From 2acdafe4f2cf844c6e21d77e83b605b7aa1aa75c Mon Sep 17 00:00:00 2001
From: Cedric Guillemet <cedric.guillemet@gmail.com>
Date: Mon, 25 May 2015 09:40:58 +0200
Subject: [PATCH 1/7] imgui_impl_sdl and main sample

---
 .../opengl_sdl_example/imgui_impl_sdl.cpp     | 286 ++++++++++++++++++
 examples/opengl_sdl_example/imgui_impl_sdl.h  |  12 +
 examples/opengl_sdl_example/main.cpp          | 109 +++++++
 3 files changed, 407 insertions(+)
 create mode 100644 examples/opengl_sdl_example/imgui_impl_sdl.cpp
 create mode 100644 examples/opengl_sdl_example/imgui_impl_sdl.h
 create mode 100644 examples/opengl_sdl_example/main.cpp

diff --git a/examples/opengl_sdl_example/imgui_impl_sdl.cpp b/examples/opengl_sdl_example/imgui_impl_sdl.cpp
new file mode 100644
index 000000000..2ac1f5be0
--- /dev/null
+++ b/examples/opengl_sdl_example/imgui_impl_sdl.cpp
@@ -0,0 +1,286 @@
+
+#ifdef _MSC_VER
+#include <Windows.h>
+#include <gl/GL.h>
+#include <gl/GLU.h>
+#endif
+
+#ifdef MACOSX
+#include <OpenGL/gl.h>
+#endif
+
+#include <SDL.h>
+#include <SDL_syswm.h>
+#include <imgui.h>
+#include "imgui_impl_sdl.h"
+
+// Data
+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;
+
+// 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)
+static void ImGui_ImplSdl_RenderDrawLists(ImDrawList** const cmd_lists, int cmd_lists_count)
+{
+    if (cmd_lists_count == 0)
+        return;
+
+    // We are using the OpenGL fixed pipeline to make the example code simpler to read!
+    // A probable faster way to render would be to collate all vertices from all cmd_lists into a single vertex buffer.
+    // Setup render state: alpha-blending enabled, no face culling, no depth testing, scissor enabled, vertex/texcoord/color pointers.
+    glPushAttrib(GL_ENABLE_BIT | GL_COLOR_BUFFER_BIT | GL_TRANSFORM_BIT);
+    glEnable(GL_BLEND);
+    glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
+    glDisable(GL_CULL_FACE);
+    glDisable(GL_DEPTH_TEST);
+    glEnable(GL_SCISSOR_TEST);
+    glEnableClientState(GL_VERTEX_ARRAY);
+    glEnableClientState(GL_TEXTURE_COORD_ARRAY);
+    glEnableClientState(GL_COLOR_ARRAY);
+    glEnable(GL_TEXTURE_2D);
+    //glUseProgram(0); // You may want this if using this code in an OpenGL 3+ context
+
+    // Setup orthographic projection matrix
+    const float width = ImGui::GetIO().DisplaySize.x;
+    const float height = ImGui::GetIO().DisplaySize.y;
+    glMatrixMode(GL_PROJECTION);
+    glPushMatrix();
+    glLoadIdentity();
+    glOrtho(0.0f, width, height, 0.0f, -1.0f, +1.0f);
+    glMatrixMode(GL_MODELVIEW);
+    glPushMatrix();
+    glLoadIdentity();
+
+    // Render command lists
+    #define OFFSETOF(TYPE, ELEMENT) ((size_t)&(((TYPE *)0)->ELEMENT))
+    for (int n = 0; n < cmd_lists_count; n++)
+    {
+        const ImDrawList* cmd_list = cmd_lists[n];
+        const unsigned char* vtx_buffer = (const unsigned char*)&cmd_list->vtx_buffer.front();
+        glVertexPointer(2, GL_FLOAT, sizeof(ImDrawVert), (void*)(vtx_buffer + OFFSETOF(ImDrawVert, pos)));
+        glTexCoordPointer(2, GL_FLOAT, sizeof(ImDrawVert), (void*)(vtx_buffer + OFFSETOF(ImDrawVert, uv)));
+        glColorPointer(4, GL_UNSIGNED_BYTE, sizeof(ImDrawVert), (void*)(vtx_buffer + OFFSETOF(ImDrawVert, col)));
+
+        int vtx_offset = 0;
+        for (size_t cmd_i = 0; cmd_i < cmd_list->commands.size(); cmd_i++)
+        {
+            const ImDrawCmd* pcmd = &cmd_list->commands[cmd_i];
+            if (pcmd->user_callback)
+            {
+                pcmd->user_callback(cmd_list, pcmd);
+            }
+            else
+            {
+                glBindTexture(GL_TEXTURE_2D, (GLuint)(intptr_t)pcmd->texture_id);
+                glScissor((int)pcmd->clip_rect.x, (int)(height - pcmd->clip_rect.w), (int)(pcmd->clip_rect.z - pcmd->clip_rect.x), (int)(pcmd->clip_rect.w - pcmd->clip_rect.y));
+                glDrawArrays(GL_TRIANGLES, vtx_offset, pcmd->vtx_count);
+            }
+            vtx_offset += pcmd->vtx_count;
+        }
+    }
+    #undef OFFSETOF
+
+    // Restore modified state
+    glDisableClientState(GL_COLOR_ARRAY);
+    glDisableClientState(GL_TEXTURE_COORD_ARRAY);
+    glDisableClientState(GL_VERTEX_ARRAY);
+    glBindTexture(GL_TEXTURE_2D, 0);
+    glMatrixMode(GL_MODELVIEW);
+    glPopMatrix();
+    glMatrixMode(GL_PROJECTION);
+    glPopMatrix();
+    glPopAttrib();
+}
+
+static const char* ImGui_ImplSdl_GetClipboardText()
+{
+	return SDL_GetClipboardText();
+}
+
+static void ImGui_ImplSdl_SetClipboardText(const char* text)
+{
+    SDL_SetClipboardText(text);
+}
+
+void ImGui_ImplSdl_KeyCallback(int key, bool down)
+{
+    ImGuiIO& io = ImGui::GetIO();
+    if (down)
+        io.KeysDown[key] = true;
+	else
