GPU: remove 'GPU_SHADER_2D_FLAT_COLOR'

The only real difference between `GPU_SHADER_2D_FLAT_COLOR` and
`GPU_SHADER_3D_FLAT_COLOR` is that in the vertex shader the 2D
version uses `vec4(pos, 0.0, 1.0)` and the 3D version uses
`vec4(pos, 1.0)`.

But VBOs with 2D attributes work perfectly in shaders that use 3D
attributes. Components not specified are filled with components from
`vec4(0.0, 0.0, 0.0, 1.0)`.

So there is no real benefit to having two different shader versions.

This will simplify porting shaders to python as it will not be
necessary to use a 3D and a 2D version of the shaders.

In python the new name for '2D_FLAT_COLOR'' and '3D_FLAT_COLOR'
is 'FLAT_COLOR', but the old names still work for backward
compatibility.

1 files changed, 0 insertions, 1 deletions

diff --git a/source/blender/gpu/intern/gpu_immediate.cc b/source/blender/gpu/intern/gpu_immediate.cc
index be1972beab6..8574e886cd0 100644
--- a/source/blender/gpu/intern/gpu_immediate.cc
+++ b/source/blender/gpu/intern/gpu_immediate.cc
@@ -134,7 +134,6 @@ static void wide_line_workaround_start(GPUPrimType prim_type)
     case GPU_SHADER_3D_UNIFORM_COLOR:
       polyline_sh = GPU_SHADER_3D_POLYLINE_UNIFORM_COLOR;
       break;
-    case GPU_SHADER_2D_FLAT_COLOR:
     case GPU_SHADER_3D_FLAT_COLOR:
       polyline_sh = GPU_SHADER_3D_POLYLINE_FLAT_COLOR;
       break;