commit 708215a2ee86de769af94c55e9ebd8be777ee1e0
Author: Adrian Scripca <benishor@gmail.com>
Date:   Thu Apr 27 14:31:06 2023 +0300

    Initial import

diff --git a/.gitignore b/.gitignore
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--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,3 @@
+.idea
+cmake-build-*
+build/
diff --git a/.gitmodules b/.gitmodules
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+++ b/.gitmodules
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+[submodule "libs/nanogui"]
+	path = libs/nanogui
+	url = https://github.com/mitsuba-renderer/nanogui.git
+[submodule "libs/gtest"]
+	path = libs/gtest
+	url = https://github.com/google/googletest.git
diff --git a/CMakeLists.txt b/CMakeLists.txt
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+++ b/CMakeLists.txt
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+cmake_minimum_required(VERSION 3.13..3.18)
+project(grbl_sender
+        DESCRIPTION "GRBLSender"
+        LANGUAGES CXX C
+        VERSION "1.0"
+        )
+
+# Disable building extras we won't need (pure C++ project)
+set(NANOGUI_BUILD_EXAMPLE OFF CACHE BOOL " " FORCE)
+set(NANOGUI_BUILD_PYTHON OFF CACHE BOOL " " FORCE)
+set(NANOGUI_INSTALL OFF CACHE BOOL " " FORCE)
+
+# Add the configurations from nanogui
+add_subdirectory(libs/nanogui)
+add_subdirectory(libs/gtest)
+include_directories(libs/gtest/googletest/include)
+
+# For reliability of parallel build, make the NanoGUI targets dependencies
+set_property(TARGET glfw glfw_objects nanogui PROPERTY FOLDER "dependencies")
+
+# Use C++17, visibility=hidden by default, interprocedural optimization
+set(CMAKE_CXX_STANDARD 17)
+set(CMAKE_CXX_VISIBILITY_PRESET hidden)
+
+
+add_executable(sender main.cpp grbl.h grbl.cpp grbl_test.cpp)
+target_link_libraries(sender nanogui gtest gtest_main)
\ No newline at end of file
diff --git a/grbl.cpp b/grbl.cpp
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+++ b/grbl.cpp
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+#include "grbl.h"
+
+#include <utility>
+#include <fstream>
+#include <regex>
+#include <iostream>
+
+grbl::instruction grbl::instruction::new_gcode(size_t line, std::string cmd, std::string comment) {
+    return instruction{
+            .line = line,
+            .type = instruction_type::gcode,
+            .command = std::move(cmd),
+            .comment = std::move(comment),
+    };
+}
+
+grbl::instruction grbl::instruction::new_user_message(size_t line, std::string comment) {
+    return instruction{
+            .line = line,
+            .type = instruction_type::user_message,
+            .comment = std::move(comment),
+    };
+}
+
+grbl::instruction grbl::instruction::new_comment(size_t line, std::string comment) {
+    return grbl::instruction{
+            .line = line,
+            .type = instruction_type::comment,
+            .comment = std::move(comment),
+    };
+}
+
+grbl::program::program(std::string filename) {
+    load(std::move(filename));
+}
+
+static auto comment_re = std::regex(R"(\(([^)]*)\))");
+static auto gcode_re = std::regex(R"(([a-zA-Z0-9\s.]+).*(\(([^)]*)\))?)");
+
+bool grbl::program::load(std::istream& in) {
+    is_loaded = true;
+    size_t line_number = 0;
+    for (std::string line; std::getline(in, line);) {
+        line_number++;
+        if (!line.empty()) {
+
+            std::smatch sm{};
+            if (std::regex_match(line, sm, comment_re)) {
+                auto comment = sm.str(1);
+                instructions.emplace_back(instruction::new_comment(line_number, comment));
+            } else if (std::regex_match(line, sm, gcode_re)) {
+                auto command = sm.str(1);
+                auto comment = sm.str(3);
+                instructions.emplace_back(instruction::new_gcode(line_number, command, comment));
+            } else {
+                std::cerr << "Failed to parse line " << line << std::endl;
+                is_loaded = false;
+            }
+        }
+    }
+
+    return is_loaded;
+}
+
+bool grbl::program::load_from_string(const std::string& content) {
+    std::stringstream in_stream;
+    in_stream << content;
+
+    filename = "";
+    is_loaded = load(in_stream);
+    return is_loaded;
+}
+
+bool grbl::program::load(std::string path) {
+    filename = std::move(path);
+    is_loaded = false;
+
+    std::ifstream in_file(filename);
+    if (!in_file) {
+        return false;
+    }
+    is_loaded = load(in_file);
+    return is_loaded;
+}
+
+std::ostream& operator<<(std::ostream& out, const grbl::instruction_type& t) {
+    switch (t) {
+        case grbl::instruction_type::gcode:
+            out << "gcode";
+            break;
+        case grbl::instruction_type::comment:
+            out << "comment";
+            break;
+        case grbl::instruction_type::user_message:
+            out << "user_message";
+            break;
+    }
+    return out;
+}
+
+std::ostream& operator<<(std::ostream& out, const grbl::instruction& i) {
+    out << "{.line: " << i.line << ", .type: " << i.type << ", .cmd: " << i.command << ", .comment: " << i.comment << " }";
+    return out;
+}
+
+void grbl::program::dump(std::ostream& out) {
+    for (auto& i: instructions) {
+        out << i << std::endl;
+    }
+}
diff --git a/grbl.h b/grbl.h
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+++ b/grbl.h
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+#pragma once
+
+#include <string>
+#include <utility>
+#include <vector>
+
+namespace grbl {
+
+enum class instruction_type {
+    gcode,
+    comment,
+    user_message
+};
+
+struct instruction {
+    static instruction new_gcode(size_t line, std::string cmd, std::string comment = "");
+    static instruction new_user_message(size_t line, std::string comment = "");
+    static instruction new_comment(size_t line, std::string comment = "");
+
+    size_t line = 0;
+    instruction_type type = instruction_type::comment;
+    std::string command;
+    std::string comment;
+};
+
+
+
+struct program {
+    program() = default;
+    explicit program(std::string filename);
+
+    bool load(std::string filename);
+    bool load(std::istream& in);
+    bool load_from_string(const std::string& content);
+
+    void dump(std::ostream& out);
+
+    size_t number_of_instructions() const {
+        return instructions.size();
+    }
+
+    instruction instruction_at(size_t index) {
+        return instructions.at(index);
+    }
+
+    bool is_loaded = false;
+    std::string filename;
+    std::vector<instruction> instructions{};
+};
+
+}
diff --git a/grbl_test.cpp b/grbl_test.cpp
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+++ b/grbl_test.cpp
