Fix T47639: OpenGL render with smoke and fire incorrect when using

transparency.

The issue is that we are rendering to a 0..1 clamped sRGB buffer with
unpremultiplied alpha, where the correct thing to do would be to render
to an unclamped linear premultiplied alpha buffer. Then we would just
make fire purely emissive without affecting the alpha channel at all,
but that doesn't work here.

So for now, draw fire and smoke separately using different shaders and
blend modes, like it used to before the smoke programs were rewritten
(see rB0372b642).

1 files changed, 2 insertions, 0 deletions

diff --git a/source/blender/gpu/CMakeLists.txt b/source/blender/gpu/CMakeLists.txt
index cfa083116f2..8885209ce01 100644
--- a/source/blender/gpu/CMakeLists.txt
+++ b/source/blender/gpu/CMakeLists.txt
@@ -78,6 +78,7 @@ set(SRC
 	shaders/gpu_shader_vsm_store_frag.glsl
 	shaders/gpu_shader_vsm_store_vert.glsl
 	shaders/gpu_shader_fx_depth_resolve.glsl
+	shaders/gpu_shader_fire_frag.glsl
 	shaders/gpu_shader_smoke_frag.glsl
 	shaders/gpu_shader_smoke_vert.glsl
 
@@ -99,6 +100,7 @@ set(SRC
 )
 
 data_to_c_simple(shaders/gpu_shader_geometry.glsl SRC)
+data_to_c_simple(shaders/gpu_shader_fire_frag.glsl SRC)
 data_to_c_simple(shaders/gpu_shader_smoke_frag.glsl SRC)
 data_to_c_simple(shaders/gpu_shader_smoke_vert.glsl SRC)
 data_to_c_simple(shaders/gpu_shader_material.glsl SRC)