chuwilliamson · September 13, 2018 19:14
diff --git a/imgui_impl_glfw_gl3.cpp b/imgui_impl_glfw_gl3.cpp
 // ImGui GLFW binding with OpenGL3 + shaders
 // You can copy and use unmodified imgui_impl_* files in your project. See main.cpp for an example of using this.
 // If you use this binding you'll need to call 4 functions: ImGui_ImplXXXX_Init(), ImGui_ImplXXXX_NewFrame(), ImGui::Render() and ImGui_ImplXXXX_Shutdown().
 // If you are new to ImGui, see examples/README.txt and documentation at the top of imgui.cpp.
 // https://github.com/ocornut/imgui

 #include <imgui.h>
 #include "imgui_impl_glfw_gl3.h"

 // GL_CORE/GLFW
 #include "gl_core_4_4.h"
 #include <GLFW\glfw3.h>

 #ifdef _WIN32
 #undef APIENTRY
 #define GLFW_EXPOSE_NATIVE_WIN32
 #define GLFW_EXPOSE_NATIVE_WGL
 #include <GLFW\glfw3native.h>
 #endif

 // Data
 namespace imgui_impl {
 	static GLFWwindow*  g_Window = nullptr;
 	static double       g_Time = 0.0f;
 	static bool         g_MousePressed[3] = { false, false, false };
 	static float        g_MouseWheel = 0.0f;
 	static GLuint       g_FontTexture = 0;
 	static int          g_ShaderHandle = 0, g_VertHandle = 0, g_FragHandle = 0;
 	static int          g_AttribLocationTex = 0, g_AttribLocationProjMtx = 0;
 	static int          g_AttribLocationPosition = 0, g_AttribLocationUV = 0, g_AttribLocationColor = 0;
 	static unsigned int g_VboHandle = 0, g_VaoHandle = 0, g_ElementsHandle = 0;
 }

 // This is the main rendering function that you have to implement and provide to ImGui (via setting up 'RenderDrawListsFn' in the ImGuiIO structure)
 // If text or lines are blurry when integrating ImGui in your engine:
 // - in your Render function, try translating your projection matrix by (0.5f,0.5f) or (0.375f,0.375f)
 void ImGui_ImplGlfwGL3_RenderDrawLists(ImDrawData* draw_data)
 {
    // Backup GL state
    GLint last_program; glGetIntegerv(GL_CURRENT_PROGRAM, &last_program);
    GLint last_texture; glGetIntegerv(GL_TEXTURE_BINDING_2D, &last_texture);
    GLint last_array_buffer; glGetIntegerv(GL_ARRAY_BUFFER_BINDING, &last_array_buffer);
    GLint last_element_array_buffer; glGetIntegerv(GL_ELEMENT_ARRAY_BUFFER_BINDING, &last_element_array_buffer);
    GLint last_vertex_array; glGetIntegerv(GL_VERTEX_ARRAY_BINDING, &last_vertex_array);
    GLint last_blend_src; glGetIntegerv(GL_BLEND_SRC, &last_blend_src);
    GLint last_blend_dst; glGetIntegerv(GL_BLEND_DST, &last_blend_dst);
    GLint last_blend_equation_rgb; glGetIntegerv(GL_BLEND_EQUATION_RGB, &last_blend_equation_rgb);
    GLint last_blend_equation_alpha; glGetIntegerv(GL_BLEND_EQUATION_ALPHA, &last_blend_equation_alpha);
    GLint last_viewport[4]; glGetIntegerv(GL_VIEWPORT, last_viewport);
    GLboolean last_enable_blend = glIsEnabled(GL_BLEND);
    GLboolean last_enable_cull_face = glIsEnabled(GL_CULL_FACE);
    GLboolean last_enable_depth_test = glIsEnabled(GL_DEPTH_TEST);
    GLboolean last_enable_scissor_test = glIsEnabled(GL_SCISSOR_TEST);

    // Setup render state: alpha-blending enabled, no face culling, no depth testing, scissor enabled
    glEnable(GL_BLEND);
    glBlendEquation(GL_FUNC_ADD);
    glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
    glDisable(GL_CULL_FACE);
    glDisable(GL_DEPTH_TEST);
    glEnable(GL_SCISSOR_TEST);
    glActiveTexture(GL_TEXTURE0);

    // Handle cases of screen coordinates != from framebuffer coordinates (e.g. retina displays)
    ImGuiIO& io = ImGui::GetIO();
    int fb_width = (int)(io.DisplaySize.x * io.DisplayFramebufferScale.x);
    int fb_height = (int)(io.DisplaySize.y * io.DisplayFramebufferScale.y);
    if (fb_width == 0 || fb_height == 0)
        return;
    draw_data->ScaleClipRects(io.DisplayFramebufferScale);

    // Setup viewport, orthographic projection matrix
    glViewport(0, 0, (GLsizei)fb_width, (GLsizei)fb_height);
    const float ortho_projection[4][4] =
    {
        { 2.0f/io.DisplaySize.x, 0.0f,                   0.0f, 0.0f },
        { 0.0f,                  2.0f/-io.DisplaySize.y, 0.0f, 0.0f },
        { 0.0f,                  0.0f,                  -1.0f, 0.0f },
        {-1.0f,                  1.0f,                   0.0f, 1.0f },
    };
    glUseProgram(imgui_impl::g_ShaderHandle);
    glUniform1i(imgui_impl::g_AttribLocationTex, 0);
    glUniformMatrix4fv(imgui_impl::g_AttribLocationProjMtx, 1, GL_FALSE, &ortho_projection[0][0]);
    glBindVertexArray(imgui_impl::g_VaoHandle);

    for (int n = 0; n < draw_data->CmdListsCount; n++)
    {
        const ImDrawList* cmd_list = draw_data->CmdLists[n];
        const ImDrawIdx* idx_buffer_offset = 0;