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+#include "grbl.h"
+#include <gtest/gtest.h>
+
+TEST(grbl_program, default_state) {
+    grbl::program pgm;
+
+    EXPECT_EQ("", pgm.filename);
+    EXPECT_EQ(0, pgm.number_of_instructions());
+    EXPECT_EQ(false, pgm.is_loaded);
+}
+
+TEST(grbl_program, load_from_string) {
+    grbl::program pgm;
+
+    std::string content = R"(( pcb2gcode 1.2.2 )
+( Software-independent Gcode )
+
+G94 ( Millimeters per minute feed rate. )
+G21 ( Units == Millimeters. )
+F600.00000
+X3.87739 Y78.52820
+)";
+    pgm.load_from_string(content);
+
+    EXPECT_EQ("", pgm.filename);
+    EXPECT_EQ(6, pgm.number_of_instructions());
+    EXPECT_EQ(true, pgm.is_loaded);
+}
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diff --git a/libs/gtest b/libs/gtest
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+++ b/libs/gtest
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+Subproject commit dea0484e4d3b6a2c50055c24c5617cd662a50c5f
diff --git a/libs/nanogui b/libs/nanogui
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+++ b/libs/nanogui
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+Subproject commit 2ee903c96480d4aee54542ea3c340c13cc06dc32
diff --git a/main.cpp b/main.cpp
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+++ b/main.cpp
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+/*
+    src/example1.cpp -- C++ version of an example application that shows
+    how to use the various widget classes. For a Python implementation, see
+    '../python/example1.py'.
+
+    NanoGUI was developed by Wenzel Jakob <wenzel.jakob@epfl.ch>.
+    The widget drawing code is based on the NanoVG demo application
+    by Mikko Mononen.
+
+    All rights reserved. Use of this source code is governed by a
+    BSD-style license that can be found in the LICENSE.txt file.
+*/
+
+#include <nanogui/opengl.h>
+#include <nanogui/screen.h>
+#include <nanogui/window.h>
+#include <nanogui/layout.h>
+#include <nanogui/label.h>
+#include <nanogui/checkbox.h>
+#include <nanogui/button.h>
+#include <nanogui/toolbutton.h>
+#include <nanogui/popupbutton.h>
+#include <nanogui/combobox.h>
+#include <nanogui/progressbar.h>
+#include <nanogui/icons.h>
+#include <nanogui/messagedialog.h>
+#include <nanogui/textbox.h>
+#include <nanogui/slider.h>
+#include <nanogui/imagepanel.h>
+#include <nanogui/imageview.h>
+#include <nanogui/vscrollpanel.h>
+#include <nanogui/colorwheel.h>
+#include <nanogui/colorpicker.h>
+#include <nanogui/graph.h>
+#include <nanogui/tabwidget.h>
+#include <nanogui/texture.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>
+
+using namespace nanogui;
+
+class SenderApp : public Screen {
+public:
+
+    Window *window;
+    Window *left_window;
+    Window *right_window;
+
+    SenderApp() : Screen(Vector2i(1024, 768), "GRBL Sender") {
+        inc_ref();
+        window = new Window(this, "Button demo");
+//        window->set_fixed_height(Screen::size().y());
+        window->set_position(Vector2i(0, 0));
+        window->set_layout(new GridLayout(nanogui::Orientation::Horizontal, 2, Alignment::Fill, 0, 0));
+        window->set_size(Screen::size());
+
+        left_window = new Window(window, "Left sidebar");
+        left_window->set_modal(true);
+
+        right_window = new Window(window, "Right sidebar");
+        right_window->set_modal(true);
+
+        left_window->set_layout(new GroupLayout());
+
+        // No need to store a pointer, the data structure will be automatically
+        // freed when the parent window is deleted
+        new Label(left_window, "Push buttons", "sans-bold");
+
+        Button *b = new Button(left_window, "Plain button");
+        b->set_callback([] { std::cout << "pushed!" << std::endl; });
+        b->set_tooltip("short tooltip");
+
+        /* Alternative construction notation using variadic template */
+        b = left_window->add<Button>("Styled", FA_ROCKET);
+        b->set_background_color(Color(0, 0, 255, 25));
+        b->set_callback([] { std::cout << "pushed!" << std::endl; });
+        b->set_tooltip("This button has a fairly long tooltip. It is so long, in "
+                       "fact, that the shown text will span several lines.");
+
+        new Label(left_window, "Toggle buttons", "sans-bold");
+        b = new Button(left_window, "Toggle me");
+        b->set_flags(Button::ToggleButton);
+        b->set_change_callback([](bool state) { std::cout << "Toggle button state: " << state << std::endl; });
+
+        new Label(left_window, "Radio buttons", "sans-bold");
+        b = new Button(left_window, "Radio button 1");
+        b->set_flags(Button::RadioButton);
+        b = new Button(left_window, "Radio button 2");
+        b->set_flags(Button::RadioButton);
+
+        new Label(left_window, "A tool palette", "sans-bold");
+        Widget *tools = new Widget(left_window);
+        tools->set_layout(new BoxLayout(Orientation::Horizontal,
+                                        Alignment::Middle, 0, 6));
+
+        b = new ToolButton(tools, FA_CLOUD);
+        b = new ToolButton(tools, FA_FAST_FORWARD);
+        b = new ToolButton(tools, FA_COMPASS);
+        b = new ToolButton(tools, FA_UTENSILS);
+
+        new Label(left_window, "Popup buttons", "sans-bold");
+        PopupButton *popup_btn = new PopupButton(left_window, "Popup", FA_FLASK);
+        Popup *popup = popup_btn->popup();
+        popup->set_layout(new GroupLayout());
+        new Label(popup, "Arbitrary widgets can be placed here");
+        new CheckBox(popup, "A check box");
+        // popup right
+        popup_btn = new PopupButton(popup, "Recursive popup", FA_CHART_PIE);
+        Popup *popup_right = popup_btn->popup();
+        popup_right->set_layout(new GroupLayout());
+        new CheckBox(popup_right, "Another check box");
+        // popup left
+        popup_btn = new PopupButton(popup, "Recursive popup", FA_DNA);
+        popup_btn->set_side(Popup::Side::Left);
+        Popup *popup_left = popup_btn->popup();
+        popup_left->set_layout(new GroupLayout());
+        new CheckBox(popup_left, "Another check box");
+
+        /*
+        window = new Window(this, "Basic widgets");
+        window->set_position(Vector2i(200, 15));
+        window->set_layout(new GroupLayout());
+
+        new Label(window, "Message dialog", "sans-bold");
+        tools = new Widget(window);
+        tools->set_layout(new BoxLayout(Orientation::Horizontal,
+                                        Alignment::Middle, 0, 6));
+        b = new Button(tools, "Info");
+        b->set_callback([&] {
