Backends: OpenGL2, OpenGL3: Backup and restore GL_SHADE_MODAL, GL_STENCIL_TEST, clear GL_NORMAL_ARRAY. Comments., (#3671, #3668)

This commit is contained in:
ocornut
2021-01-03 15:55:12 +01:00
parent 0a5f399805
commit 7d5d5711c2
4 changed files with 30 additions and 14 deletions

View File

@ -18,7 +18,8 @@
// CHANGELOG
// (minor and older changes stripped away, please see git history for details)
// 2020-01-23: OpenGL: Explicitly backup, setup and restore GL_TEXTURE_ENV to increase compatibility with legacy OpenGL applications.
// 2021-01-03: OpenGL: Backup, setup and restore GL_SHADE_MODAL state, disable GL_STENCIL_TEST and disable GL_NORMAL_ARRAY client state to increase compatibility with legacy OpenGL applications.
// 2020-01-23: OpenGL: Backup, setup and restore GL_TEXTURE_ENV to increase compatibility with legacy OpenGL applications.
// 2019-04-30: OpenGL: Added support for special ImDrawCallback_ResetRenderState callback to reset render state.
// 2019-02-11: OpenGL: Projecting clipping rectangles correctly using draw_data->FramebufferScale to allow multi-viewports for retina display.
// 2018-11-30: Misc: Setting up io.BackendRendererName so it can be displayed in the About Window.
@ -82,23 +83,29 @@ static void ImGui_ImplOpenGL2_SetupRenderState(ImDrawData* draw_data, int fb_wid
glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
glDisable(GL_CULL_FACE);
glDisable(GL_DEPTH_TEST);
glDisable(GL_STENCIL_TEST);
glDisable(GL_LIGHTING);
glDisable(GL_COLOR_MATERIAL);
glEnable(GL_SCISSOR_TEST);
glEnableClientState(GL_VERTEX_ARRAY);
glEnableClientState(GL_TEXTURE_COORD_ARRAY);
glEnableClientState(GL_COLOR_ARRAY);
glDisableClientState(GL_NORMAL_ARRAY);
glEnable(GL_TEXTURE_2D);
glPolygonMode(GL_FRONT_AND_BACK, GL_FILL);
glShadeModel(GL_SMOOTH);
glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);
// If you are using this code with non-legacy OpenGL header/contexts (which you should not, prefer using imgui_impl_opengl3.cpp!!),
// you may need to backup/reset/restore current shader using the lines below. DO NOT MODIFY THIS FILE! Add the code in your calling function:
// GLint last_program;
// glGetIntegerv(GL_CURRENT_PROGRAM, &last_program);
// glUseProgram(0);
// ImGui_ImplOpenGL2_RenderDrawData(...);
// glUseProgram(last_program)
// you may need to backup/reset/restore other state, e.g. for current shader using the commented lines below.
// (DO NOT MODIFY THIS FILE! Add the code in your calling function)
// GLint last_program;
// glGetIntegerv(GL_CURRENT_PROGRAM, &last_program);
// glUseProgram(0);
// ImGui_ImplOpenGL2_RenderDrawData(...);
// glUseProgram(last_program)
// There are potentially many more states you could need to clear/setup that we can't access from default headers.
// e.g. glBindBuffer(GL_ARRAY_BUFFER, 0), glDisable(GL_TEXTURE_CUBE_MAP).
// Setup viewport, orthographic projection matrix
// 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.
@ -128,6 +135,7 @@ void ImGui_ImplOpenGL2_RenderDrawData(ImDrawData* draw_data)
GLint last_polygon_mode[2]; glGetIntegerv(GL_POLYGON_MODE, last_polygon_mode);
GLint last_viewport[4]; glGetIntegerv(GL_VIEWPORT, last_viewport);
GLint last_scissor_box[4]; glGetIntegerv(GL_SCISSOR_BOX, last_scissor_box);
GLint last_shade_model; glGetIntegerv(GL_SHADE_MODEL, &last_shade_model);
GLint last_tex_env_mode; glGetTexEnviv(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, &last_tex_env_mode);
glPushAttrib(GL_ENABLE_BIT | GL_COLOR_BUFFER_BIT | GL_TRANSFORM_BIT);
@ -196,6 +204,7 @@ void ImGui_ImplOpenGL2_RenderDrawData(ImDrawData* draw_data)
glPolygonMode(GL_FRONT, (GLenum)last_polygon_mode[0]); glPolygonMode(GL_BACK, (GLenum)last_polygon_mode[1]);
glViewport(last_viewport[0], last_viewport[1], (GLsizei)last_viewport[2], (GLsizei)last_viewport[3]);
glScissor(last_scissor_box[0], last_scissor_box[1], (GLsizei)last_scissor_box[2], (GLsizei)last_scissor_box[3]);
glShadeModel(last_shade_model);
glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, last_tex_env_mode);
}