        glBindBuffer(GL_ARRAY_BUFFER, imgui_impl::g_VboHandle);
        glBufferData(GL_ARRAY_BUFFER, (GLsizeiptr)cmd_list->VtxBuffer.size() * sizeof(ImDrawVert), (GLvoid*)&cmd_list->VtxBuffer.front(), GL_STREAM_DRAW);

        glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, imgui_impl::g_ElementsHandle);
        glBufferData(GL_ELEMENT_ARRAY_BUFFER, (GLsizeiptr)cmd_list->IdxBuffer.size() * sizeof(ImDrawIdx), (GLvoid*)&cmd_list->IdxBuffer.front(), GL_STREAM_DRAW);

        for (const ImDrawCmd* pcmd = cmd_list->CmdBuffer.begin(); pcmd != cmd_list->CmdBuffer.end(); pcmd++)
        {
            if (pcmd->UserCallback)
            {
                pcmd->UserCallback(cmd_list, pcmd);
            }
            else
            {
                glBindTexture(GL_TEXTURE_2D, (GLuint)(intptr_t)pcmd->TextureId);
                glScissor((int)pcmd->ClipRect.x, (int)(fb_height - pcmd->ClipRect.w), (int)(pcmd->ClipRect.z - pcmd->ClipRect.x), (int)(pcmd->ClipRect.w - pcmd->ClipRect.y));
                glDrawElements(GL_TRIANGLES, (GLsizei)pcmd->ElemCount, sizeof(ImDrawIdx) == 2 ? GL_UNSIGNED_SHORT : GL_UNSIGNED_INT, idx_buffer_offset);
            }
            idx_buffer_offset += pcmd->ElemCount;
        }
    }

    // Restore modified GL state
    glUseProgram(last_program);
    glBindTexture(GL_TEXTURE_2D, last_texture);
    glBindVertexArray(last_vertex_array);
    glBindBuffer(GL_ARRAY_BUFFER, last_array_buffer);
    glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, last_element_array_buffer);
    glBlendEquationSeparate(last_blend_equation_rgb, last_blend_equation_alpha);
    glBlendFunc(last_blend_src, last_blend_dst);
    if (last_enable_blend) glEnable(GL_BLEND); else glDisable(GL_BLEND);
    if (last_enable_cull_face) glEnable(GL_CULL_FACE); else glDisable(GL_CULL_FACE);
    if (last_enable_depth_test) glEnable(GL_DEPTH_TEST); else glDisable(GL_DEPTH_TEST);
    if (last_enable_scissor_test) glEnable(GL_SCISSOR_TEST); else glDisable(GL_SCISSOR_TEST);
    glViewport(last_viewport[0], last_viewport[1], (GLsizei)last_viewport[2], (GLsizei)last_viewport[3]);
 }

 static const char* ImGui_ImplGlfwGL3_GetClipboardText()
 {
    return glfwGetClipboardString(imgui_impl::g_Window);
 }

 static void ImGui_ImplGlfwGL3_SetClipboardText(const char* text)
 {
    glfwSetClipboardString(imgui_impl::g_Window, text);
 }

 void ImGui_ImplGlfwGL3_MouseButtonCallback(GLFWwindow*, int button, int action, int /*mods*/)
 {
    if (action == GLFW_PRESS && button >= 0 && button < 3)
 		imgui_impl::g_MousePressed[button] = true;
 }

 void ImGui_ImplGlfwGL3_ScrollCallback(GLFWwindow*, double /*xoffset*/, double yoffset)
 {
 	imgui_impl::g_MouseWheel += (float)yoffset; // Use fractional mouse wheel, 1.0 unit 5 lines.
 }

 void ImGui_ImplGlfwGL3_KeyCallback(GLFWwindow*, int key, int, int action, int mods)
 {
    ImGuiIO& io = ImGui::GetIO();
    if (action == GLFW_PRESS)
        io.KeysDown[key] = true;
    if (action == GLFW_RELEASE)
        io.KeysDown[key] = false;

    (void)mods; // Modifiers are not reliable across systems
    io.KeyCtrl = io.KeysDown[GLFW_KEY_LEFT_CONTROL] || io.KeysDown[GLFW_KEY_RIGHT_CONTROL];
    io.KeyShift = io.KeysDown[GLFW_KEY_LEFT_SHIFT] || io.KeysDown[GLFW_KEY_RIGHT_SHIFT];
    io.KeyAlt = io.KeysDown[GLFW_KEY_LEFT_ALT] || io.KeysDown[GLFW_KEY_RIGHT_ALT];
 }

 void ImGui_ImplGlfwGL3_CharCallback(GLFWwindow*, unsigned int c)
 {
    ImGuiIO& io = ImGui::GetIO();
    if (c > 0 && c < 0x10000)
        io.AddInputCharacter((unsigned short)c);
 }

 bool ImGui_ImplGlfwGL3_CreateFontsTexture()
 {
    // Build texture atlas
    ImGuiIO& io = ImGui::GetIO();
    unsigned char* pixels;
    int width, height;
    io.Fonts->GetTexDataAsRGBA32(&pixels, &width, &height);   // Load as RGBA 32-bits for OpenGL3 demo because it is more likely to be compatible with user's existing shader.