+            auto dlg = new MessageDialog(this, MessageDialog::Type::Information, "Title", "This is an information message");
+            dlg->set_callback([](int result) { std::cout << "Dialog result: " << result << std::endl; });
+        });
+        b = new Button(tools, "Warn");
+        b->set_callback([&] {
+            auto dlg = new MessageDialog(this, MessageDialog::Type::Warning, "Title", "This is a warning message");
+            dlg->set_callback([](int result) { std::cout << "Dialog result: " << result << std::endl; });
+        });
+        b = new Button(tools, "Ask");
+        b->set_callback([&] {
+            auto dlg = new MessageDialog(this, MessageDialog::Type::Question, "Title", "This is a question message", "Yes", "No", true);
+            dlg->set_callback([](int result) { std::cout << "Dialog result: " << result << std::endl; });
+        });
+
+#if defined(_WIN32)
+        /// Executable is in the Debug/Release/.. subdirectory
+        std::string resources_folder_path("../icons");
+#else
+        std::string resources_folder_path("./icons");
+#endif
+        std::vector<std::pair<int, std::string>> icons;
+
+#if !defined(EMSCRIPTEN)
+        try {
+            icons = load_image_directory(m_nvg_context, resources_folder_path);
+        } catch (const std::exception& e) {
+            std::cerr << "Warning: " << e.what() << std::endl;
+        }
+#endif
+
+        new Label(window, "Image panel & scroll panel", "sans-bold");
+        PopupButton *image_panel_btn = new PopupButton(window, "Image Panel");
+        image_panel_btn->set_icon(FA_IMAGES);
+        popup = image_panel_btn->popup();
+        VScrollPanel *vscroll = new VScrollPanel(popup);
+        ImagePanel *img_panel = new ImagePanel(vscroll);
+        img_panel->set_images(icons);
+        popup->set_fixed_size(Vector2i(245, 150));
+
+        auto image_window = new Window(this, "Selected image");
+        image_window->set_position(Vector2i(710, 15));
+        image_window->set_layout(new GroupLayout(3));
+
+        // Create a Texture instance for each object
+        for (auto& icon: icons) {
+            Vector2i size;
+            int n = 0;
+            ImageHolder texture_data(
+                    stbi_load((icon.second + ".png").c_str(), &size.x(), &size.y(), &n, 0),
+                    stbi_image_free);
+            assert(n == 4);
+
+            Texture *tex = new Texture(
+                    Texture::PixelFormat::RGBA,
+                    Texture::ComponentFormat::UInt8,
+                    size,
+                    Texture::InterpolationMode::Trilinear,
+                    Texture::InterpolationMode::Nearest);
+
+            tex->upload(texture_data.get());
+
+            m_images.emplace_back(tex, std::move(texture_data));
+        }
+
+        ImageView *image_view = new ImageView(image_window);
+        if (!m_images.empty())
+            image_view->set_image(m_images[0].first);
+        image_view->center();
+        m_current_image = 0;
+
+        img_panel->set_callback([this, image_view](int i) {
+            std::cout << "Selected item " << i << std::endl;
+            image_view->set_image(m_images[i].first);
+            m_current_image = i;
+        });
+
+        image_view->set_pixel_callback(
+                [this](const Vector2i& index, char **out, size_t size) {
+                    const Texture *texture = m_images[m_current_image].first.get();
+                    uint8_t *data = m_images[m_current_image].second.get();
+                    for (int ch = 0; ch < 4; ++ch) {
+                        uint8_t value = data[(index.x() + index.y() * texture->size().x()) * 4 + ch];
+                        snprintf(out[ch], size, "%i", (int) value);
+                    }
+                }
+        );
+
+        new Label(window, "File dialog", "sans-bold");
+        tools = new Widget(window);
+        tools->set_layout(new BoxLayout(Orientation::Horizontal,
+                                        Alignment::Middle, 0, 6));
+        b = new Button(tools, "Open");
+        b->set_callback([&] {
+            std::cout << "File dialog result: " << file_dialog(
+                    {{"png", "Portable Network Graphics"},
+                     {"txt", "Text file"}}, false) << std::endl;
+        });
+        b = new Button(tools, "Save");
+        b->set_callback([&] {
+            std::cout << "File dialog result: " << file_dialog(
+                    {{"png", "Portable Network Graphics"},
+                     {"txt", "Text file"}}, true) << std::endl;
+        });
+
+        new Label(window, "Combo box", "sans-bold");
+        new ComboBox(window, {"Combo box item 1", "Combo box item 2", "Combo box item 3"});
+        new Label(window, "Check box", "sans-bold");
+        CheckBox *cb = new CheckBox(window, "Flag 1",
+                                    [](bool state) { std::cout << "Check box 1 state: " << state << std::endl; }
+        );
+        cb->set_checked(true);
+        cb = new CheckBox(window, "Flag 2",
+                          [](bool state) { std::cout << "Check box 2 state: " << state << std::endl; }
+        );
+        new Label(window, "Progress bar", "sans-bold");
+        m_progress = new ProgressBar(window);
+
+        new Label(window, "Slider and text box", "sans-bold");
+
+        Widget *panel = new Widget(window);
+        panel->set_layout(new BoxLayout(Orientation::Horizontal,
+                                        Alignment::Middle, 0, 20));
+
+        Slider *slider = new Slider(panel);
+        slider->set_value(0.5f);
+        slider->set_fixed_width(80);
+
+        TextBox *text_box = new TextBox(panel);
+        text_box->set_fixed_size(Vector2i(60, 25));
+        text_box->set_value("50");
+        text_box->set_units("%");
+        slider->set_callback([text_box](float value) {
+            text_box->set_value(std::to_string((int) (value * 100)));
+        });
+        slider->set_final_callback([&](float value) {
+            std::cout << "Final slider value: " << (int) (value * 100) << std::endl;
+        });
+        text_box->set_fixed_size(Vector2i(60, 25));
+        text_box->set_font_size(20);
+        text_box->set_alignment(TextBox::Alignment::Right);
+
+        window = new Window(this, "Misc. widgets");
+        window->set_position(Vector2i(425, 15));
+        window->set_layout(new GroupLayout());
+
+        TabWidget *tab_widget = window->add<TabWidget>();
+
+        Widget *layer = new Widget(tab_widget);
+        layer->set_layout(new GroupLayout());
+        tab_widget->append_tab("Color Wheel", layer);
+
+        // Use overloaded variadic add to fill the tab widget with Different tabs.
