Cleanup: GPU: Move towards an explicit Blend state

This make use of the GLStateStack functions for:
- `GPU_blend()`
- `GPU_blend_set_func()`
- `GPU_blend_set_func_separate()`

The goal is to unify them using an explicit state setting.
This will remove the need to use obscure blend functions

3 files changed, 1 insertions, 5 deletions

diff --git a/source/blender/windowmanager/intern/wm_draw.c b/source/blender/windowmanager/intern/wm_draw.c
index bfc155dce16..a9af4f16747 100644
--- a/source/blender/windowmanager/intern/wm_draw.c
+++ b/source/blender/windowmanager/intern/wm_draw.c
@@ -577,8 +577,8 @@ void wm_draw_region_blend(ARegion *region, int view, bool blend)
 
   if (blend) {
     /* GL_ONE because regions drawn offscreen have premultiplied alpha. */
-    GPU_blend_set_func(GPU_ONE, GPU_ONE_MINUS_SRC_ALPHA);
     GPU_blend(true);
+    GPU_blend_set_func(GPU_ONE, GPU_ONE_MINUS_SRC_ALPHA);
   }
 
   /* setup actual texture */
@@ -603,7 +603,6 @@ void wm_draw_region_blend(ARegion *region, int view, bool blend)
   GPU_texture_unbind(texture);
 
   if (blend) {
-    GPU_blend_set_func(GPU_SRC_ALPHA, GPU_ONE_MINUS_SRC_ALPHA);
     GPU_blend(false);
   }
 }
diff --git a/source/blender/windowmanager/intern/wm_gesture.c b/source/blender/windowmanager/intern/wm_gesture.c
index 55233168ab2..abe8364d7c3 100644
--- a/source/blender/windowmanager/intern/wm_gesture.c
+++ b/source/blender/windowmanager/intern/wm_gesture.c
@@ -370,7 +370,6 @@ static void draw_filled_lasso(wmGesture *gt)
     MEM_freeN(pixel_buf);
 
     GPU_blend(false);
-    GPU_blend_set_func(GPU_SRC_ALPHA, GPU_ONE_MINUS_SRC_ALPHA);
   }
 
   MEM_freeN(mcoords);
diff --git a/source/blender/windowmanager/intern/wm_init_exit.c b/source/blender/windowmanager/intern/wm_init_exit.c
index 075469743ec..e8f663b0c4a 100644
--- a/source/blender/windowmanager/intern/wm_init_exit.c
+++ b/source/blender/windowmanager/intern/wm_init_exit.c
@@ -350,8 +350,6 @@ void WM_init(bContext *C, int argc, const char **argv)
   BKE_material_copybuf_clear();
   ED_render_clear_mtex_copybuf();
 
-  // GPU_blend_set_func(GPU_SRC_ALPHA, GPU_ONE_MINUS_SRC_ALPHA, GPU_ONE, GPU_ONE_MINUS_SRC_ALPHA);
-
   wm_history_file_read();
 
   /* allow a path of "", this is what happens when making a new file */