1
2 // Copyright Marcelo S. N. Mancini(Hipreme) 2020.
3 // Distributed under the Boost Software License, Version 1.0.
4 // (See accompanying file LICENSE_1_0.txt or copy at
5 // http://www.boost.org/LICENSE_1_0.txt)
6
7 module imgui_backend.impl_opengl3;
8 import bindbc.cimgui;
9
10 import std.conv:to;
11 import core.stdc.stdio;
12
13 import core.stdc.string;
14 import core.stdc.stdint : intptr_t;
15
16 /// Whether to use the implementation defined in D or link to compiled ImGui backends instead
17 enum CIMGUI_USER_DEFINED_IMPLEMENTATION_GL = true;
18
19 // dear imgui: Renderer for modern OpenGL with shaders / programmatic pipeline
20 // - Desktop GL: 2.x 3.x 4.x
21 // - Embedded GL: ES 2.0 (WebGL 1.0), ES 3.0 (WebGL 2.0)
22 // This needs to be used along with a Platform Binding (e.g. GLFW, SDL, Win32, custom..)
23
24 // Implemented features:
25 // [X] Renderer: User texture binding. Use 'GLuint' OpenGL texture identifier as void*/ImTextureID. Read the FAQ about ImTextureID!
26 // [x] Renderer: Desktop GL only: Support for large meshes (64k+ vertices) with 16-bit indices.
27
28 // You can copy and use unmodified imgui_impl_* files in your project. See main.cpp for an example of using this.
29 // If you are new to dear imgui, read examples/README.txt and read the documentation at the top of imgui.cpp.
30 // https://github.com/ocornut/imgui
31
32 // CHANGELOG
33 // (minor and older changes stripped away, please see git history for details)
34 // 2020-09-17: OpenGL: Fix to avoid compiling/calling glBindSampler() on ES or pre 3.3 context which have the defines set by a loader.
35 // 2020-07-10: OpenGL: Added support for glad2 OpenGL loader.
36 // 2020-05-08: OpenGL: Made default GLSL version 150 (instead of 130) on OSX.
37 // 2020-04-21: OpenGL: Fixed handling of glClipControl(GL_UPPER_LEFT) by inverting projection matrix.
38 // 2020-04-12: OpenGL: Fixed context version check mistakenly testing for 4.0+ instead of 3.2+ to enable ImGuiBackendFlags_RendererHasVtxOffset.
39 // 2020-03-24: OpenGL: Added support for glbinding 2.x OpenGL loader.
40 // 2020-01-07: OpenGL: Added support for glbinding 3.x OpenGL loader.
41 // 2019-10-25: OpenGL: Using a combination of GL define and runtime GL version to decide whether to use glDrawElementsBaseVertex(). Fix building with pre-3.2 GL loaders.
42 // 2019-09-22: OpenGL: Detect default GL loader using __has_include compiler facility.
43 // 2019-09-16: OpenGL: Tweak initialization code to allow application calling ImGui_ImplOpenGL3_CreateFontsTexture() before the first NewFrame() call.
44 // 2019-05-29: OpenGL: Desktop GL only: Added support for large mesh (64K+ vertices), enable ImGuiBackendFlags_RendererHasVtxOffset flag.
45 // 2019-04-30: OpenGL: Added support for special ImDrawCallback_ResetRenderState callback to reset render state.
46 // 2019-03-29: OpenGL: Not calling glBindBuffer more than necessary in the render loop.
47 // 2019-03-15: OpenGL: Added a GL call + comments in ImGui_ImplOpenGL3_Init() to detect uninitialized GL function loaders early.
48 // 2019-03-03: OpenGL: Fix support for ES 2.0 (WebGL 1.0).
49 // 2019-02-20: OpenGL: Fix for OSX not supporting OpenGL 4.5, we don't try to read GL_CLIP_ORIGIN even if defined by the headers/loader.
50 // 2019-02-11: OpenGL: Projecting clipping rectangles correctly using draw_data.FramebufferScale to allow multi-viewports for retina display.
51 // 2019-02-01: OpenGL: Using GLSL 410 shaders for any version over 410 (e.g. 430, 450).
52 // 2018-11-30: Misc: Setting up io.BackendRendererName so it can be displayed in the About Window.
53 // 2018-11-13: OpenGL: Support for GL 4.5's glClipControl(GL_UPPER_LEFT) / GL_CLIP_ORIGIN.
54 // 2018-08-29: OpenGL: Added support for more OpenGL loaders: glew and glad, with comments indicative that any loader can be used.
55 // 2018-08-09: OpenGL: Default to OpenGL ES 3 on iOS and Android. GLSL version default to "#version 300 ES".
56 // 2018-07-30: OpenGL: Support for GLSL 300 ES and 410 core. Fixes for Emscripten compilation.
57 // 2018-07-10: OpenGL: Support for more GLSL versions (based on the GLSL version string). Added error output when shaders fail to compile/link.
58 // 2018-06-08: Misc: Extracted imgui_impl_opengl3.cpp/.h away from the old combined GLFW/SDL+OpenGL3 examples.
59 // 2018-06-08: OpenGL: Use draw_data.DisplayPos and draw_data.DisplaySize to setup projection matrix and clipping rectangle.
60 // 2018-05-25: OpenGL: Removed unnecessary backup/restore of GL_ELEMENT_ARRAY_BUFFER_BINDING since this is part of the VAO state.
61 // 2018-05-14: OpenGL: Making the call to glBindSampler() optional so 3.2 context won't fail if the function is a null pointer.
62 // 2018-03-06: OpenGL: Added const char* glsl_version parameter to ImGui_ImplOpenGL3_Init() so user can override the GLSL version e.g. "#version 150".
63 // 2018-02-23: OpenGL: Create the VAO in the render function so the setup can more easily be used with multiple shared GL context.