+        layer->add<Label>("Color wheel widget", "sans-bold");
+        layer->add<ColorWheel>();
+
+        layer = new Widget(tab_widget);
+        layer->set_layout(new GroupLayout());
+        tab_widget->append_tab("Function Graph", layer);
+
+        layer->add<Label>("Function graph widget", "sans-bold");
+
+        Graph *graph = layer->add<Graph>("Some Function");
+
+        graph->set_header("E = 2.35e-3");
+        graph->set_footer("Iteration 89");
+        std::vector<float>& func = graph->values();
+        func.resize(100);
+        for (int i = 0; i < 100; ++i)
+            func[i] = 0.5f * (0.5f * std::sin(i / 10.f) +
+                              0.5f * std::cos(i / 23.f) + 1);
+
+        // Dummy tab used to represent the last tab button.
+        int plus_id = tab_widget->append_tab("+", new Widget(tab_widget));
+
+        // A simple counter.
+        int counter = 1;
+        tab_widget->set_callback([tab_widget, this, counter, plus_id](int id) mutable {
+            if (id == plus_id) {
+                // When the "+" tab has been clicked, simply add a new tab.
+                std::string tab_name = "Dynamic " + std::to_string(counter);
+                Widget *layer_dyn = new Widget(tab_widget);
+                int new_id = tab_widget->insert_tab(tab_widget->tab_count() - 1,
+                                                    tab_name, layer_dyn);
+                layer_dyn->set_layout(new GroupLayout());
+                layer_dyn->add<Label>("Function graph widget", "sans-bold");
+                Graph *graph_dyn = layer_dyn->add<Graph>("Dynamic function");
+
+                graph_dyn->set_header("E = 2.35e-3");
+                graph_dyn->set_footer("Iteration " + std::to_string(new_id * counter));
+                std::vector<float>& func_dyn = graph_dyn->values();
+                func_dyn.resize(100);
+                for (int i = 0; i < 100; ++i)
+                    func_dyn[i] = 0.5f *
+                                  std::abs((0.5f * std::sin(i / 10.f + counter) +
+                                            0.5f * std::cos(i / 23.f + 1 + counter)));
+                ++counter;
+                tab_widget->set_selected_id(new_id);
+
+                // We must invoke the layout manager after adding tabs dynamically
+                perform_layout();
+            }
+        });
+
+        // A button to go back to the first tab and scroll the window.
+        panel = window->add<Widget>();
+        panel->add<Label>("Jump to tab: ");
+        panel->set_layout(new BoxLayout(Orientation::Horizontal,
+                                        Alignment::Middle, 0, 6));
+
+        auto ib = panel->add<IntBox<int>>();
+        ib->set_editable(true);
+
+        b = panel->add<Button>("", FA_FORWARD);
+        b->set_fixed_size(Vector2i(22, 22));
+        ib->set_fixed_height(22);
+        b->set_callback([tab_widget, ib] {
+            int value = ib->value();
+            if (value >= 0 && value < tab_widget->tab_count())
+                tab_widget->set_selected_index(value);
+        });
+
+        window = new Window(this, "Grid of small widgets");
+        window->set_position(Vector2i(425, 300));
+        GridLayout *layout =
+                new GridLayout(Orientation::Horizontal, 2,
+                               Alignment::Middle, 15, 5);
+        layout->set_col_alignment(
+                {Alignment::Maximum, Alignment::Fill});
+        layout->set_spacing(0, 10);
+        window->set_layout(layout);
+
+        // FP widget
+        {
+            new Label(window, "Floating point :", "sans-bold");
+            text_box = new TextBox(window);
+            text_box->set_editable(true);
+            text_box->set_fixed_size(Vector2i(100, 20));
+            text_box->set_value("50");
+            text_box->set_units("GiB");
+            text_box->set_default_value("0.0");
+            text_box->set_font_size(16);
+            text_box->set_format("[-]?[0-9]*\\.?[0-9]+");
+        }
+
+        // Positive integer widget
+         {
+            new Label(window, "Positive integer :", "sans-bold");
+            auto int_box = new IntBox<int>(window);
+            int_box->set_editable(true);
+            int_box->set_fixed_size(Vector2i(100, 20));
+            int_box->set_value(50);
+            int_box->set_units("Mhz");
+            int_box->set_default_value("0");
+            int_box->set_font_size(16);
+            int_box->set_format("[1-9][0-9]*");
+            int_box->set_spinnable(true);
+            int_box->set_min_value(1);
+            int_box->set_value_increment(2);
+        }
+
+        // Checkbox widget
+         {
+            new Label(window, "Checkbox :", "sans-bold");
+
+            cb = new CheckBox(window, "Check me");
+            cb->set_font_size(16);
+            cb->set_checked(true);
+        }
+
+        new Label(window, "Combo box :", "sans-bold");
+        ComboBox *cobo =
+                new ComboBox(window, {"Item 1", "Item 2", "Item 3"});
+        cobo->set_font_size(16);
+        cobo->set_fixed_size(Vector2i(100, 20));
+
