1 files changed, 59 insertions, 0 deletions
diff --git a/intern/cycles/render/constant_fold.h b/intern/cycles/render/constant_fold.h
new file mode 100644
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+++ b/intern/cycles/render/constant_fold.h
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+/*
+ * Copyright 2011-2013 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 __CONSTANT_FOLD_H__
+#define __CONSTANT_FOLD_H__
+
+#include "util_types.h"
+
+CCL_NAMESPACE_BEGIN
+
+class ShaderGraph;
+class ShaderInput;
+class ShaderNode;
+class ShaderOutput;
+
+class ConstantFolder {
+public:
+	ShaderGraph *const graph;
+	ShaderNode *const node;
+	ShaderOutput *const output;
+
+	ConstantFolder(ShaderGraph *graph, ShaderNode *node, ShaderOutput *output);
+
+	bool all_inputs_constant() const;
+
+	/* Constant folding helpers, always return true for convenience. */
+	void make_constant(float value) const;
+	void make_constant(float3 value) const;
+	void make_constant_clamp(float value, bool clamp) const;
+	void make_constant_clamp(float3 value, bool clamp) const;
+
+	/* Bypass node, relinking to another output socket. */
+	void bypass(ShaderOutput *output) const;
+
+	/* For closure nodes, discard node entirely or bypass to one of its inputs. */
+	void discard() const;
+	void bypass_or_discard(ShaderInput *input) const;
+
+	/* Bypass or make constant, unless we can't due to clamp being true. */
+	bool try_bypass_or_make_constant(ShaderInput *input, float3 input_value, bool clamp) const;
+};
+
+CCL_NAMESPACE_END
+
+#endif /* __CONSTANT_FOLD_H__ */
+