton); // no toggle, please
+        z->set_tooltip("save");
+
+        auto t = w->add<nanogui::TextArea>();
+        t->set_fixed_width(200);
+        t->set_fixed_height(20);
+        t->clear();
+        t->append(desc.substr(0, desc.find_first_of('\n')));
+    }
+}
+
+void SenderApp::init_program_geometry() {
+    renderer.update(pgm, cnc);
+
+    auto max_pos = renderer.get_extents_max();
+    auto min_pos = renderer.get_extents_min();
+
+    cam_target = (max_pos - min_pos) / 2.0f;
+    cam_zoom = (max_pos.x - min_pos.x);
+    cam_src_rotation = glm::quat(1.0, 0.0, 0.0, 0.0);
+}
+
+void SenderApp::set_program_extents() const {
+    auto min = renderer.get_extents_min();
+    auto max = renderer.get_extents_max();
+
+    extents_min_x->set_value(std::to_string(min.x));
+    extents_max_x->set_value(std::to_string(max.x));
+
+    extents_min_y->set_value(std::to_string(min.y));
+    extents_max_y->set_value(std::to_string(max.y));
+
+    extents_min_z->set_value(std::to_string(min.z));
+    extents_max_z->set_value(std::to_string(max.z));
+}
+
+bool SenderApp::resize_event(const nanogui::Vector2i &size) {
+//        window->set_fixed_height(this->height() / 2);
+    tab_widget->set_fixed_height((this->height() - 30));
+    perform_layout();
+
+    return Screen::resize_event(size);
+}
+
+void SenderApp::update_dro() {
+    auto work_pos = cnc.get_work_pos();
+
+    dro_ss.str("");
+    dro_ss << work_pos[0];
+    mpos_x_text->set_value(dro_ss.str());
+
+    dro_ss.str("");
+    dro_ss << work_pos[1];
+    mpos_y_text->set_value(dro_ss.str());
+
+    dro_ss.str("");
+    dro_ss << work_pos[2];
+    mpos_z_text->set_value(dro_ss.str());
+}
+
+bool SenderApp::keyboard_event(int key, int scancode, int action, int modifiers) {
+    if (Screen::keyboard_event(key, scancode, action, modifiers))
+        return true;
+
+//        if (key == GLFW_KEY_ESCAPE && action == GLFW_PRESS) {
+//            set_visible(false);
+//            return true;
+//        }
+
+    if (key == GLFW_KEY_SPACE && action == GLFW_PRESS && !window->mouse_focused()) {
+        // reset trackball rotation
+        cam_src_rotation = glm::quat(1, 0, 0, 0);
+    }
+
+    auto new_jog = jog;
+
+    if (key == GLFW_KEY_LEFT_SHIFT) {
+        if (action == GLFW_PRESS) {
+            new_jog.speed_fast_pressed = true;
+        } else if (action == GLFW_RELEASE) {
+            new_jog.speed_fast_pressed = false;
+        }
+    }
+
+    if (key == GLFW_KEY_LEFT_CONTROL) {
+        if (action == GLFW_PRESS) {
+            new_jog.speed_slow_pressed = true;
+        } else if (action == GLFW_RELEASE) {
+            new_jog.speed_slow_pressed = false;
+        }
+    }
+
+    if (key == GLFW_KEY_UP) {
+        if (action == GLFW_PRESS) {
+            new_jog.up_pressed = true;
+        } else if (action == GLFW_RELEASE) {
+            new_jog.up_pressed = false;
+        }
+    }
+
+    if (key == GLFW_KEY_DOWN) {
+        if (action == GLFW_PRESS) {
+            new_jog.down_pressed = true;
+        } else if (action == GLFW_RELEASE) {
+            new_jog.down_pressed = false;
+        }
+    }
+
+    if (key == GLFW_KEY_LEFT) {
+        if (action == GLFW_PRESS) {
+            new_jog.left_pressed = true;
+        } else if (action == GLFW_RELEASE) {
+            new_jog.left_pressed = false;
+        }
+    }
+
+    if (key == GLFW_KEY_RIGHT) {
+        if (action == GLFW_PRESS) {
+            new_jog.right_pressed = true;
+        } else if (action == GLFW_RELEASE) {
+            new_jog.right_pressed = false;
+        }
+    }
+
+    if (key == GLFW_KEY_PAGE_UP) {
+        if (action == GLFW_PRESS) {
+            new_jog.z_up_pressed = true;
+        } else if (action == GLFW_RELEASE) {
+            new_jog.z_up_pressed = false;
+        }