+        new Label(window, "Color picker :", "sans-bold");
+        auto cp = new ColorPicker(window, {255, 120, 0, 255});
+        cp->set_fixed_size({100, 20});
+        cp->set_final_callback([](const Color& c) {
+            std::cout << "ColorPicker final callback: ["
+                      << c.r() << ", "
+                      << c.g() << ", "
+                      << c.b() << ", "
+                      << c.w() << "]" << std::endl;
+        });
+        // setup a fast callback for the color picker widget on a new window
+        // for demonstrative purposes
+        window = new Window(this, "Color Picker Fast Callback");
+        layout = new GridLayout(Orientation::Horizontal, 2,
+                                Alignment::Middle, 15, 5);
+        layout->set_col_alignment(
+                {Alignment::Maximum, Alignment::Fill});
+        layout->set_spacing(0, 10);
+        window->set_layout(layout);
+        window->set_position(Vector2i(425, 500));
+        new Label(window, "Combined: ");
+        b = new Button(window, "ColorWheel", FA_INFINITY);
+        new Label(window, "Red: ");
+        auto red_int_box = new IntBox<int>(window);
+        red_int_box->set_editable(false);
+        new Label(window, "Green: ");
+        auto green_int_box = new IntBox<int>(window);
+        green_int_box->set_editable(false);
+        new Label(window, "Blue: ");
+        auto blue_int_box = new IntBox<int>(window);
+        blue_int_box->set_editable(false);
+        new Label(window, "Alpha: ");
+        auto alpha_int_box = new IntBox<int>(window);
+
+        cp->set_callback([b, red_int_box, blue_int_box, green_int_box, alpha_int_box](const Color& c) {
+            b->set_background_color(c);
+            b->set_text_color(c.contrasting_color());
+            int red = (int) (c.r() * 255.0f);
+            red_int_box->set_value(red);
+            int green = (int) (c.g() * 255.0f);
+            green_int_box->set_value(green);
+            int blue = (int) (c.b() * 255.0f);
+            blue_int_box->set_value(blue);
+            int alpha = (int) (c.w() * 255.0f);
+            alpha_int_box->set_value(alpha);
+        });
+         */
+
+        perform_layout();
+
+//           All NanoGUI widgets are initialized at this point. Now
+//           create shaders to draw the main window contents.
+//
+//           NanoGUI comes with a simple wrapper around OpenGL 3, which
+//           eliminates most of the tedious and error-prone shader and buffer
+//           object management.
+
+        m_render_pass = new RenderPass({this});
+        m_render_pass->set_clear_color(0, Color(0.3f, 0.3f, 0.32f, 1.f));
+
+        m_shader = new Shader(
+                m_render_pass,
+
+                /* An identifying name */
+                "a_simple_shader",
+
+#if defined(NANOGUI_USE_OPENGL)
+                R"(/* Vertex shader */
+            #version 330
+            uniform mat4 mvp;
+            in vec3 position;
+            void main() {
+                gl_Position = mvp * vec4(position, 1.0);
+            })",
+
+                /* Fragment shader */
+                R"(#version 330
+            out vec4 color;
+            uniform float intensity;
+            void main() {
+                color = vec4(vec3(intensity), 1.0);
+            })"
+#elif defined(NANOGUI_USE_GLES)
+                R"(/* Vertex shader */
+            precision highp float;
+            uniform mat4 mvp;
+            attribute vec3 position;
+            void main() {
+                gl_Position = mvp * vec4(position, 1.0);
+            })",
+
+                /* Fragment shader */
+                R"(precision highp float;
+            uniform float intensity;
+            void main() {
+                gl_FragColor = vec4(vec3(intensity), 1.0);
+            })"
+#elif defined(NANOGUI_USE_METAL)
+                R"(using namespace metal;
+            struct VertexOut {
+                float4 position [[position]];
+            };
+
+            vertex VertexOut vertex_main(const device packed_float3 *position,
+                                         constant float4x4 &mvp,
+                                         uint id [[vertex_id]]) {
+                VertexOut vert;
+                vert.position = mvp * float4(position[id], 1.f);
+                return vert;
+            })",
+
+                /* Fragment shader */
+                R"(using namespace metal;
+            fragment float4 fragment_main(const constant float &intensity) {
+                return float4(intensity);
+            })"
+#endif
+        );
+
+        uint32_t indices[3 * 2] = {
+                0, 1, 2,
+                2, 3, 0
+        };
+
+        float positions[3 * 4] = {
+                -1.f, -1.f, 0.f,
+                1.f, -1.f, 0.f,
+                1.f, 1.f, 0.f,
+                -1.f, 1.f, 0.f
+        };
+
+        m_shader->set_buffer("indices", VariableType::UInt32, {3 * 2}, indices);
+        m_shader->set_buffer("position", VariableType::Float32, {4, 3}, positions);
+        m_shader->set_uniform("intensity", 0.5f);
+    }