    // Upload texture to graphics system
    GLint last_texture;
    glGetIntegerv(GL_TEXTURE_BINDING_2D, &last_texture);
    glGenTextures(1, &imgui_impl::g_FontTexture);
    glBindTexture(GL_TEXTURE_2D, imgui_impl::g_FontTexture);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
    glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, width, height, 0, GL_RGBA, GL_UNSIGNED_BYTE, pixels);

    // Store our identifier
    io.Fonts->TexID = (void *)(intptr_t)imgui_impl::g_FontTexture;

    // Restore state
    glBindTexture(GL_TEXTURE_2D, last_texture);

    return true;
 }

 bool ImGui_ImplGlfwGL3_CreateDeviceObjects()
 {
    // Backup GL state
    GLint last_texture, last_array_buffer, last_vertex_array;
    glGetIntegerv(GL_TEXTURE_BINDING_2D, &last_texture);
    glGetIntegerv(GL_ARRAY_BUFFER_BINDING, &last_array_buffer);
    glGetIntegerv(GL_VERTEX_ARRAY_BINDING, &last_vertex_array);

    const GLchar *vertex_shader =
        "#version 330\n"
        "uniform mat4 ProjMtx;\n"
        "in vec2 Position;\n"
        "in vec2 UV;\n"
        "in vec4 Color;\n"
        "out vec2 Frag_UV;\n"
        "out vec4 Frag_Color;\n"
        "void main()\n"
        "{\n"
        "	Frag_UV = UV;\n"
        "	Frag_Color = Color;\n"
        "	gl_Position = ProjMtx * vec4(Position.xy,0,1);\n"
        "}\n";

    const GLchar* fragment_shader =
        "#version 330\n"
        "uniform sampler2D Texture;\n"
        "in vec2 Frag_UV;\n"
        "in vec4 Frag_Color;\n"
        "out vec4 Out_Color;\n"
        "void main()\n"
        "{\n"
        "	Out_Color = Frag_Color * texture( Texture, Frag_UV.st);\n"
        "}\n";

 	imgui_impl::g_ShaderHandle = glCreateProgram();
 	imgui_impl::g_VertHandle = glCreateShader(GL_VERTEX_SHADER);
 	imgui_impl::g_FragHandle = glCreateShader(GL_FRAGMENT_SHADER);
    glShaderSource(imgui_impl::g_VertHandle, 1, &vertex_shader, 0);
    glShaderSource(imgui_impl::g_FragHandle, 1, &fragment_shader, 0);
    glCompileShader(imgui_impl::g_VertHandle);
    glCompileShader(imgui_impl::g_FragHandle);
    glAttachShader(imgui_impl::g_ShaderHandle, imgui_impl::g_VertHandle);
    glAttachShader(imgui_impl::g_ShaderHandle, imgui_impl::g_FragHandle);
    glLinkProgram(imgui_impl::g_ShaderHandle);

 	imgui_impl::g_AttribLocationTex = glGetUniformLocation(imgui_impl::g_ShaderHandle, "Texture");
 	imgui_impl::g_AttribLocationProjMtx = glGetUniformLocation(imgui_impl::g_ShaderHandle, "ProjMtx");
 	imgui_impl::g_AttribLocationPosition = glGetAttribLocation(imgui_impl::g_ShaderHandle, "Position");
 	imgui_impl::g_AttribLocationUV = glGetAttribLocation(imgui_impl::g_ShaderHandle, "UV");
 	imgui_impl::g_AttribLocationColor = glGetAttribLocation(imgui_impl::g_ShaderHandle, "Color");

    glGenBuffers(1, &imgui_impl::g_VboHandle);
    glGenBuffers(1, &imgui_impl::g_ElementsHandle);

    glGenVertexArrays(1, &imgui_impl::g_VaoHandle);
    glBindVertexArray(imgui_impl::g_VaoHandle);
    glBindBuffer(GL_ARRAY_BUFFER, imgui_impl::g_VboHandle);
    glEnableVertexAttribArray(imgui_impl::g_AttribLocationPosition);
    glEnableVertexAttribArray(imgui_impl::g_AttribLocationUV);
    glEnableVertexAttribArray(imgui_impl::g_AttribLocationColor);

 #define OFFSETOF(TYPE, ELEMENT) ((size_t)&(((TYPE *)0)->ELEMENT))
    glVertexAttribPointer(imgui_impl::g_AttribLocationPosition, 2, GL_FLOAT, GL_FALSE, sizeof(ImDrawVert), (GLvoid*)OFFSETOF(ImDrawVert, pos));
    glVertexAttribPointer(imgui_impl::g_AttribLocationUV, 2, GL_FLOAT, GL_FALSE, sizeof(ImDrawVert), (GLvoid*)OFFSETOF(ImDrawVert, uv));
    glVertexAttribPointer(imgui_impl::g_AttribLocationColor, 4, GL_UNSIGNED_BYTE, GL_TRUE, sizeof(ImDrawVert), (GLvoid*)OFFSETOF(ImDrawVert, col));
 #undef OFFSETOF

    ImGui_ImplGlfwGL3_CreateFontsTexture();

    // Restore modified GL state
    glBindTexture(GL_TEXTURE_2D, last_texture);
    glBindBuffer(GL_ARRAY_BUFFER, last_array_buffer);
    glBindVertexArray(last_vertex_array);

    return true;
 }

 void    ImGui_ImplGlfwGL3_InvalidateDeviceObjects()
 {
    if (imgui_impl::g_VaoHandle) glDeleteVertexArrays(1, &imgui_impl::g_VaoHandle);
    if (imgui_impl::g_VboHandle) glDeleteBuffers(1, &imgui_impl::g_VboHandle);
    if (imgui_impl::g_ElementsHandle) glDeleteBuffers(1, &imgui_impl::g_ElementsHandle);
 	imgui_impl::g_VaoHandle = imgui_impl::g_VboHandle = imgui_impl::g_ElementsHandle = 0;

    glDetachShader(imgui_impl::g_ShaderHandle, imgui_impl::g_VertHandle);
    glDeleteShader(imgui_impl::g_VertHandle);
 	imgui_impl::g_VertHandle = 0;

    glDetachShader(imgui_impl::g_ShaderHandle, imgui_impl::g_FragHandle);
    glDeleteShader(imgui_impl::g_FragHandle);
 	imgui_impl::g_FragHandle = 0;

    glDeleteProgram(imgui_impl::g_ShaderHandle);
 	imgui_impl::g_ShaderHandle = 0;

    if (imgui_impl::g_FontTexture)
    {
        glDeleteTextures(1, &imgui_impl::g_FontTexture);
        ImGui::GetIO().Fonts->TexID = 0;
 		imgui_impl::g_FontTexture = 0;
    }
 }

 bool    ImGui_ImplGlfwGL3_Init(GLFWwindow* window, bool install_callbacks)
 {
 	imgui_impl::g_Window = window;