+        io.KeysDown[key] = false;
+
+	io.KeyShift = ((SDL_GetModState() & KMOD_SHIFT) != 0);
+    io.KeyCtrl = ((SDL_GetModState() & KMOD_CTRL) != 0);
+	io.KeyAlt = ((SDL_GetModState() & KMOD_ALT) != 0);
+}
+
+void ImGui_ImplSdl_CharCallback(unsigned int c)
+{
+    ImGuiIO& io = ImGui::GetIO();
+    if (c > 0 && c < 0x10000)
+        io.AddInputCharacter((unsigned short)c);
+}
+
+bool ImGui_ImplSdl_CreateDeviceObjects()
+{
+    ImGuiIO& io = ImGui::GetIO();
+
+    // Build texture
+    unsigned char* pixels;
+    int width, height;
+    io.Fonts->GetTexDataAsAlpha8(&pixels, &width, &height);
+
+    // Create texture
+    glGenTextures(1, &g_FontTexture);
+    glBindTexture(GL_TEXTURE_2D, 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_ALPHA, width, height, 0, GL_ALPHA, GL_UNSIGNED_BYTE, pixels);
+
+    // Store our identifier
+    io.Fonts->TexID = (void *)(intptr_t)g_FontTexture;
+
+	io.Fonts->ClearInputData();
+	io.Fonts->ClearTexData();
+
+    return true;
+}
+
+void    ImGui_ImplSdl_InvalidateDeviceObjects()
+{
+    if (g_FontTexture)
+    {
+        glDeleteTextures(1, &g_FontTexture);
+        ImGui::GetIO().Fonts->TexID = 0;
+        g_FontTexture = 0;
+    }
+}
+
+bool    ImGui_ImplSdl_Init(SDL_Window *window)
+{
+    ImGuiIO& io = ImGui::GetIO();
+    io.KeyMap[ImGuiKey_Tab] = SDLK_TAB;                 // Keyboard mapping. ImGui will use those indices to peek into the io.KeyDown[] array.
+    io.KeyMap[ImGuiKey_LeftArrow] = SDL_SCANCODE_LEFT;
+    io.KeyMap[ImGuiKey_RightArrow] = SDL_SCANCODE_RIGHT;
+    io.KeyMap[ImGuiKey_UpArrow] = SDL_SCANCODE_UP;
+    io.KeyMap[ImGuiKey_DownArrow] = SDL_SCANCODE_DOWN;
+    io.KeyMap[ImGuiKey_Home] = SDL_SCANCODE_HOME;
+    io.KeyMap[ImGuiKey_End] = SDL_SCANCODE_END;
+    io.KeyMap[ImGuiKey_Delete] = SDLK_DELETE;
+    io.KeyMap[ImGuiKey_Backspace] = SDLK_BACKSPACE;
+    io.KeyMap[ImGuiKey_Enter] = SDLK_RETURN;
+    io.KeyMap[ImGuiKey_Escape] = SDLK_ESCAPE;
+    io.KeyMap[ImGuiKey_A] = SDLK_a;
+    io.KeyMap[ImGuiKey_C] = SDLK_c;
+    io.KeyMap[ImGuiKey_V] = SDLK_v;
+    io.KeyMap[ImGuiKey_X] = SDLK_x;
+    io.KeyMap[ImGuiKey_Y] = SDLK_y;
+    io.KeyMap[ImGuiKey_Z] = SDLK_z;
+	
+    io.RenderDrawListsFn = ImGui_ImplSdl_RenderDrawLists;
+    io.SetClipboardTextFn = ImGui_ImplSdl_SetClipboardText;
+    io.GetClipboardTextFn = ImGui_ImplSdl_GetClipboardText;
+	
+#ifdef _MSC_VER
+	SDL_SysWMinfo wmInfo;
+	SDL_VERSION(&wmInfo.version);
+	SDL_GetWindowWMInfo(window, &wmInfo);
+    io.ImeWindowHandle = wmInfo.info.win.window;
+#endif
+
+    return true;
+}
+
+void ImGui_ImplSdl_Shutdown()
+{
+    ImGui_ImplSdl_InvalidateDeviceObjects();
+    ImGui::Shutdown();
+}
+
+bool ImGui_ImplSdl_NewFrame(SDL_Window *window)
+{
+    if (!g_FontTexture)
+        ImGui_ImplSdl_CreateDeviceObjects();
+
+    ImGuiIO& io = ImGui::GetIO();
+
+	bool done(false);
+	SDL_Event event;
+	while (SDL_PollEvent(&event))
+	{
+		switch (event.type)
+		{
+		case SDL_QUIT:
+			done = true;
+			break;
+		case SDL_MOUSEWHEEL:
+			if (event.wheel.y>0 )
+			{
+				g_MouseWheel = 1;
+			}
+			if (event.wheel.y<0 )
+			{
+				g_MouseWheel = -1;
+			}
+			break;
+		case SDL_TEXTINPUT:
+			ImGui_ImplSdl_CharCallback(event.text.text[0]);
+			break;
+		case SDL_KEYUP:
+			ImGui_ImplSdl_KeyCallback(event.key.keysym.sym&~SDLK_SCANCODE_MASK, false);
+			break;
+		case SDL_KEYDOWN:
+			ImGui_ImplSdl_KeyCallback(event.key.keysym.sym&~SDLK_SCANCODE_MASK, true);
+			break;
+		default:
+			break;
+		}
+	}
+
+    // Setup display size (every frame to accommodate for window resizing)
+    int w, h;
+	SDL_GetWindowSize(window, &w, &h);
+    io.DisplaySize = ImVec2((float)w, (float)h);
+
+	// Time
+	Uint32	time = SDL_GetTicks();
+	double current_time = time / 1000.0;
+
+    io.DeltaTime = g_Time > 0.0 ? (float)(current_time - g_Time) : (float)(1.0f/60.0f);
+    g_Time = current_time;
+
+	int mx, my;
+	Uint32 mouseMask = SDL_GetMouseState(&mx, &my);
+
+    // Setup inputs
+    // (we already got mouse wheel, keyboard keys & characters from glfw callbacks polled in glfwPollEvents())
+	Uint32 windowFlags = SDL_GetWindowFlags(window);
+    if (windowFlags&SDL_WINDOW_MOUSE_FOCUS)
+    {
+    	io.MousePos = ImVec2((float)mx, (float)my);   // Mouse position, in pixels (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] = g_MousePressed[i] || (mouseMask&(1<<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.
+        g_MousePressed[i] = false;
+    }
+
+    io.MouseWheel = g_MouseWheel;
+    g_MouseWheel = 0.0f;
+
+    // Hide/show hardware mouse cursor
+    SDL_ShowCursor( io.MouseDrawCursor ? 0 : 1);
+
+    // Start the frame
+    ImGui::NewFrame();
+	return done;
+}
diff --git a/examples/opengl_sdl_example/imgui_impl_sdl.h b/examples/opengl_sdl_example/imgui_impl_sdl.h