64 // 2018-02-16: Misc: Obsoleted the io.RenderDrawListsFn callback and exposed ImGui_ImplSdlGL3_RenderDrawData() in the .h file so you can call it yourself.
65 // 2018-01-07: OpenGL: Changed GLSL shader version from 330 to 150.
66 // 2017-09-01: OpenGL: Save and restore current bound sampler. Save and restore current polygon mode.
67 // 2017-05-01: OpenGL: Fixed save and restore of current blend func state.
68 // 2017-05-01: OpenGL: Fixed save and restore of current GL_ACTIVE_TEXTURE.
69 // 2016-09-05: OpenGL: Fixed save and restore of current scissor rectangle.
70 // 2016-07-29: OpenGL: Explicitly setting GL_UNPACK_ROW_LENGTH to reduce issues because SDL changes it. (#752)
71
72 //----------------------------------------
73 // OpenGL GLSL GLSL
74 // version version string
75 //----------------------------------------
76 // 2.0 110 "#version 110"
77 // 2.1 120 "#version 120"
78 // 3.0 130 "#version 130"
79 // 3.1 140 "#version 140"
80 // 3.2 150 "#version 150"
81 // 3.3 330 "#version 330 core"
82 // 4.0 400 "#version 400 core"
83 // 4.1 410 "#version 410 core"
84 // 4.2 420 "#version 410 core"
85 // 4.3 430 "#version 430 core"
86 // ES 2.0 100 "#version 100" = WebGL 1.0
87 // ES 3.0 300 "#version 300 es" = WebGL 2.0
88 //----------------------------------------
89
90 // OpenGL version specifiers
91 enum IMGUI_IMPL_OPENGL_ES2 = false;
92 enum GL_VERSION_3_2 = false;
93 enum GL_VERSION_3_3 = false;
94 enum IMGUI_IMPL_OPENGL_ES3 = false;
95
96 enum IMGUI_IMPL_OPENGL_MAY_HAVE_BIND_SAMPLER = false;
97 enum IMGUI_IMPL_OPENGL_MAY_HAVE_VTX_OFFSET = false;
98
99 /// Unused
100 enum _MSC_VER = -1;
101
102 static if(CIMGUI_USER_DEFINED_IMPLEMENTATION_GL)
103 {
104 // GL includes
105 static if(IMGUI_IMPL_OPENGL_ES2)
106 {
107 static assert(0, "This is not yet implemented");
108 }
109 static if(IMGUI_IMPL_OPENGL_ES3)
110 {
111 static assert(0, "This is not yet implemented");
112 }
113 else
114 {
115 import bindbc.opengl;
116 // About Desktop OpenGL function loaders:
117 // Modern desktop OpenGL doesn't have a standard portable header file to load OpenGL function pointers.
118 // Helper libraries are often used for this purpose! Here we are supporting a few common ones (gl3w, glew, glad).
119 // You may use another loader/header of your choice (glext, glLoadGen, etc.), or chose to manually implement your own.
120 // In this case you may also need to change some of this code
121
122 // Desktop GL 3.2+ has glDrawElementsBaseVertex() which GL ES and WebGL don't have.
123 static if(GL_VERSION_3_2)
124 {
125 enum IMGUI_IMPL_OPENGL_MAY_HAVE_VTX_OFFSET = true;
126 }
127 // Desktop GL 3.3+ has glBindSampler()
128 static if(GL_VERSION_3_3)
129 {
130 enum IMGUI_IMPL_OPENGL_MAY_HAVE_BIND_SAMPLER = true;
131 }
132 }
133
134 // OpenGL Data
135 static GLuint g_GlVersion = 0; // Extracted at runtime using GL_MAJOR_VERSION, GL_MINOR_VERSION queries (e.g. 320 for GL 3.2)
136 static char[32] g_GlslVersionString; // Specified by user or detected based on compile time GL settings.
137 static GLuint g_FontTexture = 0;
138 static GLuint g_ShaderHandle = 0, g_VertHandle = 0, g_FragHandle = 0;
139 static GLint g_AttribLocationTex = 0, g_AttribLocationProjMtx = 0; // Uniforms location
140 static GLuint g_AttribLocationVtxPos = 0, g_AttribLocationVtxUV = 0, g_AttribLocationVtxColor = 0; // Vertex attributes location
141 static uint g_VboHandle = 0, g_ElementsHandle = 0;
142
143 // Functions
144 bool ImGui_ImplOpenGL3_Init(const (char)* glsl_version)
145 {
146 // Query for GL version (e.g. 320 for GL 3.2)
147 static if(IMGUI_IMPL_OPENGL_ES2)
148 {
149 g_GlVersion = 200; // GLES 2
150 }
151 else
152 {
153 GLint major, minor;
154 glGetIntegerv(GL_MAJOR_VERSION, &major);
155 glGetIntegerv(GL_MINOR_VERSION, &minor);
156 g_GlVersion = cast(GLuint)(major * 100 + minor * 10);
157 }
158
159
160 // Setup back-end capabilities flags
161 ImGuiIO* io = igGetIO();
162 io.BackendRendererName = "imgui_impl_opengl3";
163 static if(IMGUI_IMPL_OPENGL_MAY_HAVE_VTX_OFFSET)
164 {
165 if (g_GlVersion >= 320)
166 io.BackendFlags |= ImGuiBackendFlags_RendererHasVtxOffset; // We can honor the ImDrawCmd::VtxOffset field, allowing for large meshes.
167 }
168 io.BackendFlags |= ImGuiBackendFlags_RendererHasViewports;
169
170 // Store GLSL version string so we can refer to it later in case we recreate shaders.
171 // Note: GLSL version is NOT the same as GL version. Leave this to null if unsure.