+    }
+
+    if (key == GLFW_KEY_PAGE_DOWN) {
+        if (action == GLFW_PRESS) {
+            new_jog.z_down_pressed = true;
+        } else if (action == GLFW_RELEASE) {
+            new_jog.z_down_pressed = false;
+        }
+    }
+
+    if (btn_keyboard_jog->pushed() && jog != new_jog) {
+        cnc.request_jog(new_jog);
+        jog = new_jog;
+    }
+
+    return false;
+}
+
+bool
+SenderApp::mouse_motion_event(const nanogui::Vector2i &p, const nanogui::Vector2i &rel, int button, int modifiers) {
+    auto result = Widget::mouse_motion_event(p, rel, button, modifiers);
+    if (window->mouse_focused()) {
+        return result;
+    } else {
+//            std::cout << "Mouse motion p:" << p << ", rel:" << rel << ", button:" << button << ", .modifiers:" << modifiers << std::endl;
+        bool is_rotating = button == 1;
+        bool is_panning = button == 2;
+        if (is_rotating) {
+            if (abs(rel.x()) > abs(rel.y())) {
+                cam_src_rotation *= glm::angleAxis(rel.x() / 100.0f, glm::vec3(0, 1, 0));
+            } else {
+                cam_src_rotation *= glm::angleAxis(rel.y() / 100.0f, glm::vec3(1, 0, 0));
+            }
+
+        } else if (is_panning) {
+            cam_pan.x += (float) rel.x() / 10.0f;
+            cam_pan.y -= (float) rel.y() / 10.0f;
+        }
+        return true;
+    }
+}
+
+bool SenderApp::scroll_event(const nanogui::Vector2i &p, const nanogui::Vector2f &rel) {
+    if (window->mouse_focused()) {
+        return Widget::scroll_event(p, rel);
+    } else {
+//            std::cout << "Scroll event: p:" << p << ", rel:" << rel << std::endl;
+        cam_zoom -= rel.y() * cam_zoom / 10.0f;
+        cam_zoom = std::max(cam_zoom, 0.1f);
+
+        return true;
+    }
+}
+
+void SenderApp::draw(NVGcontext *ctx) {
+    std::shared_ptr<grbl::machine_event> event;
+    while ((event = cnc.pop_event()) != nullptr) {
+        switch (event->type) {
+            case grbl::machine_event_type::connected:
+                break;
+            case grbl::machine_event_type::disconnected:
+                break;
+            case grbl::machine_event_type::report_received: {
+
+                auto ev = dynamic_cast<grbl::machine_event_report_received *>(event.get());
+
+                txt_status->set_value(grbl::status_to_string(cnc.get_status().status));
+
+                if (cnc.get_status().status == grbl::machine_status::alarm) {
+                    txt_status->set_tooltip(grbl::alarm_to_string(last_alarm));
+                } else {
+                    txt_status->set_tooltip(cnc.get_status().sub_status);
+                }
+
+                // FIXME: ugly way of retrieving the bg color
+                btn_pin_door->set_background_color(
+                        ev->report.signals.bit.door ? color_red : btn_load_program->background_color());
+                btn_pin_hold->set_background_color(
+                        ev->report.signals.bit.hold ? color_red : btn_load_program->background_color());
+                btn_pin_reset->set_background_color(
+                        ev->report.signals.bit.soft_reset ? color_red : btn_load_program->background_color());
+                btn_pin_cycle_start->set_background_color(
+                        ev->report.signals.bit.cycle_start ? color_red : btn_load_program->background_color());
+                btn_pin_limit_x->set_background_color(
+                        ev->report.signals.bit.x_limit ? color_red : btn_load_program->background_color());
+                btn_pin_limit_y->set_background_color(
+                        ev->report.signals.bit.y_limit ? color_red : btn_load_program->background_color());
+                btn_pin_limit_z->set_background_color(
