[Bf-blender-cvs] [c28a4eb8cb8] blender2.8: Eevee: fix some glsl for low quality lamps.

[Clément Foucault]

Commit: c28a4eb8cb8c5abc3307c6a27b24ef274c72083c
Author: Clément Foucault
Date:   Mon May 15 16:13:39 2017 +0200
Branches: blender2.8
https://developer.blender.org/rBc28a4eb8cb8c5abc3307c6a27b24ef274c72083c

Eevee: fix some glsl for low quality lamps.

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

M	source/blender/draw/engines/eevee/shaders/bsdf_common_lib.glsl
M	source/blender/draw/engines/eevee/shaders/bsdf_direct_lib.glsl
M	source/blender/draw/engines/eevee/shaders/lit_surface_frag.glsl
M	source/blender/draw/engines/eevee/shaders/ltc_lib.glsl

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

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 ef8af646ec1..1954a2ad85d 100644
--- a/source/blender/draw/engines/eevee/shaders/bsdf_common_lib.glsl
+++ b/source/blender/draw/engines/eevee/shaders/bsdf_common_lib.glsl
@@ -5,6 +5,8 @@
 #define M_1_2PI     0.159154943091895335768  /* 1/(2*pi) */
 #define M_1_PI2     0.101321183642337771443  /* 1/(pi^2) */
 
+#define LUT_SIZE 64
+
 /* ------- Structures -------- */
 
 struct LightData {
@@ -127,6 +129,16 @@ vec3 line_aligned_plane_intersect(vec3 lineorigin, vec3 linedirection, vec3 plan
 	return lineorigin + linedirection * dist;
 }
 
+/* Return texture coordinates to sample Surface LUT */
+vec2 lut_coords(float cosTheta, float roughness)
+{
+	float theta = acos(cosTheta);
+	vec2 coords = vec2(roughness, theta / M_PI_2);
+
+	/* scale and bias coordinates, for correct filtered lookup */
+	return coords * (LUT_SIZE - 1.0) / LUT_SIZE + 0.5 / LUT_SIZE;
+}
+
 /* -- Tangent Space conversion -- */
 vec3 tangent_to_world(vec3 vector, vec3 N, vec3 T, vec3 B)
 {
diff --git a/source/blender/draw/engines/eevee/shaders/bsdf_direct_lib.glsl b/source/blender/draw/engines/eevee/shaders/bsdf_direct_lib.glsl
index b0f31a403c7..a949f85b426 100644
--- a/source/blender/draw/engines/eevee/shaders/bsdf_direct_lib.glsl
+++ b/source/blender/draw/engines/eevee/shaders/bsdf_direct_lib.glsl
@@ -96,13 +96,13 @@ vec3 direct_ggx_point(ShadingData sd, float roughness, vec3 f0)
 vec3 direct_ggx_sphere(LightData ld, ShadingData sd, float roughness, vec3 f0)
 {
 #ifdef USE_LTC
+	float NV = max(dot(sd.N, sd.V), 1e-8);
 	vec3 P = line_aligned_plane_intersect(vec3(0.0), sd.spec_dominant_dir, sd.l_vector);
 
 	vec3 Px = normalize(P - sd.l_vector) * ld.l_radius;
 	vec3 Py = cross(Px, sd.L);
 
-	float NV = max(dot(sd.N, sd.V), 1e-8);
-	vec2 uv = ltc_coords(NV, sqrt(roughness));
+	vec2 uv = lut_coords(NV, sqrt(roughness));
 	mat3 ltcmat = ltc_matrix(uv);
 
 // #define HIGHEST_QUALITY
@@ -148,7 +148,7 @@ vec3 direct_ggx_sphere(LightData ld, ShadingData sd, float roughness, vec3 f0)
 
 	/* Fresnel */
 	float VH = max(dot(sd.V, normalize(sd.V + sd.L)), 0.0);
-	vec3 spec = F_schlick(f0, NV) * bsdf;
+	vec3 spec = F_schlick(f0, VH) * bsdf;
 #endif
 	return spec;
 }
@@ -157,7 +157,7 @@ vec3 direct_ggx_rectangle(LightData ld, ShadingData sd, float roughness, vec3 f0
 {
 #ifdef USE_LTC
 	float NV = max(dot(sd.N, sd.V), 1e-8);
-	vec2 uv = ltc_coords(NV, sqrt(roughness));
+	vec2 uv = lut_coords(NV, sqrt(roughness));
 	mat3 ltcmat = ltc_matrix(uv);
 
 	float bsdf = ltc_evaluate(sd.N, sd.V, ltcmat, sd.area_data.corner);
@@ -180,7 +180,7 @@ vec3 direct_ggx_rectangle(LightData ld, ShadingData sd, float roughness, vec3 f0
 
 	/* Fresnel */
 	float VH = max(dot(sd.V, normalize(sd.V + sd.L)), 0.0);
-	vec3 spec = F_schlick(f0, NV) * bsdf;
+	vec3 spec = F_schlick(f0, VH) * bsdf;
 #endif
 	return spec;
 }
diff --git a/source/blender/draw/engines/eevee/shaders/lit_surface_frag.glsl b/source/blender/draw/engines/eevee/shaders/lit_surface_frag.glsl
index b0a99d8e72b..769d8dcd7bb 100644
--- a/source/blender/draw/engines/eevee/shaders/lit_surface_frag.glsl
+++ b/source/blender/draw/engines/eevee/shaders/lit_surface_frag.glsl
@@ -264,7 +264,7 @@ vec3 eevee_surface_lit(vec3 world_normal, vec3 albedo, vec3 f0, float roughness,
 	}
 
 	/* Envmaps */
-	vec2 uv = ltc_coords(dot(sd.N, sd.V), sqrt(roughness));
+	vec2 uv = lut_coords(dot(sd.N, sd.V), sqrt(roughness));
 	vec2 brdf_lut = texture(brdfLut, uv).rg;
 	vec3 Li = textureLod(probeFiltered, sd.spec_dominant_dir, roughness * lodMax).rgb;
 	indirect_radiance += Li * brdf_lut.y + f0 * Li * brdf_lut.x;
diff --git a/source/blender/draw/engines/eevee/shaders/ltc_lib.glsl b/source/blender/draw/engines/eevee/shaders/ltc_lib.glsl
index 279b18313e7..5ea13cab271 100644
--- a/source/blender/draw/engines/eevee/shaders/ltc_lib.glsl
+++ b/source/blender/draw/engines/eevee/shaders/ltc_lib.glsl
@@ -1,7 +1,6 @@
 /* Mainly From https://eheitzresearch.wordpress.com/415-2/ */
 
 #define USE_LTC
-#define LTC_LUT_SIZE 64
 
 uniform sampler2D ltcMat;
 uniform sampler2D brdfLut;
@@ -146,15 +145,6 @@ int clip_quad_to_horizon(inout vec3 L[5])
 	return n;
 }
 
-vec2 ltc_coords(float cosTheta, float roughness)
-{
-	float theta = acos(cosTheta);
-	vec2 coords = vec2(roughness, theta/(0.5*3.14159));
-
-	/* scale and bias coordinates, for correct filtered lookup */
-	return coords * (LTC_LUT_SIZE - 1.0) / LTC_LUT_SIZE + 0.5 / LTC_LUT_SIZE;
-}
-
 mat3 ltc_matrix(vec2 coord)
 {
 	/* load inverse matrix */