new file mode 100644
index 000000000..a045b4ef3
--- /dev/null
+++ b/examples/opengl_sdl_example/imgui_impl_sdl.h
@@ -0,0 +1,12 @@
+
+struct		SDL_Window;
+
+bool        ImGui_ImplSdl_Init(SDL_Window *window);
+void        ImGui_ImplSdl_Shutdown();
+bool        ImGui_ImplSdl_NewFrame(SDL_Window *window);
+
+void        ImGui_ImplSdl_InvalidateDeviceObjects();
+bool        ImGui_ImplSdl_CreateDeviceObjects();
+
+void		ImGui_ImplSdl_KeyCallback(int key, int, bool down);
+void        ImGui_ImplSdl_CharCallback(unsigned int c);
diff --git a/examples/opengl_sdl_example/main.cpp b/examples/opengl_sdl_example/main.cpp
new file mode 100644
index 000000000..aa4a29668
--- /dev/null
+++ b/examples/opengl_sdl_example/main.cpp
@@ -0,0 +1,109 @@
+// ImGui - standalone example application for Glfw + OpenGL 2, using fixed pipeline
+
+#include <imgui.h>
+#include "imgui_impl_sdl.h"
+#include <stdio.h>
+
+#ifdef WIN32
+#include <Windows.h>
+#include <gl/GL.h>
+#include <gl/GLU.h>
+#endif
+
+#ifdef MACOSX
+#include <OpenGL/gl.h>
+
+#endif
+
+#include <SDL.h>
+
+int SDL_main(int /*argc*/, char* /*argv*/[])
+{
+    // Setup SDL
+	if (SDL_Init(SDL_INIT_EVERYTHING) != 0)
+        return -1;
+
+	// Init OpenGL
+	SDL_GL_SetAttribute(SDL_GL_DOUBLEBUFFER, 1);
+	SDL_GL_SetAttribute(SDL_GL_DEPTH_SIZE, 24);
+	SDL_GL_SetAttribute(SDL_GL_STENCIL_SIZE, 8);
+
+	SDL_GL_SetAttribute(SDL_GL_CONTEXT_MAJOR_VERSION, 2);
+	SDL_GL_SetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, 2);
+
+	int width(1024), height(576);
+
+	// SDL window
+	SDL_DisplayMode current;
+	SDL_GetCurrentDisplayMode(0, &current);
+	SDL_Window *window = SDL_CreateWindow( "ImGui OpenGL2/SDL2 example", SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED, width, height, SDL_WINDOW_OPENGL|SDL_WINDOW_RESIZABLE );
+  
+	// Create an OpenGL context associated with the window.
+	SDL_GLContext glcontext = SDL_GL_CreateContext(window);
+
+    // Setup ImGui binding
+    ImGui_ImplSdl_Init(window);
+    //ImGuiIO& io = ImGui::GetIO();
+    //ImFont* my_font0 = io.Fonts->AddFontDefault();
+    //ImFont* my_font1 = io.Fonts->AddFontFromFileTTF("../../extra_fonts/DroidSans.ttf", 16.0f);
+    //ImFont* my_font2 = io.Fonts->AddFontFromFileTTF("../../extra_fonts/Karla-Regular.ttf", 16.0f);
+    //ImFont* my_font3 = io.Fonts->AddFontFromFileTTF("../../extra_fonts/ProggyClean.ttf", 13.0f); my_font3->DisplayOffset.y += 1;
+    //ImFont* my_font4 = io.Fonts->AddFontFromFileTTF("../../extra_fonts/ProggyTiny.ttf", 10.0f); my_font4->DisplayOffset.y += 1;
+    //ImFont* my_font5 = io.Fonts->AddFontFromFileTTF("c:\\Windows\\Fonts\\ArialUni.ttf", 18.0f, io.Fonts->GetGlyphRangesJapanese());
+
+    bool show_test_window = true;
+    bool show_another_window = false;
+    ImVec4 clear_color = ImColor(114, 144, 154);
+
+	bool done(false);
+    // Main loop
+    while(!done)
+    {
+        done = ImGui_ImplSdl_NewFrame(window);
+
+        // 1. Show a simple window
+        // Tip: if we don't call ImGui::Begin()/ImGui::End() the widgets appears in a window automatically called "Debug"
+        {
+            static float f = 0.0f;
+            ImGui::Text("Hello, world!");
+            ImGui::SliderFloat("float", &f, 0.0f, 1.0f);
+            ImGui::ColorEdit3("clear color", (float*)&clear_color);
+            if (ImGui::Button("Test Window")) show_test_window ^= 1;
+            if (ImGui::Button("Another Window")) show_another_window ^= 1;
+            ImGui::Text("Application average %.3f ms/frame (%.1f FPS)", 1000.0f / ImGui::GetIO().Framerate, ImGui::GetIO().Framerate);
+        }
+
+        // 2. Show another simple window, this time using an explicit Begin/End pair
+        if (show_another_window)
+        {
+            ImGui::SetNextWindowSize(ImVec2(200,100), ImGuiSetCond_FirstUseEver);
+            ImGui::Begin("Another Window", &show_another_window);
+            ImGui::Text("Hello");
+            ImGui::End();
+        }
+
+        // 3. Show the ImGui test window. Most of the sample code is in ImGui::ShowTestWindow()
+        if (show_test_window)
+        {
+            ImGui::SetNextWindowPos(ImVec2(650, 20), ImGuiSetCond_FirstUseEver);
+            ImGui::ShowTestWindow(&show_test_window);
+        }
+
+        // Rendering
+        glViewport(0, 0, (int)ImGui::GetIO().DisplaySize.x, (int)ImGui::GetIO().DisplaySize.y);
+        glClearColor(clear_color.x, clear_color.y, clear_color.z, clear_color.w);
+        glClear(GL_COLOR_BUFFER_BIT);
+        ImGui::Render();
+        SDL_GL_SwapWindow(window);
+    }
+
+    // Cleanup
+    ImGui_ImplSdl_Shutdown();
+
+    SDL_GL_DeleteContext(glcontext);  
+	SDL_DestroyWindow(window);
+
+	SDL_Quit();
+
+    return 0;
+}