+                        ev->report.signals.bit.z_limit ? color_red : btn_load_program->background_color());
+                btn_pin_probe->set_background_color(
+                        ev->report.signals.bit.probe ? color_red : btn_load_program->background_color());
+
+                update_dro();
+                last_report = ev->report;
+                break;
+            }
+            case grbl::machine_event_type::banner:
+                break;
+            case grbl::machine_event_type::message: {
+                auto ev = dynamic_cast<grbl::machine_event_message *>(event.get());
+                txt_message->set_value(ev->message);
+                set_caption(ev->message);
+                break;
+            }
+            case grbl::machine_event_type::alarm: {
+                auto ev = dynamic_cast<grbl::machine_event_alarm *>(event.get());
+                last_alarm = ev->alarm;
+                break;
+            }
+            case grbl::machine_event_type::init_completed:
+                fill_in_settings();
+                fill_in_parameters();
+
+                perform_layout();
+
+                refresh_offset();
+                update_dro();
+                break;
+            case grbl::machine_event_type::run_completed: {
+                auto ev = dynamic_cast<grbl::machine_event_run_completed *>(event.get());
+                btn_run_program->set_background_color(ev->success ? color_green : color_red);
+                if (ev->success) {
+                    new nanogui::MessageDialog(this, nanogui::MessageDialog::Type::Information, "Run result",
+                                               "Program executed successfully");
+                } else {
+                    std::stringstream ss;
+                    auto i = pgm.instruction_at(ev->failed_index);
+                    ss << "Program execution failed at line " << i.line << " (" << i.command << "). Error: "
+                       << ev->error << ", "
+                       << grbl::error_to_string(ev->error);
+                    new nanogui::MessageDialog(this, nanogui::MessageDialog::Type::Warning, "Run result", ss.str());
+                }
+                break;
+            }
+            case grbl::machine_event_type::check_completed: {
+                auto ev = dynamic_cast<grbl::machine_event_check_completed *>(event.get());
+
+                btn_check_program->set_background_color(ev->success ? color_green : color_red);
+                if (ev->success) {
+                    btn_run_program->set_enabled(true);
+                    new nanogui::MessageDialog(this, nanogui::MessageDialog::Type::Information, "Check result",
+                                               "Program checked successfully");
+                } else {
+                    btn_run_program->set_enabled(false);
+                    std::stringstream ss;
+                    auto i = pgm.instruction_at(ev->failed_index);
+                    ss << "Program check failed at line " << i.line << " (" << i.command << "). Error: "
+                       << ev->error << ", "
+                       << grbl::error_to_string(ev->error);
+                    new nanogui::MessageDialog(this, nanogui::MessageDialog::Type::Warning, "Check result",
+                                               ss.str());
+                }
+                break;
+            }
+            case grbl::machine_event_type::settings_reloaded:
+                break;
+            case grbl::machine_event_type::parameters_reloaded:
+                refresh_offset();
+                update_dro();
+                break;
+            case grbl::machine_event_type::probe_result: {
+                auto ev = dynamic_cast<grbl::machine_event_probe_result *>(event.get());
+
+                std::stringstream ss;