+
+    bool resize_event(const Vector2i& size) override {
+        window->set_size(size);
+        Screen::resize_event(size);
+        return true;
+    }
+
+    virtual bool 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_UP) {
+            if (action == GLFW_PRESS) {
+                set_caption("Jogging");
+            } else if (action == GLFW_RELEASE) {
+                set_caption("Idle");
+            }
+        }
+        return false;
+    }
+
+    virtual void draw(NVGcontext *ctx) {
+        // Animate the scrollbar
+//        m_progress->set_value(std::fmod((float) glfwGetTime() / 10, 1.0f));
+
+        // Draw the user interface
+        Screen::draw(ctx);
+    }
+
+    virtual void draw_contents() {
+        Matrix4f mvp = Matrix4f::scale(Vector3f(
+                (float) m_size.y() / (float) m_size.x() * 0.25f, 0.25f, 0.25f)) *
+                       Matrix4f::rotate(Vector3f(0, 0, 1), (float) glfwGetTime());
+
+        m_shader->set_uniform("mvp", mvp);
+
+        m_render_pass->resize(framebuffer_size());
+        m_render_pass->begin();
+
+        m_shader->begin();
+        m_shader->draw_array(Shader::PrimitiveType::Triangle, 0, 6, true);
+        m_shader->end();
+
+        m_render_pass->end();
+    }
+
+private:
+    ProgressBar *m_progress;
+    ref<Shader> m_shader;
+    ref<RenderPass> m_render_pass;
+
+    using ImageHolder = std::unique_ptr<uint8_t[], void (*)(void *)>;
+    std::vector<std::pair<ref<Texture>, ImageHolder>> m_images;
+    int m_current_image;
+};
+
+int main(int argc, char **argv) {
+
+    testing::InitGoogleTest(&argc, argv);
+    auto result = RUN_ALL_TESTS();
+    if (result) {
+        exit(result);
+    }
+
+    try {
+
+        grbl::program pgm;
+        pgm.load("./program.nc");
+        pgm.dump(std::cout);
+
+        nanogui::init();
+
+        // scoped variables
+        {
+            ref<SenderApp> app = new SenderApp();
+            app->dec_ref();
+            app->draw_all();
+            app->set_visible(true);
+            nanogui::mainloop(1 / 60.f * 1000);
+        }
+
+        nanogui::shutdown();
+    } 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;
+    } catch (...) {
+        std::cerr << "Caught an unknown error!" << std::endl;
+        return -2;
+    }
+
+    return 0;
+}
diff --git a/resources/FontAwesome-Solid.ttf b/resources/FontAwesome-Solid.ttf
new file mode 100644
index 0000000..5a6d747
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diff --git a/resources/Inconsolata-Regular.ttf b/resources/Inconsolata-Regular.ttf
new file mode 100644
index 0000000..592ccd2
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diff --git a/resources/Roboto-Bold.ttf b/resources/Roboto-Bold.ttf
new file mode 100644
index 0000000..aaf374d
Binary files /dev/null and b/resources/Roboto-Bold.ttf differ
diff --git a/resources/Roboto-Regular.ttf b/resources/Roboto-Regular.ttf
new file mode 100644
index 0000000..3e6e2e7
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diff --git a/resources/bin2c.cmake b/resources/bin2c.cmake
new file mode 100644
index 0000000..97884ef
--- /dev/null
+++ b/resources/bin2c.cmake
@@ -0,0 +1,31 @@
+cmake_minimum_required (VERSION 2.8.12)
+
+# Create header for C file
+file(WRITE ${OUTPUT_C} "/* Autogenerated by bin2c */\n\n")
+file(APPEND ${OUTPUT_C} "#include <stdint.h>\n\n")
+
+# Create header of H file
+file(WRITE ${OUTPUT_H} "/* Autogenerated by bin2c */\n\n")
+file(APPEND ${OUTPUT_H} "#pragma once\n")
+file(APPEND ${OUTPUT_H} "#include <stdint.h>\n\n")
+
+string(REPLACE "," ";" INPUT_LIST ${INPUT_FILES})
+
+
+# Iterate through binary files files
+foreach(bin ${INPUT_LIST})
+  # Get short filename
+  string(REGEX MATCH "([^/]+)$" filename ${bin})
+  # Replace filename spaces & extension separator for C compatibility
+  string(REGEX REPLACE "\\.| |-" "_" filename ${filename})
+  # Convert to lower case
+  string(TOLOWER ${filename} filename)
+  # Read hex data from file
+  file(READ ${bin} filedata HEX)
+  # Convert hex data for C compatibility
+  string(REGEX REPLACE "([0-9a-f][0-9a-f])" "0x\\1," filedata "${filedata}")
+  # Append data to c file
+  file(APPEND ${OUTPUT_C} "extern const uint8_t ${filename}[] = {${filedata}0x00};\n\nuint32_t ${filename}_size = sizeof(${filename}) - 1;\n\n")
+  # Append extern definitions to h file
+  file(APPEND ${OUTPUT_H} "extern const uint8_t ${filename}[];\n\nextern uint32_t ${filename}_size;\n\n")
+endforeach()
diff --git a/resources/check-style.sh b/resources/check-style.sh
new file mode 100755
index 0000000..70a1b92
--- /dev/null
+++ b/resources/check-style.sh
@@ -0,0 +1,83 @@
+#!/bin/bash
+#
+# Script to check include/test code for common pybind11 code style errors.
+#
+# This script currently checks for
+#
+# 1. use of tabs instead of spaces
+# 2. MSDOS-style CRLF endings
+# 3. trailing spaces
+# 4. missing space between keyword and parenthesis, e.g.: for(, if(, while(
+# 5. Missing space between right parenthesis and brace, e.g. 'for (...){'
+# 6. opening brace on its own line. It should always be on the same line as the
+#    if/while/for/do statment.
