[Bf-blender-cvs] [1fe561e6623] blender2.8: Eevee: Wireframe: Increase precision a bit

[Clément Foucault]

Commit: 1fe561e6623697d6d2f3f0e22dd609109ee65261
Author: Clément Foucault
Date:   Tue Nov 6 20:52:06 2018 +0100
Branches: blender2.8
https://developer.blender.org/rB1fe561e6623697d6d2f3f0e22dd609109ee65261

Eevee: Wireframe: Increase precision a bit

Take the full derivative and compute its length instead of using fwidth.

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M	source/blender/gpu/shaders/gpu_shader_material.glsl

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diff --git a/source/blender/gpu/shaders/gpu_shader_material.glsl b/source/blender/gpu/shaders/gpu_shader_material.glsl
index 4039b20a082..e5740babebc 100644
--- a/source/blender/gpu/shaders/gpu_shader_material.glsl
+++ b/source/blender/gpu/shaders/gpu_shader_material.glsl
@@ -1445,7 +1445,10 @@ void node_wireframe_screenspace(float size, vec2 barycentric, out float fac)
 	barys.z = 1.0 - barycentric.x - barycentric.y;
 
 	size *= (1.0 / 3.0);
-	vec3 deltas = fwidth(barys);
+	vec3 dx = dFdx(barys);
+	vec3 dy = dFdy(barys);
+	vec3 deltas = sqrt(dx * dx + dy * dy);
+
 	vec3 s = step(-deltas * size, -barys);
 
 	fac = max(s.x, max(s.y, s.z));