From b3ae2976c55f4aac310c69f16e4934b84eb1970d Mon Sep 17 00:00:00 2001
From: ocornut <omarcornut@gmail.com>
Date: Wed, 8 Jul 2015 09:46:55 -0600
Subject: [PATCH 2/7] SDL example: tweaks and fixes.

---
 .../opengl_sdl_example/imgui_impl_sdl.cpp     | 37 +++++++------------
 examples/opengl_sdl_example/imgui_impl_sdl.h  |  1 -
 examples/opengl_sdl_example/main.cpp          | 13 +++----
 3 files changed, 19 insertions(+), 32 deletions(-)

diff --git a/examples/opengl_sdl_example/imgui_impl_sdl.cpp b/examples/opengl_sdl_example/imgui_impl_sdl.cpp
index 2ac1f5be0..b1e129ece 100644
--- a/examples/opengl_sdl_example/imgui_impl_sdl.cpp
+++ b/examples/opengl_sdl_example/imgui_impl_sdl.cpp
@@ -1,4 +1,3 @@
-
 #ifdef _MSC_VER
 #include <Windows.h>
 #include <gl/GL.h>
@@ -25,9 +24,6 @@ static GLuint       g_FontTexture = 0;
 // - in your Render function, try translating your projection matrix by (0.5f,0.5f) or (0.375f,0.375f)
 static void ImGui_ImplSdl_RenderDrawLists(ImDrawList** const cmd_lists, int cmd_lists_count)
 {
-    if (cmd_lists_count == 0)
-        return;
-
     // We are using the OpenGL fixed pipeline to make the example code simpler to read!
     // A probable faster way to render would be to collate all vertices from all cmd_lists into a single vertex buffer.
     // Setup render state: alpha-blending enabled, no face culling, no depth testing, scissor enabled, vertex/texcoord/color pointers.
@@ -208,7 +204,7 @@ bool ImGui_ImplSdl_NewFrame(SDL_Window *window)
 
     ImGuiIO& io = ImGui::GetIO();
 
-	bool done(false);
+	bool done = false;
 	SDL_Event event;
 	while (SDL_PollEvent(&event))
 	{
@@ -218,14 +214,15 @@ bool ImGui_ImplSdl_NewFrame(SDL_Window *window)
 			done = true;
 			break;
 		case SDL_MOUSEWHEEL:
-			if (event.wheel.y>0 )
-			{
+			if (event.wheel.y > 0)
 				g_MouseWheel = 1;
-			}
-			if (event.wheel.y<0 )
-			{
+			if (event.wheel.y < 0)
 				g_MouseWheel = -1;
-			}
+			break;
+		case SDL_MOUSEBUTTONDOWN:
+			if (event.button.button == SDL_BUTTON_LEFT) g_MousePressed[0] = true;
+			if (event.button.button == SDL_BUTTON_RIGHT) g_MousePressed[1] = true;
+			if (event.button.button == SDL_BUTTON_MIDDLE) g_MousePressed[2] = true;
 			break;
 		case SDL_TEXTINPUT:
 			ImGui_ImplSdl_CharCallback(event.text.text[0]);
@@ -258,27 +255,21 @@ bool ImGui_ImplSdl_NewFrame(SDL_Window *window)
 
     // Setup inputs
     // (we already got mouse wheel, keyboard keys & characters from glfw callbacks polled in glfwPollEvents())
-	Uint32 windowFlags = SDL_GetWindowFlags(window);
-    if (windowFlags&SDL_WINDOW_MOUSE_FOCUS)
-    {
+    if (SDL_GetWindowFlags(window) & SDL_WINDOW_MOUSE_FOCUS)
     	io.MousePos = ImVec2((float)mx, (float)my);   // Mouse position, in pixels (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] = g_MousePressed[i] || (mouseMask&(1<<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.
-        g_MousePressed[i] = false;
-    }
+	io.MouseDown[0] = g_MousePressed[0] || (mouseMask & SDL_BUTTON(SDL_BUTTON_LEFT)) != 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.
+	io.MouseDown[1] = g_MousePressed[1] || (mouseMask & SDL_BUTTON(SDL_BUTTON_RIGHT)) != 0;
+	io.MouseDown[2] = g_MousePressed[2] || (mouseMask & SDL_BUTTON(SDL_BUTTON_MIDDLE)) != 0;
+    g_MousePressed[0] = g_MousePressed[1] = g_MousePressed[2] = false;
 
     io.MouseWheel = g_MouseWheel;
     g_MouseWheel = 0.0f;
 
     // Hide/show hardware mouse cursor
-    SDL_ShowCursor( io.MouseDrawCursor ? 0 : 1);
+    SDL_ShowCursor(io.MouseDrawCursor ? 0 : 1);
 
     // Start the frame
     ImGui::NewFrame();
diff --git a/examples/opengl_sdl_example/imgui_impl_sdl.h b/examples/opengl_sdl_example/imgui_impl_sdl.h
index a045b4ef3..d8f3c2ecf 100644
--- a/examples/opengl_sdl_example/imgui_impl_sdl.h
+++ b/examples/opengl_sdl_example/imgui_impl_sdl.h
@@ -1,4 +1,3 @@
-
 struct		SDL_Window;
 
 bool        ImGui_ImplSdl_Init(SDL_Window *window);
diff --git a/examples/opengl_sdl_example/main.cpp b/examples/opengl_sdl_example/main.cpp
index aa4a29668..c6aa24e9e 100644
--- a/examples/opengl_sdl_example/main.cpp
+++ b/examples/opengl_sdl_example/main.cpp
@@ -1,4 +1,4 @@
-// ImGui - standalone example application for Glfw + OpenGL 2, using fixed pipeline
+// ImGui - standalone example application for SDL2
 
 #include <imgui.h>
 #include "imgui_impl_sdl.h"
@@ -12,10 +12,10 @@
 
 #ifdef MACOSX
 #include <OpenGL/gl.h>
-
 #endif
 
 #include <SDL.h>
+#include <SDL_OpenGL.h>
 
 int SDL_main(int /*argc*/, char* /*argv*/[])
 {
@@ -27,16 +27,13 @@ int SDL_main(int /*argc*/, char* /*argv*/[])
 	SDL_GL_SetAttribute(SDL_GL_DOUBLEBUFFER, 1);
 	SDL_GL_SetAttribute(SDL_GL_DEPTH_SIZE, 24);
 	SDL_GL_SetAttribute(SDL_GL_STENCIL_SIZE, 8);
-
 	SDL_GL_SetAttribute(SDL_GL_CONTEXT_MAJOR_VERSION, 2);
 	SDL_GL_SetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, 2);
 
-	int width(1024), height(576);
-
 	// SDL window
 	SDL_DisplayMode current;
 	SDL_GetCurrentDisplayMode(0, &current);
-	SDL_Window *window = SDL_CreateWindow( "ImGui OpenGL2/SDL2 example", SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED, width, height, SDL_WINDOW_OPENGL|SDL_WINDOW_RESIZABLE );
+	SDL_Window *window = SDL_CreateWindow("ImGui SDL2+OpenGL example", SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED, 1280, 720, SDL_WINDOW_OPENGL|SDL_WINDOW_RESIZABLE);
   
