1 files changed, 110 insertions, 0 deletions
diff --git a/intern/cycles/bvh/bvh_split.h b/intern/cycles/bvh/bvh_split.h
new file mode 100644
index 00000000000..1f4befbe8e2
--- /dev/null
+++ b/intern/cycles/bvh/bvh_split.h
@@ -0,0 +1,110 @@
+/*
+ * Adapted from code copyright 2009-2010 NVIDIA Corporation
+ * Modifications Copyright 2011, Blender Foundation.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef __BVH_SPLIT_H__
+#define __BVH_SPLIT_H__
+
+#include "bvh_build.h"
+#include "bvh_params.h"
+
+CCL_NAMESPACE_BEGIN
+
+class BVHBuild;
+
+/* Object Split */
+
+class BVHObjectSplit
+{
+public:
+	float sah;
+	int dim;
+	int num_left;
+	BoundBox left_bounds;
+	BoundBox right_bounds;
+
+	BVHObjectSplit() {}
+	BVHObjectSplit(BVHBuild *builder, const BVHRange& range, float nodeSAH);
+
+	void split(BVHBuild *builder, BVHRange& left, BVHRange& right, const BVHRange& range);
+};
+
+/* Spatial Split */
+
+class BVHSpatialSplit
+{
+public:
+	float sah;
+	int dim;
+	float pos;
+
+	BVHSpatialSplit() : sah(FLT_MAX), dim(0), pos(0.0f) {}
+	BVHSpatialSplit(BVHBuild *builder, const BVHRange& range, float nodeSAH);
+
+	void split(BVHBuild *builder, BVHRange& left, BVHRange& right, const BVHRange& range);
+	void split_reference(BVHBuild *builder, BVHReference& left, BVHReference& right, const BVHReference& ref, int dim, float pos);
+};
+
+/* Mixed Object-Spatial Split */
+
+class BVHMixedSplit
+{
+public:
+	BVHObjectSplit object;
+	BVHSpatialSplit spatial;
+
+	float leafSAH;
+	float nodeSAH;
+	float minSAH;
+
+	bool no_split;
+
+	__forceinline BVHMixedSplit(BVHBuild *builder, const BVHRange& range, int level)
+	{
+		/* find split candidates. */
+		float area = range.bounds().safe_area();
+
+		leafSAH = area * builder->params.triangle_cost(range.size());
+		nodeSAH = area * builder->params.node_cost(2);
+
+		object = BVHObjectSplit(builder, range, nodeSAH);
+
+		if(builder->params.use_spatial_split && level < BVHParams::MAX_SPATIAL_DEPTH) {
+			BoundBox overlap = object.left_bounds;
+			overlap.intersect(object.right_bounds);
+
+			if(overlap.safe_area() >= builder->spatial_min_overlap)
+				spatial = BVHSpatialSplit(builder, range, nodeSAH);
+		}
+
+		/* leaf SAH is the lowest => create leaf. */
+		minSAH = min(min(leafSAH, object.sah), spatial.sah);
+		no_split = (minSAH == leafSAH && range.size() <= builder->params.max_leaf_size);
+	}
+
+	__forceinline void split(BVHBuild *builder, BVHRange& left, BVHRange& right, const BVHRange& range)
+	{
+		if(builder->params.use_spatial_split && minSAH == spatial.sah)
+			spatial.split(builder, left, right, range);
+		if(!left.size() || !right.size())
+			object.split(builder, left, right, range);
+	}
+};
+
+CCL_NAMESPACE_END
+
+#endif /* __BVH_SPLIT_H__ */
+