    ImGuiIO& io = ImGui::GetIO();
    io.KeyMap[ImGuiKey_Tab] = GLFW_KEY_TAB;                         // Keyboard mapping. ImGui will use those indices to peek into the io.KeyDown[] array.
    io.KeyMap[ImGuiKey_LeftArrow] = GLFW_KEY_LEFT;
    io.KeyMap[ImGuiKey_RightArrow] = GLFW_KEY_RIGHT;
    io.KeyMap[ImGuiKey_UpArrow] = GLFW_KEY_UP;
    io.KeyMap[ImGuiKey_DownArrow] = GLFW_KEY_DOWN;
    io.KeyMap[ImGuiKey_PageUp] = GLFW_KEY_PAGE_UP;
    io.KeyMap[ImGuiKey_PageDown] = GLFW_KEY_PAGE_DOWN;
    io.KeyMap[ImGuiKey_Home] = GLFW_KEY_HOME;
    io.KeyMap[ImGuiKey_End] = GLFW_KEY_END;
    io.KeyMap[ImGuiKey_Delete] = GLFW_KEY_DELETE;
    io.KeyMap[ImGuiKey_Backspace] = GLFW_KEY_BACKSPACE;
    io.KeyMap[ImGuiKey_Enter] = GLFW_KEY_ENTER;
 	io.KeyMap[ImGuiKey_Escape] = GLFW_KEY_ESCAPE;
 	io.KeyMap[ImGuiKey_Escape] = GLFW_KEY_ESCAPE;
    io.KeyMap[ImGuiKey_A] = GLFW_KEY_A;
    io.KeyMap[ImGuiKey_C] = GLFW_KEY_C;
    io.KeyMap[ImGuiKey_V] = GLFW_KEY_V;
    io.KeyMap[ImGuiKey_X] = GLFW_KEY_X;
    io.KeyMap[ImGuiKey_Y] = GLFW_KEY_Y;
    io.KeyMap[ImGuiKey_Z] = GLFW_KEY_Z;

    io.RenderDrawListsFn = ImGui_ImplGlfwGL3_RenderDrawLists;       // Alternatively you can set this to NULL and call ImGui::GetDrawData() after ImGui::Render() to get the same ImDrawData pointer.
    io.SetClipboardTextFn = ImGui_ImplGlfwGL3_SetClipboardText;
    io.GetClipboardTextFn = ImGui_ImplGlfwGL3_GetClipboardText;
 #ifdef _WIN32
    io.ImeWindowHandle = glfwGetWin32Window(imgui_impl::g_Window);
 #endif

    if (install_callbacks)
    {
        glfwSetMouseButtonCallback(window, ImGui_ImplGlfwGL3_MouseButtonCallback);
        glfwSetScrollCallback(window, ImGui_ImplGlfwGL3_ScrollCallback);
        glfwSetKeyCallback(window, ImGui_ImplGlfwGL3_KeyCallback);
        glfwSetCharCallback(window, ImGui_ImplGlfwGL3_CharCallback);
    }

    return true;
 }

 void ImGui_ImplGlfwGL3_Shutdown()
 {
    ImGui_ImplGlfwGL3_InvalidateDeviceObjects();
    ImGui::Shutdown();
 }

 void ImGui_ImplGlfwGL3_NewFrame()
 {
    if (!imgui_impl::g_FontTexture)
        ImGui_ImplGlfwGL3_CreateDeviceObjects();

    ImGuiIO& io = ImGui::GetIO();

    // Setup display size (every frame to accommodate for window resizing)
    int w, h;
    int display_w, display_h;
    glfwGetWindowSize(imgui_impl::g_Window, &w, &h);
    glfwGetFramebufferSize(imgui_impl::g_Window, &display_w, &display_h);
    io.DisplaySize = ImVec2((float)w, (float)h);
    io.DisplayFramebufferScale = ImVec2(w > 0 ? ((float)display_w / w) : 0, h > 0 ? ((float)display_h / h) : 0);

    // Setup time step
    double current_time =  glfwGetTime();
    io.DeltaTime = imgui_impl::g_Time > 0.0 ? (float)(current_time - imgui_impl::g_Time) : (float)(1.0f/60.0f);
 	imgui_impl::g_Time = current_time;

    // Setup inputs
    // (we already got mouse wheel, keyboard keys & characters from glfw callbacks polled in glfwPollEvents())
    if (glfwGetWindowAttrib(imgui_impl::g_Window, GLFW_FOCUSED))
    {
        double mouse_x, mouse_y;
        glfwGetCursorPos(imgui_impl::g_Window, &mouse_x, &mouse_y);
        io.MousePos = ImVec2((float)mouse_x, (float)mouse_y);   // Mouse position in screen coordinates (set to -1,-1 if no mouse / on another screen, etc.)
    }
    else
    {
        io.MousePos = ImVec2(-1,-1);
    }

    for (int i = 0; i < 3; i++)
    {
        io.MouseDown[i] = imgui_impl::g_MousePressed[i] || glfwGetMouseButton(imgui_impl::g_Window, i) != 0;    // If a mouse press event came, always pass it as "mouse held this frame", so we don't miss click-release events that are shorter than 1 frame.
 		imgui_impl::g_MousePressed[i] = false;
    }

    io.MouseWheel = imgui_impl::g_MouseWheel;
 	imgui_impl::g_MouseWheel = 0.0f;

    // Hide OS mouse cursor if ImGui is drawing it
    glfwSetInputMode(imgui_impl::g_Window, GLFW_CURSOR, io.MouseDrawCursor ? GLFW_CURSOR_HIDDEN : GLFW_CURSOR_NORMAL);

