Backends: Rework blending equation to preserve alpha in output buffer accross all backends. (#2693, #2764, #2766, #2873, #3447, #3813, #3816)

Some of the viewport ideas from #2766 are not in there yet (e.g. Vulkan: setting compositeAlpha based on cap.supportedCompositeAlpha)
This commit is contained in:
ocornut
2021-02-17 19:29:07 +01:00
parent 27a5bdb916
commit bda12e5fdd
11 changed files with 31 additions and 14 deletions

View File

@ -81,6 +81,7 @@ static void ImGui_ImplOpenGL2_SetupRenderState(ImDrawData* draw_data, int fb_wid
// Setup render state: alpha-blending enabled, no face culling, no depth testing, scissor enabled, vertex/texcoord/color pointers, polygon fill.
glEnable(GL_BLEND);
glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
//glBlendFuncSeparate(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA, GL_ONE, GL_ONE_MINUS_SRC_ALPHA); // In order to composite our output buffer we need to preserve alpha
glDisable(GL_CULL_FACE);
glDisable(GL_DEPTH_TEST);
glDisable(GL_STENCIL_TEST);