1111#include < stdio.h>
1212#include < GLFW/glfw3.h>
1313
14+ #ifdef __EMSCRIPTEN__
15+ #include < emscripten.h>
16+ #endif
17+
1418static void glfw_error_callback (int error, const char * description)
1519{
1620 fprintf (stderr, " Error %d: %s\n "
1721}
1822
23+ // Global variables nedded for step() method implementation
24+ static GLFWwindow* window;
25+ static bool show_demo_window;
26+ static bool show_another_window;
27+ static ImVec4 clear_color;
28+
29+ void step ();
30+
1931int main (int , char **)
2032{
2133 // Setup window
2234 glfwSetErrorCallback (glfw_error_callback);
2335 if (!glfwInit ())
2436 return 1 ;
25- GLFWwindow* window = glfwCreateWindow (1280 , 720 , " ImGui GLFW+OpenGL2 example" NULL , NULL );
37+ window = glfwCreateWindow (1280 , 720 , " ImGui GLFW+OpenGL2 example" NULL , NULL );
2638 glfwMakeContextCurrent (window);
39+ #ifndef __EMSCRIPTEN__
2740 glfwSwapInterval (1 ); // Enable vsync
41+ #endif
2842
2943 // Setup ImGui binding
3044 ImGui::CreateContext ();
@@ -51,68 +65,20 @@ int main(int, char**)
5165 // ImFont* font = io.Fonts->AddFontFromFileTTF("c:\\Windows\\Fonts\\ArialUni.ttf", 18.0f, NULL, io.Fonts->GetGlyphRangesJapanese());
5266 // IM_ASSERT(font != NULL);
5367
54- bool show_demo_window = true ;
55- bool show_another_window = false ;
56- ImVec4 clear_color = ImVec4 (0 .45f , 0 .55f , 0 .60f , 1 .00f );
68+ // Default values
69+ show_demo_window = true ;
70+ show_another_window = false ;
71+ clear_color = ImVec4 (0 .45f , 0 .55f , 0 .60f , 1 .00f );
5772
5873 // Main loop
74+ #ifdef __EMSCRIPTEN__
75+ emscripten_set_main_loop (step, 0 , 1 );
76+ #else
5977 while (!glfwWindowShouldClose (window))
6078 {
61- // You can read the io.WantCaptureMouse, io.WantCaptureKeyboard flags to tell if dear imgui wants to use your inputs.
62- // - When io.WantCaptureMouse is true, do not dispatch mouse input data to your main application.
63- // - When io.WantCaptureKeyboard is true, do not dispatch keyboard input data to your main application.
64- // Generally you may always pass all inputs to dear imgui, and hide them from your application based on those two flags.
65- glfwPollEvents ();
66- ImGui_ImplGlfwGL2_NewFrame ();
67-
68- // 1. Show a simple window.
69- // Tip: if we don't call ImGui::Begin()/ImGui::End() the widgets automatically appears in a window called "Debug".
70- {
71- static float f = 0 .0f ;
72- static int counter = 0 ;
73- ImGui::Text (" Hello, world!" // Display some text (you can use a format string too)
74- ImGui::SliderFloat (" float" 0 .0f , 1 .0f ); // Edit 1 float using a slider from 0.0f to 1.0f
75- ImGui::ColorEdit3 (" clear color" float *)&clear_color); // Edit 3 floats representing a color
76-
77- ImGui::Checkbox (" Demo Window" // Edit bools storing our windows open/close state
78- ImGui::Checkbox (" Another Window"
79-
80- if (ImGui::Button (" Button" // Buttons return true when clicked (NB: most widgets return true when edited/activated)
81- counter++;
82- ImGui::SameLine ();
83- ImGui::Text (" counter = %d"
84-
85- ImGui::Text (" Application average %.3f ms/frame (%.1f FPS)" 1000 .0f / ImGui::GetIO ().Framerate , ImGui::GetIO ().Framerate );
86- }
87-
88- // 2. Show another simple window. In most cases you will use an explicit Begin/End pair to name your windows.
89- if (show_another_window)
90- {
91- ImGui::Begin (" Another Window"
92- ImGui::Text (" Hello from another window!"
93- if (ImGui::Button (" Close Me"
94- show_another_window = false ;
95- ImGui::End ();
96- }
97-
98- // 3. Show the ImGui demo window. Most of the sample code is in ImGui::ShowDemoWindow(). Read its code to learn more about Dear ImGui!