    // Start the frame
    ImGui::NewFrame();
 }
	// ImGui GLFW binding with OpenGL3 + shaders
	// You can copy and use unmodified imgui_impl_* files in your project. See main.cpp for an example of using this.
	// If you use this binding you'll need to call 4 functions: ImGui_ImplXXXX_Init(), ImGui_ImplXXXX_NewFrame(), ImGui::Render() and ImGui_ImplXXXX_Shutdown().
	// If you are new to ImGui, see examples/README.txt and documentation at the top of imgui.cpp.
	// https://github.com/ocornut/imgui

	#include <imgui.h>
	#include "imgui_impl_glfw_gl3.h"

	// GL_CORE/GLFW
	#include "gl_core_4_4.h"
	#include <GLFW\glfw3.h>

	#ifdef _WIN32
	#undef APIENTRY
	#define GLFW_EXPOSE_NATIVE_WIN32
	#define GLFW_EXPOSE_NATIVE_WGL
	#include <GLFW\glfw3native.h>
	#endif

	// Data
	namespace imgui_impl {
	static GLFWwindow* g_Window = nullptr;
	static double g_Time = 0.0f;
	static bool g_MousePressed[3] = { false, false, false };
	static float g_MouseWheel = 0.0f;
	static GLuint g_FontTexture = 0;
	static int g_ShaderHandle = 0, g_VertHandle = 0, g_FragHandle = 0;
	static int g_AttribLocationTex = 0, g_AttribLocationProjMtx = 0;
	static int g_AttribLocationPosition = 0, g_AttribLocationUV = 0, g_AttribLocationColor = 0;
	static unsigned int g_VboHandle = 0, g_VaoHandle = 0, g_ElementsHandle = 0;
	}

	// This is the main rendering function that you have to implement and provide to ImGui (via setting up 'RenderDrawListsFn' in the ImGuiIO structure)
	// If text or lines are blurry when integrating ImGui in your engine:
	// - in your Render function, try translating your projection matrix by (0.5f,0.5f) or (0.375f,0.375f)
	void ImGui_ImplGlfwGL3_RenderDrawLists(ImDrawData* draw_data)
	{
	// Backup GL state
	GLint last_program; glGetIntegerv(GL_CURRENT_PROGRAM, &last_program);
	GLint last_texture; glGetIntegerv(GL_TEXTURE_BINDING_2D, &last_texture);
	GLint last_array_buffer; glGetIntegerv(GL_ARRAY_BUFFER_BINDING, &last_array_buffer);
	GLint last_element_array_buffer; glGetIntegerv(GL_ELEMENT_ARRAY_BUFFER_BINDING, &last_element_array_buffer);
	GLint last_vertex_array; glGetIntegerv(GL_VERTEX_ARRAY_BINDING, &last_vertex_array);
	GLint last_blend_src; glGetIntegerv(GL_BLEND_SRC, &last_blend_src);
	GLint last_blend_dst; glGetIntegerv(GL_BLEND_DST, &last_blend_dst);
	GLint last_blend_equation_rgb; glGetIntegerv(GL_BLEND_EQUATION_RGB, &last_blend_equation_rgb);
	GLint last_blend_equation_alpha; glGetIntegerv(GL_BLEND_EQUATION_ALPHA, &last_blend_equation_alpha);
	GLint last_viewport[4]; glGetIntegerv(GL_VIEWPORT, last_viewport);
	GLboolean last_enable_blend = glIsEnabled(GL_BLEND);
	GLboolean last_enable_cull_face = glIsEnabled(GL_CULL_FACE);
	GLboolean last_enable_depth_test = glIsEnabled(GL_DEPTH_TEST);
	GLboolean last_enable_scissor_test = glIsEnabled(GL_SCISSOR_TEST);

	// Setup render state: alpha-blending enabled, no face culling, no depth testing, scissor enabled
	glEnable(GL_BLEND);
	glBlendEquation(GL_FUNC_ADD);
	glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
	glDisable(GL_CULL_FACE);
	glDisable(GL_DEPTH_TEST);
	glEnable(GL_SCISSOR_TEST);
	glActiveTexture(GL_TEXTURE0);

	// Handle cases of screen coordinates != from framebuffer coordinates (e.g. retina displays)
	ImGuiIO& io = ImGui::GetIO();
	int fb_width = (int)(io.DisplaySize.x * io.DisplayFramebufferScale.x);
	int fb_height = (int)(io.DisplaySize.y * io.DisplayFramebufferScale.y);
	if (fb_width == 0 \|\| fb_height == 0)
	return;
	draw_data->ScaleClipRects(io.DisplayFramebufferScale);

	// Setup viewport, orthographic projection matrix
	glViewport(0, 0, (GLsizei)fb_width, (GLsizei)fb_height);
	const float ortho_projection[4][4] =
	{
	{ 2.0f/io.DisplaySize.x, 0.0f, 0.0f, 0.0f },
	{ 0.0f, 2.0f/-io.DisplaySize.y, 0.0f, 0.0f },
	{ 0.0f, 0.0f, -1.0f, 0.0f },
	{-1.0f, 1.0f, 0.0f, 1.0f },
	};
	glUseProgram(imgui_impl::g_ShaderHandle);
	glUniform1i(imgui_impl::g_AttribLocationTex, 0);
	glUniformMatrix4fv(imgui_impl::g_AttribLocationProjMtx, 1, GL_FALSE, &ortho_projection[0][0]);
	glBindVertexArray(imgui_impl::g_VaoHandle);

	for (int n = 0; n < draw_data->CmdListsCount; n++)
	{
	const ImDrawList* cmd_list = draw_data->CmdLists[n];
	const ImDrawIdx* idx_buffer_offset = 0;

