[Bf-blender-cvs] [47b1279] master: Cycles: Watertight fix for SSS intersection

[Sergey Sharybin]

Commit: 47b1279762dd07cdef4570e077459497f48e4fb8
Author: Sergey Sharybin
Date:   Thu Oct 22 22:10:40 2015 +0500
Branches: master
https://developer.blender.org/rB47b1279762dd07cdef4570e077459497f48e4fb8

Cycles: Watertight fix for SSS intersection

Same as previous commit, just was missing in there.

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

M	intern/cycles/kernel/geom/geom_triangle_intersect.h

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

diff --git a/intern/cycles/kernel/geom/geom_triangle_intersect.h b/intern/cycles/kernel/geom/geom_triangle_intersect.h
index 1ce4eea..970616e 100644
--- a/intern/cycles/kernel/geom/geom_triangle_intersect.h
+++ b/intern/cycles/kernel/geom/geom_triangle_intersect.h
@@ -142,8 +142,8 @@ ccl_device_inline bool triangle_intersect(KernelGlobals *kg,
 	float U = Cx * By - Cy * Bx;
 	float V = Ax * Cy - Ay * Cx;
 	float W = Bx * Ay - By * Ax;
-	if ((U < 0.0f || V < 0.0f || W < 0.0f) &&
-	    (U > 0.0f || V > 0.0f || W > 0.0f))
+	if((U < 0.0f || V < 0.0f || W < 0.0f) &&
+	   (U > 0.0f || V > 0.0f || W > 0.0f))
 	{
 		return false;
 	}
@@ -242,13 +242,12 @@ ccl_device_inline void triangle_intersect_subsurface(
 
 	/* Calculate scaled barycentric coordinates. */
 	float U = Cx * By - Cy * Bx;
-	int sign_mask = (__float_as_int(U) & 0x80000000);
 	float V = Ax * Cy - Ay * Cx;
-	if(sign_mask != (__float_as_int(V) & 0x80000000)) {
-		return;
-	}
 	float W = Bx * Ay - By * Ax;
-	if(sign_mask != (__float_as_int(W) & 0x80000000)) {
+
+	if((U < 0.0f || V < 0.0f || W < 0.0f) &&
+	   (U > 0.0f || V > 0.0f || W > 0.0f))
+	{
 		return;
 	}
 
@@ -261,10 +260,11 @@ ccl_device_inline void triangle_intersect_subsurface(
 	/* Calculate scaled z−coordinates of vertices and use them to calculate
 	 * the hit distance.
 	 */
+	const int sign_det = (__float_as_int(det) & 0x80000000);
 	const float T = (U * A_kz + V * B_kz + W * C_kz) * Sz;
-	const float sign_T = xor_signmask(T, sign_mask);
+	const float sign_T = xor_signmask(T, sign_det);
 	if((sign_T < 0.0f) ||
-	   (sign_T > tmax * xor_signmask(det, sign_mask)))
+	   (sign_T > tmax * xor_signmask(det, sign_det)))
 	{
 		return;
 	}