[Bf-blender-cvs] [37693283055] temp-T94900-b: Fix T94900: Fix drawing artifacts sequencer+node editor.

[Jeroen Bakker]

Commit: 37693283055ce189616d9e7d0b4d4beaa7856ad6
Author: Jeroen Bakker
Date:   Wed Jan 26 14:40:56 2022 +0100
Branches: temp-T94900-b
https://developer.blender.org/rB37693283055ce189616d9e7d0b4d4beaa7856ad6

Fix T94900: Fix drawing artifacts sequencer+node editor.

The VSE and node editor only uses an overlay buffer to draw to the screen. The
GPUViewport assumes that platforms clears all textures during creation, but
they do not on selected platforms. What would lead to drawing from
uncleared memory.

This patch fixes this by clearing all viewport textures during creation.

===================================================================

M	source/blender/gpu/intern/gpu_viewport.c

===================================================================

diff --git a/source/blender/gpu/intern/gpu_viewport.c b/source/blender/gpu/intern/gpu_viewport.c
index c604859fa94..50f7dc2312a 100644
--- a/source/blender/gpu/intern/gpu_viewport.c
+++ b/source/blender/gpu/intern/gpu_viewport.c
@@ -137,19 +137,25 @@ struct DRWData **GPU_viewport_data_get(GPUViewport *viewport)
 static void gpu_viewport_textures_create(GPUViewport *viewport)
 {
   int *size = viewport->size;
+  static float empty_pixel_fl[4] = {0.0f, 0.0f, 0.0f, 0.0f};
+  static uchar empty_pixel_u[4] = {0, 0, 0, 0};
 
   if (viewport->color_render_tx[0] == NULL) {
     viewport->color_render_tx[0] = GPU_texture_create_2d(
         "dtxl_color", UNPACK2(size), 1, GPU_RGBA16F, NULL);
+    GPU_texture_clear(viewport->color_render_tx[0], GPU_DATA_FLOAT, empty_pixel_fl);
     viewport->color_overlay_tx[0] = GPU_texture_create_2d(
         "dtxl_color_overlay", UNPACK2(size), 1, GPU_SRGB8_A8, NULL);
+    GPU_texture_clear(viewport->color_overlay_tx[0], GPU_DATA_UBYTE, empty_pixel_u);
   }
 
   if ((viewport->flag & GPU_VIEWPORT_STEREO) != 0 && viewport->color_render_tx[1] == NULL) {
     viewport->color_render_tx[1] = GPU_texture_create_2d(
         "dtxl_color_stereo", UNPACK2(size), 1, GPU_RGBA16F, NULL);
+    GPU_texture_clear(viewport->color_render_tx[1], GPU_DATA_FLOAT, empty_pixel_fl);
     viewport->color_overlay_tx[1] = GPU_texture_create_2d(
         "dtxl_color_overlay_stereo", UNPACK2(size), 1, GPU_SRGB8_A8, NULL);
+    GPU_texture_clear(viewport->color_overlay_tx[1], GPU_DATA_UBYTE, empty_pixel_u);
   }
 
   /* Can be shared with GPUOffscreen. */