	glBindBuffer(GL_ARRAY_BUFFER, imgui_impl::g_VboHandle);
	glBufferData(GL_ARRAY_BUFFER, (GLsizeiptr)cmd_list->VtxBuffer.size() * sizeof(ImDrawVert), (GLvoid*)&cmd_list->VtxBuffer.front(), GL_STREAM_DRAW);

	glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, imgui_impl::g_ElementsHandle);
	glBufferData(GL_ELEMENT_ARRAY_BUFFER, (GLsizeiptr)cmd_list->IdxBuffer.size() * sizeof(ImDrawIdx), (GLvoid*)&cmd_list->IdxBuffer.front(), GL_STREAM_DRAW);

	for (const ImDrawCmd* pcmd = cmd_list->CmdBuffer.begin(); pcmd != cmd_list->CmdBuffer.end(); pcmd++)
	{
	if (pcmd->UserCallback)
	{
	pcmd->UserCallback(cmd_list, pcmd);
	}
	else
	{
	glBindTexture(GL_TEXTURE_2D, (GLuint)(intptr_t)pcmd->TextureId);
	glScissor((int)pcmd->ClipRect.x, (int)(fb_height - pcmd->ClipRect.w), (int)(pcmd->ClipRect.z - pcmd->ClipRect.x), (int)(pcmd->ClipRect.w - pcmd->ClipRect.y));
	glDrawElements(GL_TRIANGLES, (GLsizei)pcmd->ElemCount, sizeof(ImDrawIdx) == 2 ? GL_UNSIGNED_SHORT : GL_UNSIGNED_INT, idx_buffer_offset);
	}
	idx_buffer_offset += pcmd->ElemCount;
	}
	}

	// Restore modified GL state
	glUseProgram(last_program);
	glBindTexture(GL_TEXTURE_2D, last_texture);
	glBindVertexArray(last_vertex_array);
	glBindBuffer(GL_ARRAY_BUFFER, last_array_buffer);
	glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, last_element_array_buffer);
	glBlendEquationSeparate(last_blend_equation_rgb, last_blend_equation_alpha);
	glBlendFunc(last_blend_src, last_blend_dst);
	if (last_enable_blend) glEnable(GL_BLEND); else glDisable(GL_BLEND);
	if (last_enable_cull_face) glEnable(GL_CULL_FACE); else glDisable(GL_CULL_FACE);
	if (last_enable_depth_test) glEnable(GL_DEPTH_TEST); else glDisable(GL_DEPTH_TEST);
	if (last_enable_scissor_test) glEnable(GL_SCISSOR_TEST); else glDisable(GL_SCISSOR_TEST);
	glViewport(last_viewport[0], last_viewport[1], (GLsizei)last_viewport[2], (GLsizei)last_viewport[3]);
	}

	static const char* ImGui_ImplGlfwGL3_GetClipboardText()
	{
	return glfwGetClipboardString(imgui_impl::g_Window);
	}

	static void ImGui_ImplGlfwGL3_SetClipboardText(const char* text)
	{
	glfwSetClipboardString(imgui_impl::g_Window, text);
	}

	void ImGui_ImplGlfwGL3_MouseButtonCallback(GLFWwindow, int button, int action, int /mods*/)
	{
	if (action == GLFW_PRESS && button >= 0 && button < 3)
	imgui_impl::g_MousePressed[button] = true;
	}

	void ImGui_ImplGlfwGL3_ScrollCallback(GLFWwindow, double /xoffset*/, double yoffset)
	{
	imgui_impl::g_MouseWheel += (float)yoffset; // Use fractional mouse wheel, 1.0 unit 5 lines.
	}

	void ImGui_ImplGlfwGL3_KeyCallback(GLFWwindow*, int key, int, int action, int mods)
	{
	ImGuiIO& io = ImGui::GetIO();
	if (action == GLFW_PRESS)
	io.KeysDown[key] = true;
	if (action == GLFW_RELEASE)
	io.KeysDown[key] = false;

	(void)mods; // Modifiers are not reliable across systems
	io.KeyCtrl = io.KeysDown[GLFW_KEY_LEFT_CONTROL] \|\| io.KeysDown[GLFW_KEY_RIGHT_CONTROL];
	io.KeyShift = io.KeysDown[GLFW_KEY_LEFT_SHIFT] \|\| io.KeysDown[GLFW_KEY_RIGHT_SHIFT];
	io.KeyAlt = io.KeysDown[GLFW_KEY_LEFT_ALT] \|\| io.KeysDown[GLFW_KEY_RIGHT_ALT];
	}

	void ImGui_ImplGlfwGL3_CharCallback(GLFWwindow*, unsigned int c)
	{
	ImGuiIO& io = ImGui::GetIO();
	if (c > 0 && c < 0x10000)
	io.AddInputCharacter((unsigned short)c);
	}

	bool ImGui_ImplGlfwGL3_CreateFontsTexture()
	{
	// Build texture atlas
	ImGuiIO& io = ImGui::GetIO();
	unsigned char* pixels;
	int width, height;
	io.Fonts->GetTexDataAsRGBA32(&pixels, &width, &height); // Load as RGBA 32-bits for OpenGL3 demo because it is more likely to be compatible with user's existing shader.