172 static if(IMGUI_IMPL_OPENGL_ES2)
173 {
174 if (glsl_version == "")
175 glsl_version = "#version 100";
176 }
177 static if(IMGUI_IMPL_OPENGL_ES3)
178 {
179 if (glsl_version == "")
180 glsl_version = "#version 300 es";
181 }
182 else
183 {
184 version(__APPLE__)
185 {
186 if (glsl_version == "")
187 glsl_version = "#version 150";
188 }
189 else
190 {
191 if (glsl_version == "")
192 glsl_version = "#version 130";
193 }
194 }
195 import std.conv : to;
196 IM_ASSERT(cast(int)strlen(glsl_version) + 2 < IM_ARRAYSIZE(g_GlslVersionString));
197 strcpy(g_GlslVersionString.ptr, glsl_version);
198 strcat(g_GlslVersionString.ptr, "\n");
199
200 // Debugging construct to make it easily visible in the IDE and debugger which GL loader has been selected.
201 // The code actually never uses the 'gl_loader' variable! It is only here so you can read it!
202 // If auto-detection fails or doesn't select the same GL loader file as used by your application,
203 // you are likely to get a crash below.
204 // You can explicitly select a loader by using '#define IMGUI_IMPL_OPENGL_LOADER_XXX' in imconfig.h or compiler command-line.
205 const (char)* gl_loader = "bindbc-opengl";
206
207 // Make an arbitrary GL call (we don't actually need the result)
208 // IF YOU GET A CRASH HERE: it probably means that you haven't initialized the OpenGL function loader used by this code.
209 // Desktop OpenGL 3/4 need a function loader. See the IMGUI_IMPL_OPENGL_LOADER_xxx explanation above.
210 // Why not just static assert that it is bound?
211 GLint current_texture;
212 glGetIntegerv(GL_TEXTURE_BINDING_2D, ¤t_texture);
213
214 if (io.ConfigFlags & ImGuiConfigFlags_ViewportsEnable)
215 ImGui_ImplOpenGL3_InitPlatformInterface();
216
217 return true;
218 }
219
220 void ImGui_ImplOpenGL3_Shutdown()
221 {
222 ImGui_ImplOpenGL3_ShutdownPlatformInterface();
223 ImGui_ImplOpenGL3_DestroyDeviceObjects();
224 }
225
226 void ImGui_ImplOpenGL3_NewFrame()
227 {
228 if (!g_ShaderHandle)
229 ImGui_ImplOpenGL3_CreateDeviceObjects();
230 }
231
232 static void ImGui_ImplOpenGL3_SetupRenderState(ImDrawData* draw_data, int fb_width, int fb_height, GLuint vertex_array_object)
233 {
234 // Setup render state: alpha-blending enabled, no face culling, no depth testing, scissor enabled, polygon fill
235 glEnable(GL_BLEND);
236 glBlendEquation(GL_FUNC_ADD);
237 glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
238 glDisable(GL_CULL_FACE);
239 glDisable(GL_DEPTH_TEST);
240 glEnable(GL_SCISSOR_TEST);
241 static if(GL_POLYGON_MODE)
242 {
243 glPolygonMode(GL_FRONT_AND_BACK, GL_FILL);
244 }
245
246 // Support for GL 4.5 rarely used glClipControl(GL_UPPER_LEFT)
247 bool clip_origin_lower_left = true;
248 static if (GL_CLIP_ORIGIN)
249 {
250 GLenum current_clip_origin = 0; glGetIntegerv(GL_CLIP_ORIGIN, cast(GLint*)¤t_clip_origin);
251 if (current_clip_origin == GL_UPPER_LEFT)
252 clip_origin_lower_left = false;
253 }
254
255 // Setup viewport, orthographic projection matrix
256 // Our visible imgui space lies from draw_data.DisplayPos (top left) to draw_data.DisplayPos+data_data.DisplaySize (bottom right). DisplayPos is (0,0) for single viewport apps.
257 glViewport(0, 0, cast(GLsizei)fb_width, cast(GLsizei)fb_height);
258 float L = draw_data.DisplayPos.x;
259 float R = draw_data.DisplayPos.x + draw_data.DisplaySize.x;
260 float T = draw_data.DisplayPos.y;
261 float B = draw_data.DisplayPos.y + draw_data.DisplaySize.y;
262 if (!clip_origin_lower_left) { float tmp = T; T = B; B = tmp; } // Swap top and bottom if origin is upper left
263 const float[4][4] ortho_projection =
264 [
265 [ 2.0f/(R-L), 0.0f, 0.0f, 0.0f ],
266 [ 0.0f, 2.0f/(T-B), 0.0f, 0.0f ],
267 [ 0.0f, 0.0f, -1.0f, 0.0f ],
268 [ (R+L)/(L-R), (T+B)/(B-T), 0.0f, 1.0f ],
269 ];
270 glUseProgram(g_ShaderHandle);
271 glUniform1i(g_AttribLocationTex, 0);
272 glUniformMatrix4fv(g_AttribLocationProjMtx, 1, GL_FALSE, &ortho_projection[0][0]);
273
274 static if(IMGUI_IMPL_OPENGL_MAY_HAVE_BIND_SAMPLER)
275 {
276 if (g_GlVersion >= 330)
277 glBindSampler(0, 0); // We use combined texture/sampler state. Applications using GL 3.3 may set that otherwise.