 	// Create an OpenGL context associated with the window.
 	SDL_GLContext glcontext = SDL_GL_CreateContext(window);
@@ -55,9 +52,9 @@ int SDL_main(int /*argc*/, char* /*argv*/[])
     bool show_another_window = false;
     ImVec4 clear_color = ImColor(114, 144, 154);
 
-	bool done(false);
     // Main loop
-    while(!done)
+	bool done = false;
+    while (!done)
     {
         done = ImGui_ImplSdl_NewFrame(window);
 

From 44c23e0eed69a2587d16e3342bb0d58eaa105bfd Mon Sep 17 00:00:00 2001
From: ocornut <omarcornut@gmail.com>
Date: Wed, 8 Jul 2015 09:48:10 -0600
Subject: [PATCH 3/7] Allowing DeltaTime==0.0f to not assert

---
 imgui.cpp | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/imgui.cpp b/imgui.cpp
index 507e8d832..9e93dfdfe 100644
--- a/imgui.cpp
+++ b/imgui.cpp
@@ -2080,10 +2080,10 @@ void ImGui::NewFrame()
     ImGuiState& g = *GImGui;
 
     // Check user data
-    IM_ASSERT(g.IO.DeltaTime > 0.0f);
+    IM_ASSERT(g.IO.DeltaTime >= 0.0f);
     IM_ASSERT(g.IO.DisplaySize.x >= 0.0f && g.IO.DisplaySize.y >= 0.0f);
     IM_ASSERT(g.IO.RenderDrawListsFn != NULL);       // Must be implemented
-    IM_ASSERT(g.IO.Fonts->Fonts.Size > 0);         // Font Atlas not created. Did you call io.Fonts->GetTexDataAsRGBA32 / GetTexDataAsAlpha8 ?
+    IM_ASSERT(g.IO.Fonts->Fonts.Size > 0);           // Font Atlas not created. Did you call io.Fonts->GetTexDataAsRGBA32 / GetTexDataAsAlpha8 ?
     IM_ASSERT(g.IO.Fonts->Fonts[0]->IsLoaded());     // Font Atlas not created. Did you call io.Fonts->GetTexDataAsRGBA32 / GetTexDataAsAlpha8 ?
 
     if (!g.Initialized)

From b7a2a6b23fc215aa7c82baa4a334f5cd59c5fb82 Mon Sep 17 00:00:00 2001
From: ocornut <omarcornut@gmail.com>
Date: Wed, 8 Jul 2015 09:49:32 -0600
Subject: [PATCH 4/7] SDL example: renamed folder, added in README

---
 examples/README.txt                                            | 3 +++
 .../imgui_impl_sdl.cpp                                         | 0
 .../imgui_impl_sdl.h                                           | 0
 examples/{opengl_sdl_example => sdl_opengl_example}/main.cpp   | 0
 4 files changed, 3 insertions(+)
 rename examples/{opengl_sdl_example => sdl_opengl_example}/imgui_impl_sdl.cpp (100%)
 rename examples/{opengl_sdl_example => sdl_opengl_example}/imgui_impl_sdl.h (100%)
 rename examples/{opengl_sdl_example => sdl_opengl_example}/main.cpp (100%)

diff --git a/examples/README.txt b/examples/README.txt
index 0a5ad0e05..f958d526f 100644
--- a/examples/README.txt
+++ b/examples/README.txt
@@ -25,3 +25,6 @@ directx11_example/
 ios_example/
 	iOS example.
 	Using Synergy to access keyboard/mouse data from server computer. Synergy keyboard integration is rather hacky.
+
+sdl_opengl_example/
+	SDL2 + OpenGL example.
diff --git a/examples/opengl_sdl_example/imgui_impl_sdl.cpp b/examples/sdl_opengl_example/imgui_impl_sdl.cpp
similarity index 100%
rename from examples/opengl_sdl_example/imgui_impl_sdl.cpp
rename to examples/sdl_opengl_example/imgui_impl_sdl.cpp
diff --git a/examples/opengl_sdl_example/imgui_impl_sdl.h b/examples/sdl_opengl_example/imgui_impl_sdl.h
similarity index 100%
rename from examples/opengl_sdl_example/imgui_impl_sdl.h
rename to examples/sdl_opengl_example/imgui_impl_sdl.h
diff --git a/examples/opengl_sdl_example/main.cpp b/examples/sdl_opengl_example/main.cpp
similarity index 100%
rename from examples/opengl_sdl_example/main.cpp
rename to examples/sdl_opengl_example/main.cpp

From 416752800182d60c9ad0b82e8d843e77ebf6c73b Mon Sep 17 00:00:00 2001
From: ocornut <omarcornut@gmail.com>
Date: Wed, 8 Jul 2015 10:10:54 -0600
Subject: [PATCH 5/7] SDL example: moved event loop to main.cpp , adding page
 up/page down. (#226)

---
 .../sdl_opengl_example/imgui_impl_sdl.cpp     | 93 ++++++++-----------
 examples/sdl_opengl_example/imgui_impl_sdl.h  |  8 +-
 examples/sdl_opengl_example/main.cpp          |  9 +-
 3 files changed, 53 insertions(+), 57 deletions(-)

diff --git a/examples/sdl_opengl_example/imgui_impl_sdl.cpp b/examples/sdl_opengl_example/imgui_impl_sdl.cpp
index b1e129ece..8c9b2f16d 100644
--- a/examples/sdl_opengl_example/imgui_impl_sdl.cpp
+++ b/examples/sdl_opengl_example/imgui_impl_sdl.cpp
@@ -101,24 +101,46 @@ static void ImGui_ImplSdl_SetClipboardText(const char* text)
     SDL_SetClipboardText(text);
 }
 
