Fix T43689, viewport compositing does not respect alpha settings for

background.

For SSAO supporting this is no problem, for DOF we would ideally do
blurred alpha, but alpha channel in blurred buffers is occupied by coc
field, so use original color alpha instead. It's not entirely correct
but it's better than nothing.

2 files changed, 6 insertions, 3 deletions

diff --git a/source/blender/gpu/shaders/gpu_shader_fx_dof_frag.glsl b/source/blender/gpu/shaders/gpu_shader_fx_dof_frag.glsl
index d52ab2243fe..e9dab04de5d 100644
--- a/source/blender/gpu/shaders/gpu_shader_fx_dof_frag.glsl
+++ b/source/blender/gpu/shaders/gpu_shader_fx_dof_frag.glsl
@@ -186,7 +186,9 @@ void fifth_pass()
 	vec4 color = factors.x * color_orig + factors.y * smallblurred + factors.z * mediumblurred + factors.w * highblurred;
 
 	color /= dot(factors, vec4(1.0));
-	gl_FragColor = vec4(color.rgb, 1.0);
+	/* using original color is not correct, but use that for now because alpha of
+	 * blurred buffers uses CoC instead */
+	gl_FragColor = vec4(color.rgb, color_orig.a);
 }
 
 
diff --git a/source/blender/gpu/shaders/gpu_shader_fx_ssao_frag.glsl b/source/blender/gpu/shaders/gpu_shader_fx_ssao_frag.glsl
index b33fda92a46..86e10af8c0d 100644
--- a/source/blender/gpu/shaders/gpu_shader_fx_ssao_frag.glsl
+++ b/source/blender/gpu/shaders/gpu_shader_fx_ssao_frag.glsl
@@ -77,6 +77,7 @@ float calculate_ssao_factor(float depth)
 void main()
 {
 	float depth = texture2D(depthbuffer, uvcoordsvar.xy).r;
-	vec4 color = mix(texture2D(colorbuffer, uvcoordsvar.xy), ssao_color, calculate_ssao_factor(depth));
-	gl_FragColor = vec4(color.rgb, 1.0);
+	vec4 scene_col = texture2D(colorbuffer, uvcoordsvar.xy);
+	vec3 final_color = mix(scene_col.rgb, ssao_color.rgb, calculate_ssao_factor(depth));
+	gl_FragColor = vec4(final_color.rgb, scene_col.a);
 }