278 }
279 cast(void)vertex_array_object;
280 static if(!IMGUI_IMPL_OPENGL_ES2)
281 {
282 glBindVertexArray(vertex_array_object);
283 }
284
285 // Bind vertex/index buffers and setup attributes for ImDrawVert
286 glBindBuffer(GL_ARRAY_BUFFER, g_VboHandle);
287 glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, g_ElementsHandle);
288 glEnableVertexAttribArray(g_AttribLocationVtxPos);
289 glEnableVertexAttribArray(g_AttribLocationVtxUV);
290 glEnableVertexAttribArray(g_AttribLocationVtxColor);
291 glVertexAttribPointer(g_AttribLocationVtxPos, 2, GL_FLOAT, GL_FALSE, ImDrawVert.sizeof, cast(GLvoid*)IM_OFFSETOF!(ImDrawVert.pos));
292 glVertexAttribPointer(g_AttribLocationVtxUV, 2, GL_FLOAT, GL_FALSE, ImDrawVert.sizeof, cast(GLvoid*)IM_OFFSETOF!(ImDrawVert.uv));
293 glVertexAttribPointer(g_AttribLocationVtxColor, 4, GL_UNSIGNED_BYTE, GL_TRUE, ImDrawVert.sizeof, cast(GLvoid*)IM_OFFSETOF!(ImDrawVert.col));
294 }
295
296 // OpenGL3 Render function.
297 // (this used to be set in io.RenderDrawListsFn and called by ImGui::Render(), but you can now call this directly from your main loop)
298 // Note that this implementation is little overcomplicated because we are saving/setting up/restoring every OpenGL state explicitly, in order to be able to run within any OpenGL engine that doesn't do so.
299 void ImGui_ImplOpenGL3_RenderDrawData(ImDrawData* draw_data)
300 {
301 // Avoid rendering when minimized, scale coordinates for retina displays (screen coordinates != framebuffer coordinates)
302 int fb_width = cast(int)(draw_data.DisplaySize.x * draw_data.FramebufferScale.x);
303 int fb_height = cast(int)(draw_data.DisplaySize.y * draw_data.FramebufferScale.y);
304 if (fb_width <= 0 || fb_height <= 0)
305 return;
306
307 // Backup GL state
308 GLenum last_active_texture; glGetIntegerv(GL_ACTIVE_TEXTURE, cast(GLint*)&last_active_texture);
309 glActiveTexture(GL_TEXTURE0);
310 GLuint last_program; glGetIntegerv(GL_CURRENT_PROGRAM, cast(GLint*)&last_program);
311 GLuint last_texture; glGetIntegerv(GL_TEXTURE_BINDING_2D, cast(GLint*)&last_texture);
312 static if(IMGUI_IMPL_OPENGL_MAY_HAVE_BIND_SAMPLER)
313 {
314 GLuint last_sampler;
315 if (g_GlVersion >= 330)
316 glGetIntegerv(GL_SAMPLER_BINDING, cast(GLint*)&last_sampler);
317 else
318 last_sampler = 0;
319 }
320 GLuint last_array_buffer; glGetIntegerv(GL_ARRAY_BUFFER_BINDING, cast(GLint*)&last_array_buffer);
321 static if(!IMGUI_IMPL_OPENGL_ES2)
322 {
323 GLuint last_vertex_array_object; glGetIntegerv(GL_VERTEX_ARRAY_BINDING, cast(GLint*)&last_vertex_array_object);
324 }
325 static if(GL_POLYGON_MODE)
326 {
327 GLint[2] last_polygon_mode;
328 glGetIntegerv(GL_POLYGON_MODE, &last_polygon_mode[0]);
329 }
330 GLint[4] last_viewport; glGetIntegerv(GL_VIEWPORT, &last_viewport[0]);
331 GLint[4] last_scissor_box; glGetIntegerv(GL_SCISSOR_BOX, &last_scissor_box[0]);
332 GLenum last_blend_src_rgb; glGetIntegerv(GL_BLEND_SRC_RGB, cast(GLint*)&last_blend_src_rgb);
333 GLenum last_blend_dst_rgb; glGetIntegerv(GL_BLEND_DST_RGB, cast(GLint*)&last_blend_dst_rgb);
334 GLenum last_blend_src_alpha; glGetIntegerv(GL_BLEND_SRC_ALPHA, cast(GLint*)&last_blend_src_alpha);
335 GLenum last_blend_dst_alpha; glGetIntegerv(GL_BLEND_DST_ALPHA, cast(GLint*)&last_blend_dst_alpha);
336 GLenum last_blend_equation_rgb; glGetIntegerv(GL_BLEND_EQUATION_RGB, cast(GLint*)&last_blend_equation_rgb);
337 GLenum last_blend_equation_alpha; glGetIntegerv(GL_BLEND_EQUATION_ALPHA, cast(GLint*)&last_blend_equation_alpha);
338 GLboolean last_enable_blend = glIsEnabled(GL_BLEND);
339 GLboolean last_enable_cull_face = glIsEnabled(GL_CULL_FACE);
340 GLboolean last_enable_depth_test = glIsEnabled(GL_DEPTH_TEST);
341 GLboolean last_enable_scissor_test = glIsEnabled(GL_SCISSOR_TEST);
342
343 // Setup desired GL state
344 // Recreate the VAO every time (this is to easily allow multiple GL contexts to be rendered to. VAO are not shared among GL contexts)
345 // The renderer would actually work without any VAO bound, but then our VertexAttrib calls would overwrite the default one currently bound.
346 GLuint vertex_array_object = 0;
347 static if(!IMGUI_IMPL_OPENGL_ES2)
348 {
349 glGenVertexArrays(1, &vertex_array_object);
350 }
351 ImGui_ImplOpenGL3_SetupRenderState(draw_data, fb_width, fb_height, vertex_array_object);
352
353 // Will project scissor/clipping rectangles into framebuffer space
354 ImVec2 clip_off = draw_data.DisplayPos; // (0,0) unless using multi-viewports
355 ImVec2 clip_scale = draw_data.FramebufferScale; // (1,1) unless using retina display which are often (2,2)
356
357 // Render command lists
358 for (int n = 0; n < draw_data.CmdListsCount; n++)
359 {
360 ImDrawList* cmd_list = draw_data.CmdLists[n]; //Const was there
361
362 // Upload vertex/index buffers
363 glBufferData(GL_ARRAY_BUFFER, cast(GLsizeiptr)cmd_list.VtxBuffer.Size * cast(int)ImDrawVert.sizeof, cast(const GLvoid*)cmd_list.VtxBuffer.Data, GL_STREAM_DRAW);
364 glBufferData(GL_ELEMENT_ARRAY_BUFFER, cast(GLsizeiptr)cmd_list.IdxBuffer.Size * cast(int)ImDrawIdx.sizeof, cast(const GLvoid*)cmd_list.IdxBuffer.Data, GL_STREAM_DRAW);
365
366 for (int cmd_i = 0; cmd_i < cmd_list.CmdBuffer.Size; cmd_i++)
367 {
368 const (ImDrawCmd)* pcmd = &(cmd_list.CmdBuffer.Data[cmd_i]);
369 if (pcmd.UserCallback != null)
370 {
371 // User callback, registered via ImDrawList::AddCallback()
372 // (ImDrawCallback_ResetRenderState is a special callback value used by the user to request the renderer to reset render state.)
