Added glm. Updated widget to expose mouse focus. Added custom renderer with stippled line.

render.h

@@ -0,0 +1,58 @@
+#pragma once
+
+#include "grbl.h"
+#include "grbl_machine.h"
+#include "glm/ext/matrix_float4x4.hpp"
+#include <nanogui/opengl.h>
+
+namespace grbl {
+
+class shader_program;
+
+class program_renderer {
+public:
+    void update(const program& pgm, const machine& cnc);
+    void render(glm::mat4 mvp, glm::vec2 viewport_size);
+
+    glm::vec3 get_extents_min() const { return min_pos; };
+    glm::vec3 get_extents_max() const { return max_pos; };
+
+private:
+    GLsizei build_vbo(const grbl::program& pgm);
+
+    GLuint vbo_id;
+    GLuint vao_id;
+    shader_program *shader = nullptr;
+    bool initialized = false;
+    glm::vec3 min_pos, max_pos;
+    GLsizei vertices_count;
+};
+
+
+class shader_program {
+public:
+    shader_program(const char *vs_content, const char *ps_content);
+    virtual ~shader_program();
+
+    void bind() const;
+    static void unbind();
+
+    GLuint get_id() const { return program_id; }
+
+    int get_uniform(const char *name);
+
+    void set_mat3(float *value, const char *uniform_name);
+    void set_mat4(float *value, const char *uniform_name);
+    void set_vec2(float *value, const char *uniform_name);
+    void set_vec3(float *value, const char *uniform_name);
+    void set_vec4(float *value, const char *uniform_name);
+    void set_float(float value, const char *uniform_name);
+    void set_int(int value, const char *uniform_name);
+
+private:
+    GLuint program_id;
+    GLuint shader_ids[2];
+    std::map<const char *, int> uniform_cache;
+};
+
+}