Eevee: SSR: Optimise Texture fetches and solve noise issue.

There was some remaining issue caused by neighbor re-use. Randomizing them every _prime_number_ of iterations fixes this.

1 files changed, 4 insertions, 0 deletions

diff --git a/source/blender/draw/engines/eevee/shaders/bsdf_common_lib.glsl b/source/blender/draw/engines/eevee/shaders/bsdf_common_lib.glsl
index a9350dbc632..ff3e1717ca8 100644
--- a/source/blender/draw/engines/eevee/shaders/bsdf_common_lib.glsl
+++ b/source/blender/draw/engines/eevee/shaders/bsdf_common_lib.glsl
@@ -125,6 +125,10 @@ float min_v3(vec3 v) { return min(v.x, min(v.y, v.z)); }
 float max_v2(vec2 v) { return max(v.x, v.y); }
 float max_v3(vec3 v) { return max(v.x, max(v.y, v.z)); }
 
+float sum(vec2 v) { return dot(vec2(1.0), v); }
+float sum(vec3 v) { return dot(vec3(1.0), v); }
+float sum(vec4 v) { return dot(vec4(1.0), v); }
+
 float saturate(float a) { return clamp(a, 0.0, 1.0); }
 vec2 saturate(vec2 a) { return clamp(a, 0.0, 1.0); }
 vec3 saturate(vec3 a) { return clamp(a, 0.0, 1.0); }