373 if (pcmd.UserCallback == ImDrawCallback_ResetRenderState)
374 ImGui_ImplOpenGL3_SetupRenderState(draw_data, fb_width, fb_height, vertex_array_object);
375 else
376 pcmd.UserCallback(cmd_list, pcmd);
377 }
378 else
379 {
380 // Project scissor/clipping rectangles into framebuffer space
381 ImVec4 clip_rect;
382 clip_rect.x = (pcmd.ClipRect.x - clip_off.x) * clip_scale.x;
383 clip_rect.y = (pcmd.ClipRect.y - clip_off.y) * clip_scale.y;
384 clip_rect.z = (pcmd.ClipRect.z - clip_off.x) * clip_scale.x;
385 clip_rect.w = (pcmd.ClipRect.w - clip_off.y) * clip_scale.y;
386
387 if (clip_rect.x < fb_width && clip_rect.y < fb_height && clip_rect.z >= 0.0f && clip_rect.w >= 0.0f)
388 {
389 // Apply scissor/clipping rectangle
390 glScissor(cast(int)clip_rect.x, cast(int)(fb_height - clip_rect.w), cast(int)(clip_rect.z - clip_rect.x), cast(int)(clip_rect.w - clip_rect.y));
391
392 // Bind texture, Draw
393 glBindTexture(GL_TEXTURE_2D, cast(GLuint)cast(intptr_t)pcmd.TextureId);
394 static if(IMGUI_IMPL_OPENGL_MAY_HAVE_VTX_OFFSET)
395 {
396 if (g_GlVersion >= 320)
397 glDrawElementsBaseVertex(GL_TRIANGLES, cast(GLsizei)pcmd.ElemCount, ImDrawIdx.sizeof == 2 ? GL_UNSIGNED_SHORT : GL_UNSIGNED_INT, cast(void*)cast(intptr_t)(pcmd.IdxOffset * ImDrawIdx.sizeof), cast(GLint)pcmd.VtxOffset);
398 }
399 //If not drawelement base vertex
400 glDrawElements(GL_TRIANGLES, cast(GLsizei)pcmd.ElemCount, ImDrawIdx.sizeof == 2 ? GL_UNSIGNED_SHORT : GL_UNSIGNED_INT, cast(void*)cast(intptr_t)(pcmd.IdxOffset * ImDrawIdx.sizeof));
401 }
402 }
403 }
404 }
405
406 // Destroy the temporary VAO
407 static if(!IMGUI_IMPL_OPENGL_ES2)
408 {
409 glDeleteVertexArrays(1, &vertex_array_object);
410 }
411
412 // Restore modified GL state
413 glUseProgram(last_program);
414 glBindTexture(GL_TEXTURE_2D, last_texture);
415 static if(IMGUI_IMPL_OPENGL_MAY_HAVE_BIND_SAMPLER)
416 {
417 if (g_GlVersion >= 330)
418 glBindSampler(0, last_sampler);
419 }
420 glActiveTexture(last_active_texture);
421 static if(!IMGUI_IMPL_OPENGL_ES2)
422 {
423 glBindVertexArray(last_vertex_array_object);
424 }
425 glBindBuffer(GL_ARRAY_BUFFER, last_array_buffer);
426 glBlendEquationSeparate(last_blend_equation_rgb, last_blend_equation_alpha);
427 glBlendFuncSeparate(last_blend_src_rgb, last_blend_dst_rgb, last_blend_src_alpha, last_blend_dst_alpha);
428 if (last_enable_blend) glEnable(GL_BLEND); else glDisable(GL_BLEND);
429 if (last_enable_cull_face) glEnable(GL_CULL_FACE); else glDisable(GL_CULL_FACE);
430 if (last_enable_depth_test) glEnable(GL_DEPTH_TEST); else glDisable(GL_DEPTH_TEST);
431 if (last_enable_scissor_test) glEnable(GL_SCISSOR_TEST); else glDisable(GL_SCISSOR_TEST);
432 static if(GL_POLYGON_MODE)
433 {
434 glPolygonMode(GL_FRONT_AND_BACK, cast(GLenum)last_polygon_mode[0]);
435 }
436 glViewport(last_viewport[0], last_viewport[1], cast(GLsizei)last_viewport[2], cast(GLsizei)last_viewport[3]);
437 glScissor(last_scissor_box[0], last_scissor_box[1], cast(GLsizei)last_scissor_box[2], cast(GLsizei)last_scissor_box[3]);
438 }
439
440 bool ImGui_ImplOpenGL3_CreateFontsTexture()
441 {
442 // Build texture atlas
443 ImGuiIO* io = igGetIO();
444 ubyte* pixels = null;
445 int width, height;
446 static int bytePerPixel = 4;
447
448 ImFontAtlas_GetTexDataAsRGBA32(io.Fonts, &pixels, &width, &height, &bytePerPixel); // Load as RGBA 32-bit (75% of the memory is wasted, but default font is so small) because it is more likely to be compatible with user's existing shaders. If your ImTextureId represent a higher-level concept than just a GL texture id, consider calling GetTexDataAsAlpha8() instead to save on GPU memory.
