* QMC Raytracing

This introduces QMC sampling for use in glossy reflections/refractions, soft raytraced shadows, and ambient occlusion.

This work includes many new features and speed-ups, so check out the nice docs here:

Glossy Reflection/Refraction
http://www.blender.org/development/current-projects/changes-since-244/glossy-reflectionrefraction/

Raytraced Soft Shadows
http://www.blender.org/development/current-projects/changes-since-244/raytraced-soft-shadows/

QMC Sampling
http://www.blender.org/development/current-projects/changes-since-244/qmc-sampling/

Many thanks to Brecht van Lommel for some initial code snippets and for reviewing the patch, and especially to Alfredo de Greef who gave me a lot of guidance and help along the way!

2 files changed, 26 insertions, 0 deletions

diff --git a/source/blender/blenlib/BLI_arithb.h b/source/blender/blenlib/BLI_arithb.h
index b2043bfcf93..fc132250fc6 100644
--- a/source/blender/blenlib/BLI_arithb.h
+++ b/source/blender/blenlib/BLI_arithb.h
@@ -244,6 +244,8 @@ void VecSubf(float *v, float *v1, float *v2);
 void VecLerpf(float *target, float *a, float *b, float t);
 void VecMidf(float *v, float *v1, float *v2);
 
+void VecOrthoBasisf(float *v, float *v1, float *v2);
+
 float Vec2Lenf(float *v1, float *v2);
 void Vec2Mulf(float *v1, float f);
 void Vec2Addf(float *v, float *v1, float *v2);
diff --git a/source/blender/blenlib/intern/arithb.c b/source/blender/blenlib/intern/arithb.c
index d93f4b9c009..f95d102763a 100644
--- a/source/blender/blenlib/intern/arithb.c
+++ b/source/blender/blenlib/intern/arithb.c
@@ -2093,6 +2093,30 @@ void VecMulf(float *v1, float f)
 	v1[2]*= f;
 }
 
+void VecOrthoBasisf(float *v, float *v1, float *v2)
+{
+	if (v[0] == 0.0f && v[1] == 0.0f)
+	{
+		// degenerate case
+		v1[0] = 0.0f; v1[1] = 1.0f; v1[2] = 0.0f;
+		if (v[2] > 0.0f) {
+			v2[0] = 1.0f; v2[1] = v2[2] = 0.0f;
+		}
+		else {
+			v2[0] = -1.0f; v2[1] = v2[2] = 0.0f;
+		}
+	}
+	else 
+	{
+		float f = 1.0f/sqrt(v[0]*v[0] + v[1]*v[1]);
+		v1[0] = v[1]*f;
+		v1[1] = -v[0]*f;
+		v1[2] = 0.0f;
+
+		Crossf(v2, v, v1);
+	}
+}
+
 int VecLenCompare(float *v1, float *v2, float limit)
 {
     float x,y,z;