+                ss << "Probing ended. Result: " << std::boolalpha << ev->probe_touched << " at coords: ";
+                for (float probe_coord: ev->probe_coords) {
+                    ss << probe_coord << ", ";
+                }
+                new nanogui::MessageDialog(this, nanogui::MessageDialog::Type::Warning, "Probe result", ss.str());
+                break;
+            }
+            case grbl::machine_event_type::heightmap_probe_acquired: {
+                std::cout << "Updating grid" << std::endl;
+                auto ev = dynamic_cast<grbl::machine_event_heightmap_probe_acquired *>(event.get());
+                renderer.update_grid(*ev->grid);
+                break;
+            }
+        }
+    }
+
+    Widget::draw(ctx);
+}
+
+void SenderApp::draw_contents() {
+    auto fb_size = framebuffer_size();
+
+    // start rendering
+    m_render_pass->resize(framebuffer_size());
+    m_render_pass->begin();
+
+    renderer.update(pgm, cnc);
+    // compute mvp
+    glm::mat4 projection = glm::perspective(45.0f * glm::pi<float>() / 180.0f,
+                                            (float) fb_size.x() / (float) fb_size.y(),
+                                            0.1f,
+                                            10000.f);
+
+    glm::mat4 view = glm::translate(glm::mat4(1.0f), glm::vec3(0, 0, -cam_zoom)) *
+                     glm::toMat4(cam_src_rotation) *
+                     glm::translate(glm::mat4(1.0f), cam_pan - cam_target);
+
+    glm::mat4 model = glm::mat4(1.0f);
+    glm::mat3 normal_mat = glm::inverseTranspose(glm::mat3(view * model));
+
+    renderer.render(model, view, projection, normal_mat, glm::vec2(fb_size.x(), fb_size.y()));
+
+    m_render_pass->end();
+}
diff --git a/sender_app.h b/sender_app.h
new file mode 100644
index 0000000..a8779f1
--- /dev/null
+++ b/sender_app.h
@@ -0,0 +1,144 @@
+#pragma once
+
+#include <nanogui/opengl.h>
+#include <nanogui/screen.h>
+#include <nanogui/window.h>
+#include <nanogui/layout.h>
+#include <nanogui/label.h>
+#include <nanogui/button.h>
+#include <nanogui/popupbutton.h>
+#include <nanogui/progressbar.h>
+#include <nanogui/messagedialog.h>
+#include <nanogui/texture.h>
+#include <nanogui/textarea.h>
+#include <nanogui/textbox.h>
+#include <nanogui/tabwidget.h>
+#include <nanogui/shader.h>
+#include <nanogui/renderpass.h>
+#include <iostream>
+#include <memory>
+#include "grbl_machine.h"
+#include "render.h"
+#include "glm/glm.hpp"
+
+#define STB_IMAGE_STATIC
+#define STB_IMAGE_IMPLEMENTATION
+#if defined(_MSC_VER)
+#  pragma warning (disable: 4505) // don't warn about dead code in stb_image.h
+#elif defined(__GNUC__)
+#   pragma GCC diagnostic ignored "-Wunused-function"
+#endif
+
+#include <stb_image.h>
+#include "grbl.h"
+#include <gtest/gtest.h>
+#include <regex>
+#include "grbl_machine.h"
+#include "string_utils.h"
+#include "render.h"
+#include "glm/gtx/quaternion.hpp"
+#include "nanogui/nanogui.h"
+#include "glm/gtc/matrix_inverse.hpp"
+#include "heightmap.h"
+#include <glm/ext/quaternion_float.hpp>
+#include <glm/ext/quaternion_trigonometric.hpp>
+#include <glm/vec3.hpp> // glm::vec3
+#include <glm/ext/matrix_transform.hpp> // glm::translate, glm::rotate, glm::scale
+#include <glm/ext/matrix_clip_space.hpp> // glm::perspective
+#include <glm/ext/scalar_constants.hpp> // glm::pi
+#include <fstream>
+
+class SenderApp : public nanogui::Screen {
+public:
+    SenderApp();
+
+private:
+    void add_z_probe_markup();
+    void add_work_parameters_markup();
+    void add_status_markup();
+    void add_jogging_markup();
+    void add_dro_markup();
+    void add_program_extents();
+    void add_heightmap_markup();
+    void add_pins_markup();
+
+    static void save_heightmap(const grbl::heightmap &grid, std::string path);