	// Upload texture to graphics system
	GLint last_texture;
	glGetIntegerv(GL_TEXTURE_BINDING_2D, &last_texture);
	glGenTextures(1, &imgui_impl::g_FontTexture);
	glBindTexture(GL_TEXTURE_2D, imgui_impl::g_FontTexture);
	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
	glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, width, height, 0, GL_RGBA, GL_UNSIGNED_BYTE, pixels);

	// Store our identifier
	io.Fonts->TexID = (void *)(intptr_t)imgui_impl::g_FontTexture;

	// Restore state
	glBindTexture(GL_TEXTURE_2D, last_texture);

	return true;
	}

	bool ImGui_ImplGlfwGL3_CreateDeviceObjects()
	{
	// Backup GL state
	GLint last_texture, last_array_buffer, last_vertex_array;
	glGetIntegerv(GL_TEXTURE_BINDING_2D, &last_texture);
	glGetIntegerv(GL_ARRAY_BUFFER_BINDING, &last_array_buffer);
	glGetIntegerv(GL_VERTEX_ARRAY_BINDING, &last_vertex_array);

	const GLchar *vertex_shader =
	"#version 330\n"
	"uniform mat4 ProjMtx;\n"
	"in vec2 Position;\n"
	"in vec2 UV;\n"
	"in vec4 Color;\n"
	"out vec2 Frag_UV;\n"
	"out vec4 Frag_Color;\n"
	"void main()\n"
	"{\n"
	" Frag_UV = UV;\n"
	" Frag_Color = Color;\n"
	" gl_Position = ProjMtx * vec4(Position.xy,0,1);\n"
	"}\n";

	const GLchar* fragment_shader =
	"#version 330\n"
	"uniform sampler2D Texture;\n"
	"in vec2 Frag_UV;\n"
	"in vec4 Frag_Color;\n"
	"out vec4 Out_Color;\n"
	"void main()\n"
	"{\n"
	" Out_Color = Frag_Color * texture( Texture, Frag_UV.st);\n"
	"}\n";

	imgui_impl::g_ShaderHandle = glCreateProgram();
	imgui_impl::g_VertHandle = glCreateShader(GL_VERTEX_SHADER);
	imgui_impl::g_FragHandle = glCreateShader(GL_FRAGMENT_SHADER);
	glShaderSource(imgui_impl::g_VertHandle, 1, &vertex_shader, 0);
	glShaderSource(imgui_impl::g_FragHandle, 1, &fragment_shader, 0);
	glCompileShader(imgui_impl::g_VertHandle);
	glCompileShader(imgui_impl::g_FragHandle);
	glAttachShader(imgui_impl::g_ShaderHandle, imgui_impl::g_VertHandle);
	glAttachShader(imgui_impl::g_ShaderHandle, imgui_impl::g_FragHandle);
	glLinkProgram(imgui_impl::g_ShaderHandle);

	imgui_impl::g_AttribLocationTex = glGetUniformLocation(imgui_impl::g_ShaderHandle, "Texture");
	imgui_impl::g_AttribLocationProjMtx = glGetUniformLocation(imgui_impl::g_ShaderHandle, "ProjMtx");
	imgui_impl::g_AttribLocationPosition = glGetAttribLocation(imgui_impl::g_ShaderHandle, "Position");
	imgui_impl::g_AttribLocationUV = glGetAttribLocation(imgui_impl::g_ShaderHandle, "UV");
	imgui_impl::g_AttribLocationColor = glGetAttribLocation(imgui_impl::g_ShaderHandle, "Color");

	glGenBuffers(1, &imgui_impl::g_VboHandle);
	glGenBuffers(1, &imgui_impl::g_ElementsHandle);

	glGenVertexArrays(1, &imgui_impl::g_VaoHandle);
	glBindVertexArray(imgui_impl::g_VaoHandle);
	glBindBuffer(GL_ARRAY_BUFFER, imgui_impl::g_VboHandle);
	glEnableVertexAttribArray(imgui_impl::g_AttribLocationPosition);
	glEnableVertexAttribArray(imgui_impl::g_AttribLocationUV);
	glEnableVertexAttribArray(imgui_impl::g_AttribLocationColor);

	#define OFFSETOF(TYPE, ELEMENT) ((size_t)&(((TYPE *)0)->ELEMENT))
	glVertexAttribPointer(imgui_impl::g_AttribLocationPosition, 2, GL_FLOAT, GL_FALSE, sizeof(ImDrawVert), (GLvoid*)OFFSETOF(ImDrawVert, pos));
	glVertexAttribPointer(imgui_impl::g_AttribLocationUV, 2, GL_FLOAT, GL_FALSE, sizeof(ImDrawVert), (GLvoid*)OFFSETOF(ImDrawVert, uv));
	glVertexAttribPointer(imgui_impl::g_AttribLocationColor, 4, GL_UNSIGNED_BYTE, GL_TRUE, sizeof(ImDrawVert), (GLvoid*)OFFSETOF(ImDrawVert, col));
	#undef OFFSETOF

	ImGui_ImplGlfwGL3_CreateFontsTexture();

	// Restore modified GL state
	glBindTexture(GL_TEXTURE_2D, last_texture);
	glBindBuffer(GL_ARRAY_BUFFER, last_array_buffer);
	glBindVertexArray(last_vertex_array);

	return true;
	}

	void ImGui_ImplGlfwGL3_InvalidateDeviceObjects()
	{
	if (imgui_impl::g_VaoHandle) glDeleteVertexArrays(1, &imgui_impl::g_VaoHandle);
	if (imgui_impl::g_VboHandle) glDeleteBuffers(1, &imgui_impl::g_VboHandle);
	if (imgui_impl::g_ElementsHandle) glDeleteBuffers(1, &imgui_impl::g_ElementsHandle);
	imgui_impl::g_VaoHandle = imgui_impl::g_VboHandle = imgui_impl::g_ElementsHandle = 0;

	glDetachShader(imgui_impl::g_ShaderHandle, imgui_impl::g_VertHandle);
	glDeleteShader(imgui_impl::g_VertHandle);
	imgui_impl::g_VertHandle = 0;

	glDetachShader(imgui_impl::g_ShaderHandle, imgui_impl::g_FragHandle);
	glDeleteShader(imgui_impl::g_FragHandle);
	imgui_impl::g_FragHandle = 0;

	glDeleteProgram(imgui_impl::g_ShaderHandle);
	imgui_impl::g_ShaderHandle = 0;

	if (imgui_impl::g_FontTexture)
	{
	glDeleteTextures(1, &imgui_impl::g_FontTexture);
	ImGui::GetIO().Fonts->TexID = 0;
	imgui_impl::g_FontTexture = 0;
	}
	}

	bool ImGui_ImplGlfwGL3_Init(GLFWwindow* window, bool install_callbacks)
	{
	imgui_impl::g_Window = window;