449
450 import std.stdio;
451 // Upload texture to graphics system
452 GLint last_texture;
453 glGetIntegerv(GL_TEXTURE_BINDING_2D, &last_texture);
454 glGenTextures(1, &g_FontTexture);
455 glBindTexture(GL_TEXTURE_2D, g_FontTexture);
456 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
457 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
458 static if(GL_UNPACK_ROW_LENGTH)
459 {
460 glPixelStorei(GL_UNPACK_ROW_LENGTH, 0);
461 }
462 glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, width, height, 0, GL_RGBA, GL_UNSIGNED_BYTE, pixels);
463
464 // Store our identifier
465 io.Fonts.TexID = cast(ImTextureID)cast(intptr_t)g_FontTexture;
466
467 // Restore state
468 glBindTexture(GL_TEXTURE_2D, last_texture);
469
470 return true;
471 }
472
473 void ImGui_ImplOpenGL3_DestroyFontsTexture()
474 {
475 if (g_FontTexture)
476 {
477 ImGuiIO* io = igGetIO();
478 glDeleteTextures(1, &g_FontTexture);
479 io.Fonts.TexID = null; //Same as 0
480 g_FontTexture = 0;
481 }
482 }
483
484 // If you get an error please report on github. You may try different GL context version or GLSL version. See GL<>GLSL version table at the top of this file.
485 static bool CheckShader(GLuint handle, const (char)* desc)
486 {
487 GLint status = 0, log_length = 0;
488 glGetShaderiv(handle, GL_COMPILE_STATUS, &status);
489 glGetShaderiv(handle, GL_INFO_LOG_LENGTH, &log_length);
490
491 if (cast(GLboolean)status == GL_FALSE)
492 fprintf(stderr, "ERROR: ImGui_ImplOpenGL3_CreateDeviceObjects: failed to compile %s!\n", desc);
493 if (log_length > 1)
494 {
495
496 // ImVector_char buf;
497 // buf.resize(cast(int)(log_length + 1));
498 // glGetShaderInfoLog(handle, log_length, null, cast(GLchar*)buf.begin());
499 // fprintf(stderr, "%s\n", buf.begin());
500 }
501 return cast(GLboolean)status == GL_TRUE;
502 }
503
504 // If you get an error please report on GitHub. You may try different GL context version or GLSL version.
505 static bool CheckProgram(GLuint handle, const (char)* desc)
506 {
507 GLint status = 0, log_length = 0;
508 glGetProgramiv(handle, GL_LINK_STATUS, &status);
509 glGetProgramiv(handle, GL_INFO_LOG_LENGTH, &log_length);
510 if (cast(GLboolean)status == GL_FALSE)
511 fprintf(stderr, "ERROR: ImGui_ImplOpenGL3_CreateDeviceObjects: failed to link %s! (with GLSL '%s')\n", desc, &g_GlslVersionString[0]);
512 if (log_length > 1)
513 {
514 // ImVector_char buf;
515 // buf.resize(cast(int)(log_length + 1));
516 // glGetProgramInfoLog(handle, log_length, null, cast(GLchar*)buf.begin());
517 // fprintf(stderr, "%s\n", buf.begin());
518 }
519 return cast(GLboolean)status == GL_TRUE;
520 }
521
522 bool ImGui_ImplOpenGL3_CreateDeviceObjects()
523 {
524 // Backup GL state
525 GLint last_texture, last_array_buffer;
526 glGetIntegerv(GL_TEXTURE_BINDING_2D, &last_texture);
527 glGetIntegerv(GL_ARRAY_BUFFER_BINDING, &last_array_buffer);
528 static if(!IMGUI_IMPL_OPENGL_ES2)
529 {
530 GLint last_vertex_array;
531 glGetIntegerv(GL_VERTEX_ARRAY_BINDING, &last_vertex_array);
532 }
533
534
535
536 // Parse GLSL version string
537 int glsl_version = 130;
538 sscanf(&g_GlslVersionString[0], "#version %d", &glsl_version);
539
540 const (GLchar)* vertex_shader_glsl_120 =
541 "uniform mat4 ProjMtx;\n"~
542 "attribute vec2 Position;\n"~
543 "attribute vec2 UV;\n"~
544 "attribute vec4 Color;\n"~
545 "varying vec2 Frag_UV;\n"~
546 "varying vec4 Frag_Color;\n"~
547 "void main()\n"~
548 "{\n"~
549 " Frag_UV = UV;\n"~
550 " Frag_Color = Color;\n"~
551 " gl_Position = ProjMtx * vec4(Position.xy,0,1);\n"~
552 "}\n";
553
554 const (GLchar)* vertex_shader_glsl_130 =
555 "uniform mat4 ProjMtx;\n"~
556 "in vec2 Position;\n"~
557 "in vec2 UV;\n"~
558 "in vec4 Color;\n"~
559 "out vec2 Frag_UV;\n"~
560 "out vec4 Frag_Color;\n"~
561 "void main()\n"~
562 "{\n"~
563 " Frag_UV = UV;\n"~
564 " Frag_Color = Color;\n"~
565 " gl_Position = ProjMtx * vec4(Position.xy,0,1);\n"~
566 "}\n";
567
568 const (GLchar)* vertex_shader_glsl_300_es =
569 "precision mediump float;\n"~
570 "layout (location = 0) in vec2 Position;\n"~
571 "layout (location = 1) in vec2 UV;\n"~
572 "layout (location = 2) in vec4 Color;\n"~
573 "uniform mat4 ProjMtx;\n"~
574 "out vec2 Frag_UV;\n"~
575 "out vec4 Frag_Color;\n"~
576 "void main()\n"~
577 "{\n"~
578 " Frag_UV = UV;\n"~
579 " Frag_Color = Color;\n"~
580 " gl_Position = ProjMtx * vec4(Position.xy,0,1);\n"~
581 "}\n";
582
583 const (GLchar)* vertex_shader_glsl_410_core =
584 "layout (location = 0) in vec2 Position;\n"~
585 "layout (location = 1) in vec2 UV;\n"~
586 "layout (location = 2) in vec4 Color;\n"~
587 "uniform mat4 ProjMtx;\n"~
588 "out vec2 Frag_UV;\n"~
589 "out vec4 Frag_Color;\n"~
590 "void main()\n"~
591 "{\n"~
592 " Frag_UV = UV;\n"~
593 " Frag_Color = Color;\n"~
