1 files changed, 30 insertions, 12 deletions

diff --git a/intern/cycles/util/util_math.h b/intern/cycles/util/util_math.h
index 32924f9a8c2..cfe6fa65143 100644
--- a/intern/cycles/util/util_math.h
+++ b/intern/cycles/util/util_math.h
@@ -545,6 +545,11 @@ ccl_device_inline float3 normalize(const float3 a)
 
 #endif
 
+ccl_device_inline float3 saturate3(float3 a)
+{
+	return make_float3(saturate(a.x), saturate(a.y), saturate(a.z));
+}
+
 ccl_device_inline float3 normalize_len(const float3 a, float *t)
 {
 	*t = len(a);
@@ -1329,6 +1334,15 @@ ccl_device float safe_modulo(float a, float b)
 	return (b != 0.0f)? fmodf(a, b): 0.0f;
 }
 
+ccl_device_inline float beta(float x, float y)
+{
+#ifndef __KERNEL_OPENCL__
+	return expf(lgammaf(x) + lgammaf(y) - lgammaf(x+y));
+#else
+	return expf(lgamma(x) + lgamma(y) - lgamma(x+y));
+#endif
+}
+
 /* Ray Intersection */
 
 ccl_device bool ray_sphere_intersect(
@@ -1479,21 +1493,25 @@ ccl_device bool ray_triangle_intersect_uv(
 	return true;
 }
 
-ccl_device bool ray_quad_intersect(float3 ray_P, float3 ray_D, float ray_t,
-                                   float3 quad_P, float3 quad_u, float3 quad_v,
+ccl_device bool ray_quad_intersect(float3 ray_P, float3 ray_D, float ray_mint, float ray_maxt,
+                                   float3 quad_P, float3 quad_u, float3 quad_v, float3 quad_n,
                                    float3 *isect_P, float *isect_t)
 {
-	float3 v0 = quad_P - quad_u*0.5f - quad_v*0.5f;
-	float3 v1 = quad_P + quad_u*0.5f - quad_v*0.5f;
-	float3 v2 = quad_P + quad_u*0.5f + quad_v*0.5f;
-	float3 v3 = quad_P - quad_u*0.5f + quad_v*0.5f;
+	float t = -(dot(ray_P, quad_n) - dot(quad_P, quad_n)) / dot(ray_D, quad_n);
+	if(t < ray_mint || t > ray_maxt)
+		return false;
 
-	if(ray_triangle_intersect(ray_P, ray_D, ray_t, v0, v1, v2, isect_P, isect_t))
-		return true;
-	else if(ray_triangle_intersect(ray_P, ray_D, ray_t, v0, v2, v3, isect_P, isect_t))
-		return true;
-	
-	return false;
+	float3 hit = ray_P + t*ray_D;
+	float3 inplane = hit - quad_P;
+	if(fabsf(dot(inplane, quad_u) / dot(quad_u, quad_u)) > 0.5f)
+		return false;
+	if(fabsf(dot(inplane, quad_v) / dot(quad_v, quad_v)) > 0.5f)
+		return false;
+
+	if(isect_P) *isect_P = hit;
+	if(isect_t) *isect_t = t;
+
+	return true;
 }
 
 /* projections */