Cycles: Optimize math node without links to a single value node

Pretty straightforward implementation. Just needed to move some functions
around to make them available at shader compile time.

5 files changed, 89 insertions, 51 deletions

diff --git a/intern/cycles/kernel/CMakeLists.txt b/intern/cycles/kernel/CMakeLists.txt
index c521e1383a4..0ff227938ae 100644
--- a/intern/cycles/kernel/CMakeLists.txt
+++ b/intern/cycles/kernel/CMakeLists.txt
@@ -91,6 +91,7 @@ set(SRC_SVM_HEADERS
 	svm/svm_magic.h
 	svm/svm_mapping.h
 	svm/svm_math.h
+	svm/svm_math_util.h
 	svm/svm_mix.h
 	svm/svm_musgrave.h
 	svm/svm_noise.h
diff --git a/intern/cycles/kernel/svm/svm.h b/intern/cycles/kernel/svm/svm.h
index c13eae813d6..5acfbbf972b 100644
--- a/intern/cycles/kernel/svm/svm.h
+++ b/intern/cycles/kernel/svm/svm.h
@@ -164,6 +164,7 @@ CCL_NAMESPACE_END
 #include "svm_mapping.h"
 #include "svm_normal.h"
 #include "svm_wave.h"
+#include "svm_math_util.h"
 #include "svm_math.h"
 #include "svm_mix.h"
 #include "svm_ramp.h"
diff --git a/intern/cycles/kernel/svm/svm_math.h b/intern/cycles/kernel/svm/svm_math.h
index 1ce9386e40e..e3d8c1f3242 100644
--- a/intern/cycles/kernel/svm/svm_math.h
+++ b/intern/cycles/kernel/svm/svm_math.h
@@ -16,56 +16,6 @@
 