+#
+# Invoke as: tools/check-style.sh
+#
+
+errors=0
+IFS=$'\n'
+found=
+# The mt=41 sets a red background for matched tabs:
+exec 3< <(GREP_COLORS='mt=41' grep $'\t' include/ src/ python/*.{h,cpp} docs/*.rst -rn --color=always)
+while read -u 3 f; do
+    if [ -z "$found" ]; then
+        echo -e '\e[31m\e[01mError: found tabs instead of spaces in the following files:\e[0m'
+        found=1
+        errors=1
+    fi
+
+    echo "    $f"
+done
+
+found=
+# The mt=41 sets a red background for matched MS-DOS CRLF characters
+exec 3< <(GREP_COLORS='mt=41' grep -IUlr $'\r' include/ src/ python/*.{h,cpp} docs/*.rst --color=always)
+while read -u 3 f; do
+    if [ -z "$found" ]; then
+        echo -e '\e[31m\e[01mError: found CRLF characters in the following files:\e[0m'
+        found=1
+        errors=1
+    fi
+
+    echo "    $f"
+done
+
+found=
+# The mt=41 sets a red background for matched trailing spaces
+exec 3< <(GREP_COLORS='mt=41' grep '\s\+$' include/ src/ python/*.{h,cpp} docs/*.rst -rn --color=always)
+while read -u 3 f; do
+    if [ -z "$found" ]; then
+        echo -e '\e[31m\e[01mError: found trailing spaces in the following files:\e[0m'
+        found=1
+        errors=1
+    fi
+
+    echo "    $f"
+done
+
+found=
+exec 3< <(grep '\<\(if\|for\|while\|catch\)(\|){' include/ src/ python/*.{h,cpp} -rn --color=always)
+while read -u 3 line; do
+    if [ -z "$found" ]; then
+        echo -e '\e[31m\e[01mError: found the following coding style problems:\e[0m'
+        found=1
+        errors=1
+    fi
+
+    echo "    $line"
+done
+
+found=
+exec 3< <(GREP_COLORS='mt=41' grep '^\s*{\s*$' include/ src/ -rn --color=always)
+while read -u 3 f; do
+    if [ -z "$found" ]; then
+        echo -e '\e[31m\e[01mError: braces should occur on the same line as the if/while/.. statement. Found issues in the following files: \e[0m'
+        found=1
+        errors=1
+    fi
+
+    echo "    $f"
+done
+
+exit $errors
diff --git a/resources/fa-import.py b/resources/fa-import.py
new file mode 100644
index 0000000..d96ed67
--- /dev/null
+++ b/resources/fa-import.py
@@ -0,0 +1,132 @@
+# Imports FontAwesome's 'all.css' and creates the 'icons.h' header file
+
+import yaml
+
+with open("icons.yml", 'r') as stream:
+    try:
+        data = yaml.safe_load(stream)
+    except yaml.YAMLError as exc:
+        print(exc)
+
+icons = []
+for key, value in data.items():
+    if 'solid' in value['styles']:
+        key = 'fa-' + key
+        name = key.replace('-', '_').upper()
+        spacer = " " * (40-len(name))
+        icons.append((key, name, spacer, value['unicode']))
+
+
+with open("icons.h", 'w') as f:
+    f.write('''/*
+    NanoGUI was developed by Wenzel Jakob <wenzel.jakob@epfl.ch>.
+    The widget drawing code is based on the NanoVG demo application
+    by Mikko Mononen.
+
+    All rights reserved. Use of this source code is governed by a
+    BSD-style license that can be found in the LICENSE.txt file.
+*/
+
+/* Developer note: need to make a change to this file?
+ * Please raise an Issue on GitHub describing what needs to change.  This file
+ * was generated, so the scripts that generated it needs to update as well.
+ */
+
+/**
+ * \\file nanogui/icons.h
+ *
+ * \\brief This is a list of icon codes for the free variant of the
+ * FontAwesome 5.10.1 font.
+ *
+ * \\rst
+ *
+ * This file defines the full listing of
+ * `FontAwesome <https://raw.githubusercontent.com/FortAwesome/Font-Awesome>`_
+ * icons available in NanoGUI.  Please note that if viewing the documentation
+ * on the web, your browser may display the icons differently than what they
+ * look like in NanoGUI.  Run the one of the :ref:`nanogui_example_icons`
+ * executables to see what they all look like in NanoGUI.
+ *
+ * .. tip::
+ *
+ *    In C++, ``#include <nanogui/icons.h>`` to gain access to the ``#define``
+ *    shown in these docs and simply reference the names as listed in the
+ *    documentation.  To use the icons from Python, declare
+ *    ``from nanogui import icons`` and reference the icons as follows:
+ *    ``icons.FA_ASTERISK``.
+ *
+ * The following icons are available:
+ *
+ * .. raw:: html
+ *
+ *    <center>
+ *      <div class="wy-table-responsive">
+ *        <table class="docutils" border=1>
+ *          <colgroup>
+ *            <col width="90%" align="center"/>
+ *            <col width="10%" align="center" />
+ *          </colgroup>
+ *          <thead valign="bottom">
+ *            <tr class="row-odd">
+ *              <th class="head" align="center">Definition</th>
+ *              <th class="head" align="center">Icon</th>
+ *            </tr>
+ *          </thead>
+ *          <tbody valign="top">
+''')
+
+    for i, icon in enumerate(icons):
+        evenodd = 'even' if i % 2 == 0 else 'odd'
+        name_orig = icon[0]
+        name_new = icon[1]
+        f.write(f''' *            <tr class="row-{evenodd}">
+ *              <td align="right"><code>{name_new}</code></td>
+ *              <td align="center"><span class="{name_orig}"></span></td>
+ *            </tr>
+''')
+    f.write(''' *          </tbody>
+ *        </table>
+ *      </div><!-- wy-table-responsive -->
+ *    </center>
+ *
+ * \endrst
+ */
+
+#pragma once
+
+// prevent individual pages from being generated for all of these
+#if !defined(DOXYGEN_SHOULD_SKIP_THIS)
+
+''')
+    for name_orig, name_new, spacer, hexcode in icons:
+        f.write(f'#define {name_new}{spacer}0x{hexcode}\n')
+    f.write('\n#endif // DOXYGEN_SHOULD_SKIP_THIS\n')
+
+
+with open('icons.cpp', 'w') as f:
+    f.write('''#ifdef NANOGUI_PYTHON
+
+#include "python.h"
+
+/* Developer note: need to make a change to this file?
+ * Please raise an Issue on GitHub describing what needs to change.  This file
+ * was generated, so the scripts that generated it needs to update as well.