-void ImGui_ImplSdl_KeyCallback(int key, bool down)
+bool ImGui_ImplSdl_EventCallback(const SDL_Event& event)
 {
     ImGuiIO& io = ImGui::GetIO();
-    if (down)
-        io.KeysDown[key] = true;
-	else
-        io.KeysDown[key] = false;
-
-	io.KeyShift = ((SDL_GetModState() & KMOD_SHIFT) != 0);
-    io.KeyCtrl = ((SDL_GetModState() & KMOD_CTRL) != 0);
-	io.KeyAlt = ((SDL_GetModState() & KMOD_ALT) != 0);
-}
-
-void ImGui_ImplSdl_CharCallback(unsigned int c)
-{
-    ImGuiIO& io = ImGui::GetIO();
-    if (c > 0 && c < 0x10000)
-        io.AddInputCharacter((unsigned short)c);
+    switch (event.type)
+    {
+    case SDL_MOUSEWHEEL:
+        {
+            if (event.wheel.y > 0)
+                g_MouseWheel = 1;
+            if (event.wheel.y < 0)
+                g_MouseWheel = -1;
+            return true;
+        }
+    case SDL_MOUSEBUTTONDOWN:
+        {
+            if (event.button.button == SDL_BUTTON_LEFT) g_MousePressed[0] = true;
+            if (event.button.button == SDL_BUTTON_RIGHT) g_MousePressed[1] = true;
+            if (event.button.button == SDL_BUTTON_MIDDLE) g_MousePressed[2] = true;
+            return true;
+        }
+    case SDL_TEXTINPUT:
+        {
+            ImGuiIO& io = ImGui::GetIO();
+            unsigned int c = event.text.text[0];
+            if (c > 0 && c < 0x10000)
+                io.AddInputCharacter((unsigned short)c);
+            return true;
+        }
+    case SDL_KEYDOWN:
+    case SDL_KEYUP:
+        {
+            int key = event.key.keysym.sym & ~SDLK_SCANCODE_MASK;
+            io.KeysDown[key] = (event.type == SDL_KEYDOWN);
+            io.KeyShift = ((SDL_GetModState() & KMOD_SHIFT) != 0);
+            io.KeyCtrl = ((SDL_GetModState() & KMOD_CTRL) != 0);
+            io.KeyAlt = ((SDL_GetModState() & KMOD_ALT) != 0);
+            return true;
+        }
+    }
+    return false;
 }
 
 bool ImGui_ImplSdl_CreateDeviceObjects()
@@ -164,6 +186,8 @@ bool    ImGui_ImplSdl_Init(SDL_Window *window)
     io.KeyMap[ImGuiKey_RightArrow] = SDL_SCANCODE_RIGHT;
     io.KeyMap[ImGuiKey_UpArrow] = SDL_SCANCODE_UP;
     io.KeyMap[ImGuiKey_DownArrow] = SDL_SCANCODE_DOWN;
+    io.KeyMap[ImGuiKey_PageUp] = SDL_SCANCODE_PAGEUP;
+    io.KeyMap[ImGuiKey_PageDown] = SDL_SCANCODE_PAGEDOWN;
     io.KeyMap[ImGuiKey_Home] = SDL_SCANCODE_HOME;
     io.KeyMap[ImGuiKey_End] = SDL_SCANCODE_END;
     io.KeyMap[ImGuiKey_Delete] = SDLK_DELETE;
@@ -197,47 +221,13 @@ void ImGui_ImplSdl_Shutdown()
     ImGui::Shutdown();
 }
 
-bool ImGui_ImplSdl_NewFrame(SDL_Window *window)
+void ImGui_ImplSdl_NewFrame(SDL_Window *window)
 {
     if (!g_FontTexture)
         ImGui_ImplSdl_CreateDeviceObjects();
 
     ImGuiIO& io = ImGui::GetIO();
 
-	bool done = false;
-	SDL_Event event;
-	while (SDL_PollEvent(&event))
-	{
-		switch (event.type)
-		{
-		case SDL_QUIT:
-			done = true;
-			break;
-		case SDL_MOUSEWHEEL:
-			if (event.wheel.y > 0)
-				g_MouseWheel = 1;
-			if (event.wheel.y < 0)
-				g_MouseWheel = -1;
-			break;
-		case SDL_MOUSEBUTTONDOWN:
-			if (event.button.button == SDL_BUTTON_LEFT) g_MousePressed[0] = true;
-			if (event.button.button == SDL_BUTTON_RIGHT) g_MousePressed[1] = true;
-			if (event.button.button == SDL_BUTTON_MIDDLE) g_MousePressed[2] = true;
-			break;
-		case SDL_TEXTINPUT:
-			ImGui_ImplSdl_CharCallback(event.text.text[0]);
-			break;
-		case SDL_KEYUP:
-			ImGui_ImplSdl_KeyCallback(event.key.keysym.sym&~SDLK_SCANCODE_MASK, false);
-			break;
-		case SDL_KEYDOWN:
-			ImGui_ImplSdl_KeyCallback(event.key.keysym.sym&~SDLK_SCANCODE_MASK, true);
-			break;
-		default:
-			break;
-		}
-	}
-
     // Setup display size (every frame to accommodate for window resizing)
     int w, h;
 	SDL_GetWindowSize(window, &w, &h);
@@ -273,5 +263,4 @@ bool ImGui_ImplSdl_NewFrame(SDL_Window *window)
 
     // Start the frame
     ImGui::NewFrame();
-	return done;
 }
diff --git a/examples/sdl_opengl_example/imgui_impl_sdl.h b/examples/sdl_opengl_example/imgui_impl_sdl.h
index d8f3c2ecf..08d6df695 100644
--- a/examples/sdl_opengl_example/imgui_impl_sdl.h
+++ b/examples/sdl_opengl_example/imgui_impl_sdl.h
@@ -1,11 +1,11 @@
-struct		SDL_Window;
+struct SDL_Window;
+typedef union SDL_Event SDL_Event;
 
 bool        ImGui_ImplSdl_Init(SDL_Window *window);
 void        ImGui_ImplSdl_Shutdown();
-bool        ImGui_ImplSdl_NewFrame(SDL_Window *window);
+void        ImGui_ImplSdl_NewFrame(SDL_Window *window);
+bool        ImGui_ImplSdl_EventCallback(const SDL_Event& event);
 
 void        ImGui_ImplSdl_InvalidateDeviceObjects();
 bool        ImGui_ImplSdl_CreateDeviceObjects();
 
-void		ImGui_ImplSdl_KeyCallback(int key, int, bool down);
-void        ImGui_ImplSdl_CharCallback(unsigned int c);
diff --git a/examples/sdl_opengl_example/main.cpp b/examples/sdl_opengl_example/main.cpp
index c6aa24e9e..333612127 100644
--- a/examples/sdl_opengl_example/main.cpp
+++ b/examples/sdl_opengl_example/main.cpp
@@ -56,7 +56,14 @@ int SDL_main(int /*argc*/, char* /*argv*/[])
 	bool done = false;
     while (!done)
     {
-        done = ImGui_ImplSdl_NewFrame(window);
+        SDL_Event event;
+        while (SDL_PollEvent(&event))
+        {
+            ImGui_ImplSdl_EventCallback(event);
+            if (event.type == SDL_QUIT)
+                done = true;
+        }
+        ImGui_ImplSdl_NewFrame(window);
 