99- if (show_demo_window)
100- {
101- ImGui::SetNextWindowPos (ImVec2 (650 , 20 ), ImGuiCond_FirstUseEver); // Normally user code doesn't need/want to call this because positions are saved in .ini file anyway. Here we just want to make the demo initial state a bit more friendly!
102- ImGui::ShowDemoWindow (&show_demo_window);
103- }
104-
105- // Rendering
106- int display_w, display_h;
107- glfwGetFramebufferSize (window, &display_w, &display_h);
108- glViewport (0 , 0 , display_w, display_h);
109- glClearColor (clear_color.x , clear_color.y , clear_color.z , clear_color.w );
110- glClear (GL_COLOR_BUFFER_BIT);
111- // glUseProgram(0); // You may want this if using this code in an OpenGL 3+ context where shaders may be bound, but prefer using the GL3+ code.
112- ImGui::Render ();
113- ImGui_ImplGlfwGL2_RenderDrawData (ImGui::GetDrawData ());
114- glfwSwapBuffers (window);
79+ step ();
11580 }
81+ #endif
11682
11783 // Cleanup
11884 ImGui_ImplGlfwGL2_Shutdown ();
@@ -121,3 +87,61 @@ int main(int, char**)
12187
12288 return 0 ;
12389}
90+
91+ void step ()
92+ {
93+ // You can read the io.WantCaptureMouse, io.WantCaptureKeyboard flags to tell if dear imgui wants to use your inputs.
94+ // - When io.WantCaptureMouse is true, do not dispatch mouse input data to your main application.
95+ // - When io.WantCaptureKeyboard is true, do not dispatch keyboard input data to your main application.
96+ // Generally you may always pass all inputs to dear imgui, and hide them from your application based on those two flags.
97+ glfwPollEvents ();
98+ ImGui_ImplGlfwGL2_NewFrame ();
99+
100+ // 1. Show a simple window.
101+ // Tip: if we don't call ImGui::Begin()/ImGui::End() the widgets automatically appears in a window called "Debug".
102+ {
103+ static float f = 0 .0f ;
104+ static int counter = 0 ;
105+ ImGui::Text (" Hello, world!" // Display some text (you can use a format string too)
106+ ImGui::SliderFloat (" float" 0 .0f , 1 .0f ); // Edit 1 float using a slider from 0.0f to 1.0f
107+ ImGui::ColorEdit3 (" clear color" float *)&clear_color); // Edit 3 floats representing a color
108+
109+ ImGui::Checkbox (" Demo Window" // Edit bools storing our windows open/close state
110+ ImGui::Checkbox (" Another Window"
111+
112+ if (ImGui::Button (" Button" // Buttons return true when clicked (NB: most widgets return true when edited/activated)
113+ counter++;
114+ ImGui::SameLine ();
115+ ImGui::Text (" counter = %d"
116+
117+ ImGui::Text (" Application average %.3f ms/frame (%.1f FPS)" 1000 .0f / ImGui::GetIO ().Framerate , ImGui::GetIO ().Framerate );
118+ }
119+
120+ // 2. Show another simple window. In most cases you will use an explicit Begin/End pair to name your windows.
121+ if (show_another_window)
122+ {
123+ ImGui::Begin (" Another Window"
124+ ImGui::Text (" Hello from another window!"
125+ if (ImGui::Button (" Close Me"
126+ show_another_window = false ;
127+ ImGui::End ();
128+ }
129+
130+ // 3. Show the ImGui demo window. Most of the sample code is in ImGui::ShowDemoWindow(). Read its code to learn more about Dear ImGui!
131+ if (show_demo_window)
132+ {
133+ ImGui::SetNextWindowPos (ImVec2 (650 , 20 ), ImGuiCond_FirstUseEver); // Normally user code doesn't need/want to call this because positions are saved in .ini file anyway. Here we just want to make the demo initial state a bit more friendly!
134+ ImGui::ShowDemoWindow (&show_demo_window);
135+ }
136+
137+ // Rendering
138+ int display_w, display_h;
139+ glfwGetFramebufferSize (window, &display_w, &display_h);
140+ glViewport (0 , 0 , display_w, display_h);
141+ glClearColor (clear_color.x , clear_color.y , clear_color.z , clear_color.w );
142+ glClear (GL_COLOR_BUFFER_BIT);
143+ // glUseProgram(0); // You may want this if using this code in an OpenGL 3+ context where shaders may be bound, but prefer using the GL3+ code.
144+ ImGui::Render ();
145+ ImGui_ImplGlfwGL2_RenderDrawData (ImGui::GetDrawData ());
146+ glfwSwapBuffers (window);
147+ }
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