	ImGuiIO& io = ImGui::GetIO();
	io.KeyMap[ImGuiKey_Tab] = GLFW_KEY_TAB; // Keyboard mapping. ImGui will use those indices to peek into the io.KeyDown[] array.
	io.KeyMap[ImGuiKey_LeftArrow] = GLFW_KEY_LEFT;
	io.KeyMap[ImGuiKey_RightArrow] = GLFW_KEY_RIGHT;
	io.KeyMap[ImGuiKey_UpArrow] = GLFW_KEY_UP;
	io.KeyMap[ImGuiKey_DownArrow] = GLFW_KEY_DOWN;
	io.KeyMap[ImGuiKey_PageUp] = GLFW_KEY_PAGE_UP;
	io.KeyMap[ImGuiKey_PageDown] = GLFW_KEY_PAGE_DOWN;
	io.KeyMap[ImGuiKey_Home] = GLFW_KEY_HOME;
	io.KeyMap[ImGuiKey_End] = GLFW_KEY_END;
	io.KeyMap[ImGuiKey_Delete] = GLFW_KEY_DELETE;
	io.KeyMap[ImGuiKey_Backspace] = GLFW_KEY_BACKSPACE;
	io.KeyMap[ImGuiKey_Enter] = GLFW_KEY_ENTER;
	io.KeyMap[ImGuiKey_Escape] = GLFW_KEY_ESCAPE;
	io.KeyMap[ImGuiKey_Escape] = GLFW_KEY_ESCAPE;
	io.KeyMap[ImGuiKey_A] = GLFW_KEY_A;
	io.KeyMap[ImGuiKey_C] = GLFW_KEY_C;
	io.KeyMap[ImGuiKey_V] = GLFW_KEY_V;
	io.KeyMap[ImGuiKey_X] = GLFW_KEY_X;
	io.KeyMap[ImGuiKey_Y] = GLFW_KEY_Y;
	io.KeyMap[ImGuiKey_Z] = GLFW_KEY_Z;

	io.RenderDrawListsFn = ImGui_ImplGlfwGL3_RenderDrawLists; // Alternatively you can set this to NULL and call ImGui::GetDrawData() after ImGui::Render() to get the same ImDrawData pointer.
	io.SetClipboardTextFn = ImGui_ImplGlfwGL3_SetClipboardText;
	io.GetClipboardTextFn = ImGui_ImplGlfwGL3_GetClipboardText;
	#ifdef _WIN32
	io.ImeWindowHandle = glfwGetWin32Window(imgui_impl::g_Window);
	#endif

	if (install_callbacks)
	{
	glfwSetMouseButtonCallback(window, ImGui_ImplGlfwGL3_MouseButtonCallback);
	glfwSetScrollCallback(window, ImGui_ImplGlfwGL3_ScrollCallback);
	glfwSetKeyCallback(window, ImGui_ImplGlfwGL3_KeyCallback);
	glfwSetCharCallback(window, ImGui_ImplGlfwGL3_CharCallback);
	}

	return true;
	}

	void ImGui_ImplGlfwGL3_Shutdown()
	{
	ImGui_ImplGlfwGL3_InvalidateDeviceObjects();
	ImGui::Shutdown();
	}

	void ImGui_ImplGlfwGL3_NewFrame()
	{
	if (!imgui_impl::g_FontTexture)
	ImGui_ImplGlfwGL3_CreateDeviceObjects();

	ImGuiIO& io = ImGui::GetIO();

	// Setup display size (every frame to accommodate for window resizing)
	int w, h;
	int display_w, display_h;
	glfwGetWindowSize(imgui_impl::g_Window, &w, &h);
	glfwGetFramebufferSize(imgui_impl::g_Window, &display_w, &display_h);
	io.DisplaySize = ImVec2((float)w, (float)h);
	io.DisplayFramebufferScale = ImVec2(w > 0 ? ((float)display_w / w) : 0, h > 0 ? ((float)display_h / h) : 0);

	// Setup time step
	double current_time = glfwGetTime();
	io.DeltaTime = imgui_impl::g_Time > 0.0 ? (float)(current_time - imgui_impl::g_Time) : (float)(1.0f/60.0f);
	imgui_impl::g_Time = current_time;

	// Setup inputs
	// (we already got mouse wheel, keyboard keys & characters from glfw callbacks polled in glfwPollEvents())
	if (glfwGetWindowAttrib(imgui_impl::g_Window, GLFW_FOCUSED))
	{
	double mouse_x, mouse_y;
	glfwGetCursorPos(imgui_impl::g_Window, &mouse_x, &mouse_y);
	io.MousePos = ImVec2((float)mouse_x, (float)mouse_y); // Mouse position in screen coordinates (set to -1,-1 if no mouse / on another screen, etc.)
	}
	else
	{
	io.MousePos = ImVec2(-1,-1);
	}

	for (int i = 0; i < 3; i++)
	{
	io.MouseDown[i] = imgui_impl::g_MousePressed[i] \|\| glfwGetMouseButton(imgui_impl::g_Window, i) != 0; // If a mouse press event came, always pass it as "mouse held this frame", so we don't miss click-release events that are shorter than 1 frame.
	imgui_impl::g_MousePressed[i] = false;
	}

	io.MouseWheel = imgui_impl::g_MouseWheel;
	imgui_impl::g_MouseWheel = 0.0f;

	// Hide OS mouse cursor if ImGui is drawing it
	glfwSetInputMode(imgui_impl::g_Window, GLFW_CURSOR, io.MouseDrawCursor ? GLFW_CURSOR_HIDDEN : GLFW_CURSOR_NORMAL);

	// Start the frame
	ImGui::NewFrame();
	}