         // 1. Show a simple window
         // Tip: if we don't call ImGui::Begin()/ImGui::End() the widgets appears in a window automatically called "Debug"

From 22e099366f0e4c0ec4351ceac3abbceb9252f806 Mon Sep 17 00:00:00 2001
From: ocornut <omarcornut@gmail.com>
Date: Wed, 8 Jul 2015 10:20:08 -0600
Subject: [PATCH 6/7] SDL example: further cleanup to match other examples
 (#233 #226)

---
 .../sdl_opengl_example/imgui_impl_sdl.cpp     | 11 +--------
 examples/sdl_opengl_example/imgui_impl_sdl.h  |  1 -
 examples/sdl_opengl_example/main.cpp          | 23 +++----------------
 3 files changed, 4 insertions(+), 31 deletions(-)

diff --git a/examples/sdl_opengl_example/imgui_impl_sdl.cpp b/examples/sdl_opengl_example/imgui_impl_sdl.cpp
index 8c9b2f16d..b22250b8e 100644
--- a/examples/sdl_opengl_example/imgui_impl_sdl.cpp
+++ b/examples/sdl_opengl_example/imgui_impl_sdl.cpp
@@ -1,15 +1,6 @@
-#ifdef _MSC_VER
-#include <Windows.h>
-#include <gl/GL.h>
-#include <gl/GLU.h>
-#endif
-
-#ifdef MACOSX
-#include <OpenGL/gl.h>
-#endif
-
 #include <SDL.h>
 #include <SDL_syswm.h>
+#include <SDL_OpenGL.h>
 #include <imgui.h>
 #include "imgui_impl_sdl.h"
 
diff --git a/examples/sdl_opengl_example/imgui_impl_sdl.h b/examples/sdl_opengl_example/imgui_impl_sdl.h
index 08d6df695..6d56b2e0e 100644
--- a/examples/sdl_opengl_example/imgui_impl_sdl.h
+++ b/examples/sdl_opengl_example/imgui_impl_sdl.h
@@ -8,4 +8,3 @@ bool        ImGui_ImplSdl_EventCallback(const SDL_Event& event);
 
 void        ImGui_ImplSdl_InvalidateDeviceObjects();
 bool        ImGui_ImplSdl_CreateDeviceObjects();
-
diff --git a/examples/sdl_opengl_example/main.cpp b/examples/sdl_opengl_example/main.cpp
index 333612127..87e5c794f 100644
--- a/examples/sdl_opengl_example/main.cpp
+++ b/examples/sdl_opengl_example/main.cpp
@@ -1,41 +1,26 @@
-// ImGui - standalone example application for SDL2
+// ImGui - standalone example application for SDL2 + OpenGL
 
 #include <imgui.h>
 #include "imgui_impl_sdl.h"
 #include <stdio.h>
-
-#ifdef WIN32
-#include <Windows.h>
-#include <gl/GL.h>
-#include <gl/GLU.h>
-#endif
-
-#ifdef MACOSX
-#include <OpenGL/gl.h>
-#endif
-
 #include <SDL.h>
 #include <SDL_OpenGL.h>
 
-int SDL_main(int /*argc*/, char* /*argv*/[])
+int SDL_main(int, char**)
 {
     // Setup SDL
 	if (SDL_Init(SDL_INIT_EVERYTHING) != 0)
         return -1;
 
-	// Init OpenGL
+    // Setup window
 	SDL_GL_SetAttribute(SDL_GL_DOUBLEBUFFER, 1);
 	SDL_GL_SetAttribute(SDL_GL_DEPTH_SIZE, 24);
 	SDL_GL_SetAttribute(SDL_GL_STENCIL_SIZE, 8);
 	SDL_GL_SetAttribute(SDL_GL_CONTEXT_MAJOR_VERSION, 2);
 	SDL_GL_SetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, 2);
-
-	// SDL window
 	SDL_DisplayMode current;
 	SDL_GetCurrentDisplayMode(0, &current);
 	SDL_Window *window = SDL_CreateWindow("ImGui SDL2+OpenGL example", SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED, 1280, 720, SDL_WINDOW_OPENGL|SDL_WINDOW_RESIZABLE);
-  
-	// Create an OpenGL context associated with the window.
 	SDL_GLContext glcontext = SDL_GL_CreateContext(window);
 
     // Setup ImGui binding
@@ -103,10 +88,8 @@ int SDL_main(int /*argc*/, char* /*argv*/[])
 
     // Cleanup
     ImGui_ImplSdl_Shutdown();
-
     SDL_GL_DeleteContext(glcontext);  
 	SDL_DestroyWindow(window);
-
 	SDL_Quit();
 
     return 0;

From a14f6696a3e52d81127175fcc32c7c1df3fc92dd Mon Sep 17 00:00:00 2001
From: ocornut <omarcornut@gmail.com>
Date: Wed, 8 Jul 2015 10:27:25 -0600
Subject: [PATCH 7/7] SDL example: more cleanup to match other examples (#233
 #226)

---
 .../opengl3_example/imgui_impl_glfw_gl3.cpp   |  3 ---
 examples/opengl_example/imgui_impl_glfw.cpp   |  3 ---
 .../sdl_opengl_example/imgui_impl_sdl.cpp     | 20 ++++++++++---------
 examples/sdl_opengl_example/imgui_impl_sdl.h  |  4 ++++
 4 files changed, 15 insertions(+), 15 deletions(-)