+ */
+
+void register_entypo(py::module &m) {
+    /* Entypo constants */
+    {
+        #define C(name) g.attr(#name) = py::int_(name);
+        py::module g = m.def_submodule("icons");
+''')
+    for name_orig, name_new, spacer, hexcode in icons:
+        f.write(f'        C({name_new});\n')
+    f.write('''        #undef C
+    }
+}
+
+#endif
+''')
+with open('example_icons.cpp', 'w') as f:
+    for name_orig, name_new, spacer, hexcode in icons:
+        f.write(f'        ADD_BUTTON({name_new});\n')
diff --git a/resources/icons/icon1.png b/resources/icons/icon1.png
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diff --git a/resources/icons/icon3.png b/resources/icons/icon3.png
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diff --git a/resources/icons/icon6.ico b/resources/icons/icon6.ico
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diff --git a/resources/icons/icon6.png b/resources/icons/icon6.png
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diff --git a/resources/icons/icon7.png b/resources/icons/icon7.png
new file mode 100644
index 0000000..ca05f06
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diff --git a/resources/icons/icon8.png b/resources/icons/icon8.png
new file mode 100644
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diff --git a/resources/imageview_fragment.gl b/resources/imageview_fragment.gl
new file mode 100644
index 0000000..174f377
--- /dev/null
+++ b/resources/imageview_fragment.gl
@@ -0,0 +1,18 @@
+#version 330
+
+in vec2 uv;
+in vec2 position_background;
+out vec4 frag_color;
+uniform sampler2D image;
+uniform vec4 background_color;
+
+void main() {
+    vec2 frac = position_background - floor(position_background);
+    float checkerboard = ((frac.x > .5) == (frac.y > .5)) ? 0.4 : 0.5;
+
+    vec4 background = (1.0 - background_color.a) * vec4(vec3(checkerboard), 1.0) +
+                              background_color.a * vec4(background_color.rgb, 1.0);
+
+    vec4 value = texture(image, uv);
+    frag_color = (1.0 - value.a) * background + value.a * vec4(value.rgb, 1.0);
+}
diff --git a/resources/imageview_fragment.gles b/resources/imageview_fragment.gles
new file mode 100644
index 0000000..549d81b
--- /dev/null
+++ b/resources/imageview_fragment.gles
@@ -0,0 +1,17 @@
+precision highp float;
+
+varying vec2 uv;
+varying vec2 position_background;
+uniform sampler2D image;
+uniform vec4 background_color;
+
+void main() {
+    vec2 frac = position_background - floor(position_background);
+    float checkerboard = ((frac.x > .5) == (frac.y > .5)) ? 0.4 : 0.5;
+
+    vec4 background = (1.0 - background_color.a) * vec4(vec3(checkerboard), 1.0) +
+                             background_color.a * vec4(background_color.rgb, 1.0);
+
+    vec4 value = texture2D(image, uv);
+    gl_FragColor = (1.0 - value.a) * background + value.a * vec4(value.rgb, 1.0);
+}
diff --git a/resources/imageview_fragment.metal b/resources/imageview_fragment.metal
new file mode 100644
index 0000000..ead8932
--- /dev/null
+++ b/resources/imageview_fragment.metal
@@ -0,0 +1,23 @@
+#include <metal_stdlib>
+
+using namespace metal;
+
+struct VertexOut {
+    float4 position_image [[position]];
+    float2 position_background;
+    float2 uv;
+};
+
+fragment float4 fragment_main(VertexOut vert [[stage_in]],
+                              texture2d<float, access::sample> image,
+                              constant float4 &background_color,
+                              sampler image_sampler) {
+    float2 frac = vert.position_background - floor(vert.position_background);
+    float checkerboard = ((frac.x > .5f) == (frac.y > .5f)) ? .4f : .5f;
+
+    float4 background = (1.f - background_color.a) * float4(float3(checkerboard), 1.f) +
+                                background_color.a * float4(background_color.rgb, 1.f);
+
+    float4 value = image.sample(image_sampler, vert.uv);
+    return (1.f - value.a) * background + value.a * float4(value.rgb, 1.f);
+}
diff --git a/resources/imageview_vertex.gl b/resources/imageview_vertex.gl
new file mode 100644
index 0000000..559d111
--- /dev/null
+++ b/resources/imageview_vertex.gl
@@ -0,0 +1,14 @@
+#version 330
+
+uniform mat4 matrix_image;
+uniform mat4 matrix_background;
+in vec2 position;
+out vec2 position_background;
+out vec2 uv;
+
+void main() {
+    vec4 p = vec4(position, 0.0, 1.0);
+    gl_Position = matrix_image * p;
+    position_background = (matrix_background * p).xy;
+    uv = position;
+}
diff --git a/resources/imageview_vertex.gles b/resources/imageview_vertex.gles
new file mode 100644
index 0000000..582b822
--- /dev/null
+++ b/resources/imageview_vertex.gles
@@ -0,0 +1,14 @@
+precision highp float;
+
+uniform mat4 matrix_image;
+uniform mat4 matrix_background;
+attribute vec2 position;
+varying vec2 position_background;
+varying vec2 uv;
+
+void main() {
+    vec4 p = vec4(position, 0.0, 1.0);
+    gl_Position = matrix_image * p;
+    position_background = (matrix_background * p).xy;
+    uv = position;
+}
diff --git a/resources/imageview_vertex.metal b/resources/imageview_vertex.metal
new file mode 100644
index 0000000..c6b44f7
--- /dev/null
+++ b/resources/imageview_vertex.metal
@@ -0,0 +1,21 @@
+#include <metal_stdlib>
+
+using namespace metal;
+
+struct VertexOut {
+    float4 position_image [[position]];
+    float2 position_background;
+    float2 uv;
+};
+
+vertex VertexOut vertex_main(const device float2 *position,
+                             constant float4x4 &matrix_image,
+                             constant float4x4 &matrix_background,
+                             uint id [[vertex_id]]) {
+    float4 p = float4(position[id], 0.f, 1.f);
+    VertexOut vert;
+    vert.position_image = matrix_image * p;
+    vert.position_background = (matrix_background * p).xy;
+    vert.uv = p.xy;
+    return vert;
+}
diff --git a/resources/nanoguiConfig.cmake.in b/resources/nanoguiConfig.cmake.in
new file mode 100644
index 0000000..de51702
--- /dev/null
+++ b/resources/nanoguiConfig.cmake.in
@@ -0,0 +1,14 @@
+@PACKAGE_INIT@
+
+set(nanogui_INCLUDE_DIR "${PACKAGE_PREFIX_DIR}/@CMAKE_INSTALL_INCLUDEDIR@")
+set(nanogui_VERSION_TYPE "@ENOKI_VERSION_TYPE@")
+set(nanogui_LIBRARY "")
+
+check_required_components(nanogui)
+
+include("${CMAKE_CURRENT_LIST_DIR}/nanoguiTargets.cmake")
+
+if(NOT nanogui_FIND_QUIETLY)
+  message(STATUS "Found nanogui: ${nanogui_INCLUDE_DIR} (found version \"${nanogui_VERSION}\" ${nanogui_VERSION_TYPE})")
+endif()
+
diff --git a/resources/screenshot.png b/resources/screenshot.png
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diff --git a/resources/screenshot2.png b/resources/screenshot2.png
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