594 " gl_Position = ProjMtx * vec4(Position.xy,0,1);\n"~
595 "}\n";
596
597 const (GLchar)* fragment_shader_glsl_120 =
598 "#ifdef GL_ES\n"~
599 " precision mediump float;\n"~
600 "#endif\n"~
601 "uniform sampler2D Texture;\n"~
602 "varying vec2 Frag_UV;\n"~
603 "varying vec4 Frag_Color;\n"~
604 "void main()\n"~
605 "{\n"~
606 " gl_FragColor = Frag_Color * texture2D(Texture, Frag_UV.st);\n"~
607 "}\n";
608
609 const (GLchar)* fragment_shader_glsl_130 =
610 "uniform sampler2D Texture;\n"~
611 "in vec2 Frag_UV;\n"~
612 "in vec4 Frag_Color;\n"~
613 "out vec4 Out_Color;\n"~
614 "void main()\n"~
615 "{\n"~
616 " Out_Color = Frag_Color * texture(Texture, Frag_UV.st);\n"~
617 "}\n";
618
619 const (GLchar)* fragment_shader_glsl_300_es =
620 "precision mediump float;\n"~
621 "uniform sampler2D Texture;\n"~
622 "in vec2 Frag_UV;\n"~
623 "in vec4 Frag_Color;\n"~
624 "layout (location = 0) out vec4 Out_Color;\n"~
625 "void main()\n"~
626 "{\n"~
627 " Out_Color = Frag_Color * texture(Texture, Frag_UV.st);\n"~
628 "}\n";
629
630 const (GLchar)* fragment_shader_glsl_410_core =
631 "in vec2 Frag_UV;\n"~
632 "in vec4 Frag_Color;\n"~
633 "uniform sampler2D Texture;\n"~
634 "layout (location = 0) out vec4 Out_Color;\n"~
635 "void main()\n"~
636 "{\n"~
637 " Out_Color = Frag_Color * texture(Texture, Frag_UV.st);\n"~
638 "}\n";
639
640 // Select shaders matching our GLSL versions
641 const (GLchar)* vertex_shader = null;
642 const (GLchar)* fragment_shader = null;
643 if (glsl_version < 130)
644 {
645 vertex_shader = vertex_shader_glsl_120;
646 fragment_shader = fragment_shader_glsl_120;
647 }
648 else if (glsl_version >= 410)
649 {
650 vertex_shader = vertex_shader_glsl_410_core;
651 fragment_shader = fragment_shader_glsl_410_core;
652 }
653 else if (glsl_version == 300)
654 {
655 vertex_shader = vertex_shader_glsl_300_es;
656 fragment_shader = fragment_shader_glsl_300_es;
657 }
658 else
659 {
660 vertex_shader = vertex_shader_glsl_130;
661 fragment_shader = fragment_shader_glsl_130;
662 }
663
664 // Create shaders
665 const (GLchar)*[2] vertex_shader_with_version = [g_GlslVersionString.ptr, vertex_shader ];
666 g_VertHandle = glCreateShader(GL_VERTEX_SHADER);
667 glShaderSource(g_VertHandle, 2, vertex_shader_with_version.ptr, null);
668 glCompileShader(g_VertHandle);
669 CheckShader(g_VertHandle, "vertex shader");
670
671 const (GLchar)*[2] fragment_shader_with_version = [g_GlslVersionString.ptr, fragment_shader];
672 g_FragHandle = glCreateShader(GL_FRAGMENT_SHADER);
673 glShaderSource(g_FragHandle, 2, fragment_shader_with_version.ptr, null);
674 glCompileShader(g_FragHandle);
675 CheckShader(g_FragHandle, "fragment shader");
676
677 g_ShaderHandle = glCreateProgram();
678 glAttachShader(g_ShaderHandle, g_VertHandle);
679 glAttachShader(g_ShaderHandle, g_FragHandle);
680 glLinkProgram(g_ShaderHandle);
681 CheckProgram(g_ShaderHandle, "shader program");
682
683 g_AttribLocationTex = glGetUniformLocation(g_ShaderHandle, "Texture");
684 g_AttribLocationProjMtx = glGetUniformLocation(g_ShaderHandle, "ProjMtx");
685 g_AttribLocationVtxPos = cast(GLuint)glGetAttribLocation(g_ShaderHandle, "Position");
686 g_AttribLocationVtxUV = cast(GLuint)glGetAttribLocation(g_ShaderHandle, "UV");
687 g_AttribLocationVtxColor = cast(GLuint)glGetAttribLocation(g_ShaderHandle, "Color");
688
689 // Create buffers
690 glGenBuffers(1, &g_VboHandle);
691 glGenBuffers(1, &g_ElementsHandle);
692
693 ImGui_ImplOpenGL3_CreateFontsTexture();
694
695 // Restore modified GL state
696 glBindTexture(GL_TEXTURE_2D, last_texture);
697 glBindBuffer(GL_ARRAY_BUFFER, last_array_buffer);
698 static if(!IMGUI_IMPL_OPENGL_ES2)
699 {
700 glBindVertexArray(last_vertex_array);
701 }
702
703 return true;
704 }
705
706 void ImGui_ImplOpenGL3_DestroyDeviceObjects()
707 {
708 if (g_VboHandle) { glDeleteBuffers(1, &g_VboHandle); g_VboHandle = 0; }
709 if (g_ElementsHandle) { glDeleteBuffers(1, &g_ElementsHandle); g_ElementsHandle = 0; }
710 if (g_ShaderHandle && g_VertHandle) { glDetachShader(g_ShaderHandle, g_VertHandle); }
711 if (g_ShaderHandle && g_FragHandle) { glDetachShader(g_ShaderHandle, g_FragHandle); }
712 if (g_VertHandle) { glDeleteShader(g_VertHandle); g_VertHandle = 0; }
713 if (g_FragHandle) { glDeleteShader(g_FragHandle); g_FragHandle = 0; }
714 if (g_ShaderHandle) { glDeleteProgram(g_ShaderHandle); g_ShaderHandle = 0; }
715
716 ImGui_ImplOpenGL3_DestroyFontsTexture();
717 }
718
719
720 //--------------------------------------------------------------------------------------------------------
721 // MULTI-VIEWPORT / PLATFORM INTERFACE SUPPORT
722 // This is an _advanced_ and _optional_ feature, allowing the back-end to create and handle multiple viewports simultaneously.
