Cycles: Simplify check for degenerated faces on GPU

Still not sure how to properly solve the issue, needs some trickery to get
actual optimized values from intersection function (using printf() avoids
some optimization and makes stuff render correct).

For the time being let's just simplify check.

1 files changed, 1 insertions, 6 deletions

diff --git a/intern/cycles/kernel/geom/geom_triangle_intersect.h b/intern/cycles/kernel/geom/geom_triangle_intersect.h
index d2957ad5474..4e2f46d58d3 100644
--- a/intern/cycles/kernel/geom/geom_triangle_intersect.h
+++ b/intern/cycles/kernel/geom/geom_triangle_intersect.h
@@ -160,15 +160,10 @@ ccl_device_inline bool triangle_intersect(KernelGlobals *kg,
 #endif
 	{
 #ifdef __KERNEL_GPU__
-		float4 a = tri_b - tri_a, b = tri_c - tri_a;
-		if(len_squared(make_float3(a.y*b.z - a.z*b.y,
-		                           a.z*b.x - a.x*b.z,
-		                           a.x*b.y - a.y*b.x)) == 0.0f)
-		{
+		if(A == B && B == C) {
 			return false;
 		}
 #endif
-
 		/* Normalize U, V, W, and T. */
 		const float inv_det = 1.0f / det;
 		isect->prim = triAddr;