+    grbl::heightmap load_heightmap(std::string path);
+
+    void update_dro();
+    void update_grid();
+    void refresh_offset();
+
+    void fill_heightmap_controls_from_grid(const grbl::heightmap &grid) const;
+    void fill_heightmap_from_model() const;
+    void fill_in_parameters();
+    void fill_in_settings();
+    void init_program_geometry();
+    void set_program_extents() const;
+
+    bool resize_event(const nanogui::Vector2i &size) override;
+    bool keyboard_event(int key, int scancode, int action, int modifiers) override;
+    bool mouse_motion_event(const nanogui::Vector2i &p,
+                            const nanogui::Vector2i &rel,
+                            int button,
+                            int modifiers) override;
+    bool scroll_event(const nanogui::Vector2i &p, const nanogui::Vector2f &rel) override;
+    void draw(NVGcontext *ctx) override;
+    void draw_contents() override;
+
+    grbl::machine cnc{};
+private:
+
+    nanogui::TextBox *txt_min_z = nullptr, *txt_feed = nullptr;
+    nanogui::TextBox *txt_heightmap_from_x = nullptr, *txt_heightmap_from_y = nullptr;
+    nanogui::TextBox *txt_heightmap_to_x = nullptr, *txt_heightmap_to_y = nullptr;
+    nanogui::TextBox *txt_heightmap_res = nullptr;
+    nanogui::TextBox *txt_clearance_height = nullptr, *txt_start_probing_at = nullptr, *txt_max_negative_z = nullptr, *txt_final_z_height = nullptr;
+    nanogui::Window *window = nullptr;
+    nanogui::TextBox *txt_status = nullptr;
+    nanogui::TextBox *txt_message = nullptr;
+    nanogui::Color color_red = nanogui::Color(255, 0, 0, 255);
+    nanogui::Color color_green = nanogui::Color(0, 255, 0, 255);
+    nanogui::Button *btn_load_program = nullptr, *btn_check_program = nullptr, *btn_run_program = nullptr;
+
+    nanogui::Widget *info_layer = nullptr, *heightmap_layer = nullptr;
+    nanogui::TabWidget *tab_widget = nullptr;
+    nanogui::VScrollPanel *settings_vscroll = nullptr;
+    nanogui::Widget *settings_layer = nullptr;
+
+    nanogui::VScrollPanel *parameters_vscroll = nullptr;
+    nanogui::Widget *parameters_layer = nullptr;
+    nanogui::TextBox *mpos_x_text = nullptr, *mpos_y_text = nullptr, *mpos_z_text = nullptr;
+    nanogui::ComboBox *cbo_work_offset = nullptr, *cbo_tool = nullptr, *cbo_jog_feed_rates = nullptr, *cbo_jog_distance = nullptr;
+
+    nanogui::ToolButton *btn_pin_door = nullptr, *btn_pin_hold = nullptr, *btn_pin_reset = nullptr, *btn_pin_cycle_start = nullptr;
+    nanogui::ToolButton *btn_pin_limit_x = nullptr, *btn_pin_limit_y = nullptr, *btn_pin_limit_z = nullptr, *btn_pin_probe = nullptr;
+
+    nanogui::Button *btn_keyboard_jog = nullptr;
+    std::stringstream dro_ss;
+    grbl::heightmap heightmap_grid;
+
+    nanogui::TextBox *extents_min_x = nullptr, *extents_max_x = nullptr;
+    nanogui::TextBox *extents_min_y = nullptr, *extents_max_y = nullptr;
+    nanogui::TextBox *extents_min_z = nullptr, *extents_max_z = nullptr;
+
+    nanogui::ProgressBar *m_progress = nullptr;
+    nanogui::ref<nanogui::RenderPass> m_render_pass;
+
+    using ImageHolder = std::unique_ptr<uint8_t[], void (*)(void *)>;
+    std::vector<std::pair<nanogui::ref<nanogui::Texture>, ImageHolder>> m_images;
+
+    std::vector<std::string> jog_distances = {"0.01", "0.1", "1", "10"};
+    std::vector<std::string> jog_feed_rates = {"5", "100", "500", "1000"};
+
+    int last_alarm = 0;
+
+    grbl::program pgm{};
+    grbl::realtime_status_report last_report;
+    grbl::jog_state jog;
+    grbl::program_renderer renderer{};
+    glm::vec3 cam_target = glm::vec3(0);
+    glm::vec3 cam_pan = glm::vec3(0);
+    float cam_zoom = 0;
+    glm::quat cam_src_rotation = glm::quat(1.0, 0.0, 0.0, 0.0); // identity quaternion
+};
\ No newline at end of file