diff --git a/examples/opengl3_example/imgui_impl_glfw_gl3.cpp b/examples/opengl3_example/imgui_impl_glfw_gl3.cpp
index 2328a08a2..fb3286de8 100644
--- a/examples/opengl3_example/imgui_impl_glfw_gl3.cpp
+++ b/examples/opengl3_example/imgui_impl_glfw_gl3.cpp
@@ -31,9 +31,6 @@ static unsigned int g_VboHandle = 0, g_VaoHandle = 0;
 // - in your Render function, try translating your projection matrix by (0.5f,0.5f) or (0.375f,0.375f)
 static void ImGui_ImplGlfwGL3_RenderDrawLists(ImDrawList** const cmd_lists, int cmd_lists_count)
 {
-    if (cmd_lists_count == 0)
-        return;
-
     // Setup render state: alpha-blending enabled, no face culling, no depth testing, scissor enabled
     GLint last_program, last_texture;
     glGetIntegerv(GL_CURRENT_PROGRAM, &last_program);
diff --git a/examples/opengl_example/imgui_impl_glfw.cpp b/examples/opengl_example/imgui_impl_glfw.cpp
index 4756947a4..d289a7ada 100644
--- a/examples/opengl_example/imgui_impl_glfw.cpp
+++ b/examples/opengl_example/imgui_impl_glfw.cpp
@@ -25,9 +25,6 @@ static GLuint       g_FontTexture = 0;
 // - in your Render function, try translating your projection matrix by (0.5f,0.5f) or (0.375f,0.375f)
 static void ImGui_ImplGlfw_RenderDrawLists(ImDrawList** const cmd_lists, int cmd_lists_count)
 {
-    if (cmd_lists_count == 0)
-        return;
-
     // We are using the OpenGL fixed pipeline to make the example code simpler to read!
     // A probable faster way to render would be to collate all vertices from all cmd_lists into a single vertex buffer.
     // Setup render state: alpha-blending enabled, no face culling, no depth testing, scissor enabled, vertex/texcoord/color pointers.
diff --git a/examples/sdl_opengl_example/imgui_impl_sdl.cpp b/examples/sdl_opengl_example/imgui_impl_sdl.cpp
index b22250b8e..139a5db79 100644
--- a/examples/sdl_opengl_example/imgui_impl_sdl.cpp
+++ b/examples/sdl_opengl_example/imgui_impl_sdl.cpp
@@ -1,3 +1,6 @@
+// ImGui SDL2 binding with OpenGL
+// https://github.com/ocornut/imgui
+
 #include <SDL.h>
 #include <SDL_syswm.h>
 #include <SDL_OpenGL.h>
@@ -52,7 +55,7 @@ static void ImGui_ImplSdl_RenderDrawLists(ImDrawList** const cmd_lists, int cmd_
         glColorPointer(4, GL_UNSIGNED_BYTE, sizeof(ImDrawVert), (void*)(vtx_buffer + OFFSETOF(ImDrawVert, col)));
 
         int vtx_offset = 0;
-        for (size_t cmd_i = 0; cmd_i < cmd_list->commands.size(); cmd_i++)
+        for (int cmd_i = 0; cmd_i < cmd_list->commands.size(); cmd_i++)
         {
             const ImDrawCmd* pcmd = &cmd_list->commands[cmd_i];
             if (pcmd->user_callback)
@@ -63,7 +66,7 @@ static void ImGui_ImplSdl_RenderDrawLists(ImDrawList** const cmd_lists, int cmd_
             {
                 glBindTexture(GL_TEXTURE_2D, (GLuint)(intptr_t)pcmd->texture_id);
                 glScissor((int)pcmd->clip_rect.x, (int)(height - pcmd->clip_rect.w), (int)(pcmd->clip_rect.z - pcmd->clip_rect.x), (int)(pcmd->clip_rect.w - pcmd->clip_rect.y));
-                glDrawArrays(GL_TRIANGLES, vtx_offset, pcmd->vtx_count);
+                glDrawArrays(GL_TRIANGLES, vtx_offset, (GLsizei)pcmd->vtx_count);
             }
             vtx_offset += pcmd->vtx_count;
         }
@@ -117,7 +120,7 @@ bool ImGui_ImplSdl_EventCallback(const SDL_Event& event)
             ImGuiIO& io = ImGui::GetIO();
             unsigned int c = event.text.text[0];
             if (c > 0 && c < 0x10000)
-                io.AddInputCharacter((unsigned short)c);
+                io.AddInputCharacter((unsigned short)event.text.text[0]);
             return true;
         }
     case SDL_KEYDOWN:
@@ -153,6 +156,7 @@ bool ImGui_ImplSdl_CreateDeviceObjects()
     // Store our identifier
     io.Fonts->TexID = (void *)(intptr_t)g_FontTexture;
 
+    // Cleanup (don't clear the input data if you want to append new fonts later)
 	io.Fonts->ClearInputData();
 	io.Fonts->ClearTexData();
 
@@ -224,18 +228,16 @@ void ImGui_ImplSdl_NewFrame(SDL_Window *window)
 	SDL_GetWindowSize(window, &w, &h);
     io.DisplaySize = ImVec2((float)w, (float)h);
 
-	// Time
+    // Setup time step
 	Uint32	time = SDL_GetTicks();
 	double current_time = time / 1000.0;
-
     io.DeltaTime = g_Time > 0.0 ? (float)(current_time - g_Time) : (float)(1.0f/60.0f);
     g_Time = current_time;
 
-	int mx, my;
-	Uint32 mouseMask = SDL_GetMouseState(&mx, &my);
-
     // Setup inputs
     // (we already got mouse wheel, keyboard keys & characters from glfw callbacks polled in glfwPollEvents())
+    int mx, my;
+    Uint32 mouseMask = SDL_GetMouseState(&mx, &my);
     if (SDL_GetWindowFlags(window) & SDL_WINDOW_MOUSE_FOCUS)
     	io.MousePos = ImVec2((float)mx, (float)my);   // Mouse position, in pixels (set to -1,-1 if no mouse / on another screen, etc.)
     else
@@ -249,7 +251,7 @@ void ImGui_ImplSdl_NewFrame(SDL_Window *window)
     io.MouseWheel = g_MouseWheel;
     g_MouseWheel = 0.0f;
 
-    // Hide/show hardware mouse cursor
+    // Hide OS mouse cursor if ImGui is drawing it
     SDL_ShowCursor(io.MouseDrawCursor ? 0 : 1);
 
     // Start the frame
diff --git a/examples/sdl_opengl_example/imgui_impl_sdl.h b/examples/sdl_opengl_example/imgui_impl_sdl.h
index 6d56b2e0e..1e8d91c4b 100644
--- a/examples/sdl_opengl_example/imgui_impl_sdl.h
+++ b/examples/sdl_opengl_example/imgui_impl_sdl.h
@@ -1,3 +1,6 @@
+// ImGui SDL2 binding with OpenGL
+// https://github.com/ocornut/imgui
+
 struct SDL_Window;
 typedef union SDL_Event SDL_Event;
 
@@ -6,5 +9,6 @@ void        ImGui_ImplSdl_Shutdown();
 void        ImGui_ImplSdl_NewFrame(SDL_Window *window);
 bool        ImGui_ImplSdl_EventCallback(const SDL_Event& event);
 
+// Use if you want to reset your rendering device without losing ImGui state.
 void        ImGui_ImplSdl_InvalidateDeviceObjects();
 bool        ImGui_ImplSdl_CreateDeviceObjects();