[Bf-blender-cvs] [a394f4e] blender2.8: OpenGL: edge shader discards fragments of unused edges

[Mike Erwin]

Commit: a394f4e545f0ffaf0a65bdb492714a7d8d7a28e5
Author: Mike Erwin
Date:   Wed Oct 26 03:57:14 2016 -0400
Branches: blender2.8
https://developer.blender.org/rBa394f4e545f0ffaf0a65bdb492714a7d8d7a28e5

OpenGL: edge shader discards fragments of unused edges

Discarded edges should not update depth buffer or blend with color buffer.

Geometry shader version will make this obsolete.

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

M	source/blender/gpu/CMakeLists.txt
M	source/blender/gpu/intern/gpu_shader.c
A	source/blender/gpu/shaders/gpu_shader_flat_color_alpha_test_0_frag.glsl

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

diff --git a/source/blender/gpu/CMakeLists.txt b/source/blender/gpu/CMakeLists.txt
index 17bf77f..607d66b 100644
--- a/source/blender/gpu/CMakeLists.txt
+++ b/source/blender/gpu/CMakeLists.txt
@@ -129,6 +129,7 @@ set(SRC
 data_to_c_simple(shaders/gpu_shader_depth_only_frag.glsl SRC)
 data_to_c_simple(shaders/gpu_shader_uniform_color_frag.glsl SRC)
 data_to_c_simple(shaders/gpu_shader_flat_color_frag.glsl SRC)
+data_to_c_simple(shaders/gpu_shader_flat_color_alpha_test_0_frag.glsl SRC)
 data_to_c_simple(shaders/gpu_shader_2D_vert.glsl SRC)
 data_to_c_simple(shaders/gpu_shader_2D_flat_color_vert.glsl SRC)
 data_to_c_simple(shaders/gpu_shader_2D_smooth_color_vert.glsl SRC)
diff --git a/source/blender/gpu/intern/gpu_shader.c b/source/blender/gpu/intern/gpu_shader.c
index 6b6cdfb..2e1c3b7 100644
--- a/source/blender/gpu/intern/gpu_shader.c
+++ b/source/blender/gpu/intern/gpu_shader.c
@@ -49,6 +49,7 @@
 extern char datatoc_gpu_shader_depth_only_frag_glsl[];
 extern char datatoc_gpu_shader_uniform_color_frag_glsl[];
 extern char datatoc_gpu_shader_flat_color_frag_glsl[];
+extern char datatoc_gpu_shader_flat_color_alpha_test_0_frag_glsl[];
 extern char datatoc_gpu_shader_2D_vert_glsl[];
 extern char datatoc_gpu_shader_2D_flat_color_vert_glsl[];
 extern char datatoc_gpu_shader_2D_smooth_color_vert_glsl[];
@@ -664,7 +665,7 @@ GPUShader *GPU_shader_get_builtin_shader(GPUBuiltinShader shader)
 			if (!GG.shaders.edges_front_back_persp)
 				GG.shaders.edges_front_back_persp = GPU_shader_create(
 				        datatoc_gpu_shader_edges_front_back_persp_vert_glsl,
-				        datatoc_gpu_shader_flat_color_frag_glsl,
+				        datatoc_gpu_shader_flat_color_alpha_test_0_frag_glsl,
 				        NULL, NULL, NULL, 0, 0, 0);
 			retval = GG.shaders.edges_front_back_persp;
 			break;
diff --git a/source/blender/gpu/shaders/gpu_shader_flat_color_alpha_test_0_frag.glsl b/source/blender/gpu/shaders/gpu_shader_flat_color_alpha_test_0_frag.glsl
new file mode 100644
index 0000000..10b4c2a
--- /dev/null
+++ b/source/blender/gpu/shaders/gpu_shader_flat_color_alpha_test_0_frag.glsl
@@ -0,0 +1,16 @@
+
+#if __VERSION__ == 120
+  flat varying vec4 finalColor;
+  #define fragColor gl_FragColor
+#else
+  flat in vec4 finalColor;
+  out vec4 fragColor;
+#endif
+
+void main()
+{
+	if (finalColor.a > 0.0)
+		fragColor = finalColor;
+	else
+		discard;
+}