723 // If you are new to dear imgui or creating a new binding for dear imgui, it is recommended that you completely ignore this section first..
724 //--------------------------------------------------------------------------------------------------------
725
726 extern(C++) static void ImGui_ImplOpenGL3_RenderWindow(ImGuiViewport* viewport, void*)
727 {
728 //viewport = cast(ImGuiViewport*)param;
729 if (!(viewport.Flags & ImGuiViewportFlags_NoRendererClear))
730 {
731 ImVec4 clear_color = ImVec4(0.0f, 0.0f, 0.0f, 1.0f);
732 glClearColor(clear_color.x, clear_color.y, clear_color.z, clear_color.w);
733 glClear(GL_COLOR_BUFFER_BIT);
734 }
735 ImGui_ImplOpenGL3_RenderDrawData(viewport.DrawData);
736 }
737
738 static void ImGui_ImplOpenGL3_InitPlatformInterface()
739 {
740 ImGuiPlatformIO* platform_io = igGetPlatformIO();
741 platform_io.Renderer_RenderWindow = &ImGui_ImplOpenGL3_RenderWindow;
742 }
743
744 static void ImGui_ImplOpenGL3_ShutdownPlatformInterface()
745 {
746 igDestroyPlatformWindows();
747 }
748
749 }
750 else
751 {
752 extern(C) @nogc nothrow
753 {
754 alias pImGui_ImplOpenGL3_Init = bool function(const (char)* glsl_version);
755 alias pImGui_ImplOpenGL3_Shutdown = void function();
756 alias pImGui_ImplOpenGL3_NewFrame = void function();
757 alias pImGui_ImplOpenGL3_RenderDrawData = void function(ImDrawData* draw_data);
758 alias pImGui_ImplOpenGL3_CreateFontsTexture = bool function();
759 alias pImGui_ImplOpenGL3_DestroyFontsTexture = void function();
760 alias pImGui_ImplOpenGL3_CreateDeviceObjects = bool function();
761 alias pImGui_ImplOpenGL3_DestroyDeviceObjects = void function();
762 }
763
764 __gshared
765 {
766 pImGui_ImplOpenGL3_Init ImGui_ImplOpenGL3_Init;
767 pImGui_ImplOpenGL3_Shutdown ImGui_ImplOpenGL3_Shutdown;
768 pImGui_ImplOpenGL3_NewFrame ImGui_ImplOpenGL3_NewFrame;
769 pImGui_ImplOpenGL3_RenderDrawData ImGui_ImplOpenGL3_RenderDrawData;
770 pImGui_ImplOpenGL3_CreateFontsTexture ImGui_ImplOpenGL3_CreateFontsTexture;
771 pImGui_ImplOpenGL3_DestroyFontsTexture ImGui_ImplOpenGL3_DestroyFontsTexture;
772 pImGui_ImplOpenGL3_CreateDeviceObjects ImGui_ImplOpenGL3_CreateDeviceObjects;
773 pImGui_ImplOpenGL3_DestroyDeviceObjects ImGui_ImplOpenGL3_DestroyDeviceObjects;
774 }
775 import bindbc.loader:SharedLib, bindSymbol;
776 void bindGLImgui(SharedLib lib)
777 {
778 lib.bindSymbol(cast(void**)&ImGui_ImplOpenGL3_Init, "ImGui_ImplOpenGL3_Init");
779 lib.bindSymbol(cast(void**)&ImGui_ImplOpenGL3_Shutdown, "ImGui_ImplOpenGL3_Shutdown");
780 lib.bindSymbol(cast(void**)&ImGui_ImplOpenGL3_NewFrame, "ImGui_ImplOpenGL3_NewFrame");
781 lib.bindSymbol(cast(void**)&ImGui_ImplOpenGL3_RenderDrawData, "ImGui_ImplOpenGL3_RenderDrawData");
782 lib.bindSymbol(cast(void**)&ImGui_ImplOpenGL3_CreateFontsTexture, "ImGui_ImplOpenGL3_CreateFontsTexture");
783 lib.bindSymbol(cast(void**)&ImGui_ImplOpenGL3_DestroyFontsTexture, "ImGui_ImplOpenGL3_DestroyFontsTexture");
784 lib.bindSymbol(cast(void**)&ImGui_ImplOpenGL3_CreateDeviceObjects, "ImGui_ImplOpenGL3_CreateDeviceObjects");
785 lib.bindSymbol(cast(void**)&ImGui_ImplOpenGL3_DestroyDeviceObjects, "ImGui_ImplOpenGL3_DestroyDeviceObjects");
786 }
787 }