Browse Source

OpenGL example: made the render function save/restore OpenGL state properly-ish

pull/83/head
ocornut 10 years ago
parent
commit
36e52167da
  1. 11
      examples/opengl_example/main.cpp

11
examples/opengl_example/main.cpp

@ -34,6 +34,7 @@ static void ImImpl_RenderDrawLists(ImDrawList** const cmd_lists, int cmd_lists_c
// We are using the OpenGL fixed pipeline to make the example code simpler to read! // 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. // 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. // 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); glEnable(GL_BLEND);
glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA); glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
glDisable(GL_CULL_FACE); glDisable(GL_CULL_FACE);
@ -51,9 +52,11 @@ static void ImImpl_RenderDrawLists(ImDrawList** const cmd_lists, int cmd_lists_c
const float width = ImGui::GetIO().DisplaySize.x; const float width = ImGui::GetIO().DisplaySize.x;
const float height = ImGui::GetIO().DisplaySize.y; const float height = ImGui::GetIO().DisplaySize.y;
glMatrixMode(GL_PROJECTION); glMatrixMode(GL_PROJECTION);
glPushMatrix();
glLoadIdentity(); glLoadIdentity();
glOrtho(0.0f, width, height, 0.0f, -1.0f, +1.0f); glOrtho(0.0f, width, height, 0.0f, -1.0f, +1.0f);
glMatrixMode(GL_MODELVIEW); glMatrixMode(GL_MODELVIEW);
glPushMatrix();
glLoadIdentity(); glLoadIdentity();
// Render command lists // Render command lists
@ -74,10 +77,16 @@ static void ImImpl_RenderDrawLists(ImDrawList** const cmd_lists, int cmd_lists_c
vtx_offset += pcmd->vtx_count; vtx_offset += pcmd->vtx_count;
} }
} }
glDisable(GL_SCISSOR_TEST);
glDisableClientState(GL_COLOR_ARRAY); glDisableClientState(GL_COLOR_ARRAY);
glDisableClientState(GL_TEXTURE_COORD_ARRAY); glDisableClientState(GL_TEXTURE_COORD_ARRAY);
glDisableClientState(GL_VERTEX_ARRAY); glDisableClientState(GL_VERTEX_ARRAY);
// Restore modified state
glMatrixMode(GL_MODELVIEW);
glPopMatrix();
glMatrixMode(GL_PROJECTION);
glPopMatrix();
glPopAttrib();
} }
// NB: ImGui already provide OS clipboard support for Windows so this isn't needed if you are using Windows only. // NB: ImGui already provide OS clipboard support for Windows so this isn't needed if you are using Windows only.

Loading…
Cancel
Save