Cycles: fixes to make CUDA 4.2 work, compiling gave errors in shadows and

other places, was mainly due to instancing not working, but also found
issues in procedural textures.

The problem was with --use_fast_math, this seems to now have way lower
precision for some operations. Disabled this flag and selectively use
fast math functions. Did not find performance regression on GTX 460 after
doing this.

1 files changed, 8 insertions, 4 deletions

diff --git a/intern/cycles/util/util_transform.h b/intern/cycles/util/util_transform.h
index e4897ee6787..b460c4c87a2 100644
--- a/intern/cycles/util/util_transform.h
+++ b/intern/cycles/util/util_transform.h
@@ -61,16 +61,20 @@ __device_inline float3 transform_perspective(const Transform *t, const float3 a)
 
 __device_inline float3 transform_point(const Transform *t, const float3 a)
 {
-	float4 b = make_float4(a.x, a.y, a.z, 1.0f);
-	float3 c = make_float3(dot(t->x, b), dot(t->y, b), dot(t->z, b));
+	float3 c = make_float3(
+		a.x*t->x.x + a.y*t->x.y + a.z*t->x.z + t->x.w,
+		a.x*t->y.x + a.y*t->y.y + a.z*t->y.z + t->y.w,
+		a.x*t->z.x + a.y*t->z.y + a.z*t->z.z + t->z.w);
 
 	return c;
 }
 
 __device_inline float3 transform_direction(const Transform *t, const float3 a)
 {
-	float4 b = make_float4(a.x, a.y, a.z, 0.0f);
-	float3 c = make_float3(dot(t->x, b), dot(t->y, b), dot(t->z, b));
+	float3 c = make_float3(
+		a.x*t->x.x + a.y*t->x.y + a.z*t->x.z,
+		a.x*t->y.x + a.y*t->y.y + a.z*t->y.z,
+		a.x*t->z.x + a.y*t->z.y + a.z*t->z.z);
 
 	return c;
 }