 CCL_NAMESPACE_BEGIN
 
-ccl_device float svm_math(NodeMath type, float Fac1, float Fac2)
-{
-	float Fac;
-
-	if(type == NODE_MATH_ADD)
-		Fac = Fac1 + Fac2;
-	else if(type == NODE_MATH_SUBTRACT)
-		Fac = Fac1 - Fac2;
-	else if(type == NODE_MATH_MULTIPLY)
-		Fac = Fac1*Fac2;
-	else if(type == NODE_MATH_DIVIDE)
-		Fac = safe_divide(Fac1, Fac2);
-	else if(type == NODE_MATH_SINE)
-		Fac = sinf(Fac1);
-	else if(type == NODE_MATH_COSINE)
-		Fac = cosf(Fac1);
-	else if(type == NODE_MATH_TANGENT)
-		Fac = tanf(Fac1);
-	else if(type == NODE_MATH_ARCSINE)
-		Fac = safe_asinf(Fac1);
-	else if(type == NODE_MATH_ARCCOSINE)
-		Fac = safe_acosf(Fac1);
-	else if(type == NODE_MATH_ARCTANGENT)
-		Fac = atanf(Fac1);
-	else if(type == NODE_MATH_POWER)
-		Fac = safe_powf(Fac1, Fac2);
-	else if(type == NODE_MATH_LOGARITHM)
-		Fac = safe_logf(Fac1, Fac2);
-	else if(type == NODE_MATH_MINIMUM)
-		Fac = fminf(Fac1, Fac2);
-	else if(type == NODE_MATH_MAXIMUM)
-		Fac = fmaxf(Fac1, Fac2);
-	else if(type == NODE_MATH_ROUND)
-		Fac = floorf(Fac1 + 0.5f);
-	else if(type == NODE_MATH_LESS_THAN)
-		Fac = Fac1 < Fac2;
-	else if(type == NODE_MATH_GREATER_THAN)
-		Fac = Fac1 > Fac2;
-	else if(type == NODE_MATH_MODULO)
-		Fac = safe_modulo(Fac1, Fac2);
-    else if(type == NODE_MATH_ABSOLUTE)
-        Fac = fabsf(Fac1);
-	else if(type == NODE_MATH_CLAMP)
-		Fac = clamp(Fac1, 0.0f, 1.0f);
-	else
-		Fac = 0.0f;
-	
-	return Fac;
-}
-
 ccl_device float average_fac(float3 v)
 {
 	return (fabsf(v.x) + fabsf(v.y) + fabsf(v.z))/3.0f;
diff --git a/intern/cycles/kernel/svm/svm_math_util.h b/intern/cycles/kernel/svm/svm_math_util.h
new file mode 100644
index 00000000000..b813bf531dc
--- /dev/null
+++ b/intern/cycles/kernel/svm/svm_math_util.h
@@ -0,0 +1,70 @@
+/*
+ * Copyright 2011-2014 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
+ */
+
+CCL_NAMESPACE_BEGIN
+
+ccl_device float svm_math(NodeMath type, float Fac1, float Fac2)
+{
+	float Fac;
+
+	if(type == NODE_MATH_ADD)
+		Fac = Fac1 + Fac2;
+	else if(type == NODE_MATH_SUBTRACT)
+		Fac = Fac1 - Fac2;
+	else if(type == NODE_MATH_MULTIPLY)
+		Fac = Fac1*Fac2;
+	else if(type == NODE_MATH_DIVIDE)
+		Fac = safe_divide(Fac1, Fac2);
+	else if(type == NODE_MATH_SINE)
+		Fac = sinf(Fac1);
+	else if(type == NODE_MATH_COSINE)
+		Fac = cosf(Fac1);
+	else if(type == NODE_MATH_TANGENT)
+		Fac = tanf(Fac1);
+	else if(type == NODE_MATH_ARCSINE)
+		Fac = safe_asinf(Fac1);
+	else if(type == NODE_MATH_ARCCOSINE)
+		Fac = safe_acosf(Fac1);
+	else if(type == NODE_MATH_ARCTANGENT)
+		Fac = atanf(Fac1);
+	else if(type == NODE_MATH_POWER)
+		Fac = safe_powf(Fac1, Fac2);
+	else if(type == NODE_MATH_LOGARITHM)
+		Fac = safe_logf(Fac1, Fac2);
+	else if(type == NODE_MATH_MINIMUM)
+		Fac = fminf(Fac1, Fac2);
+	else if(type == NODE_MATH_MAXIMUM)
+		Fac = fmaxf(Fac1, Fac2);
+	else if(type == NODE_MATH_ROUND)
+		Fac = floorf(Fac1 + 0.5f);
+	else if(type == NODE_MATH_LESS_THAN)
+		Fac = Fac1 < Fac2;
+	else if(type == NODE_MATH_GREATER_THAN)
+		Fac = Fac1 > Fac2;
+	else if(type == NODE_MATH_MODULO)
+		Fac = safe_modulo(Fac1, Fac2);
+	else if(type == NODE_MATH_ABSOLUTE)
+		Fac = fabsf(Fac1);
+	else if(type == NODE_MATH_CLAMP)
+		Fac = clamp(Fac1, 0.0f, 1.0f);
+	else
+		Fac = 0.0f;
+	
+	return Fac;
+}
+
+CCL_NAMESPACE_END
+
diff --git a/intern/cycles/render/nodes.cpp b/intern/cycles/render/nodes.cpp
index e8476bfac4c..971b96e4a16 100644
--- a/intern/cycles/render/nodes.cpp
+++ b/intern/cycles/render/nodes.cpp
@@ -17,6 +17,7 @@
 #include "image.h"
 #include "nodes.h"
 #include "svm.h"
+#include "svm_math_util.h"
 #include "osl.h"
 #include "sky_model.h"
 
@@ -3682,9 +3683,24 @@ void MathNode::compile(SVMCompiler& compiler)
 	ShaderInput *value2_in = input("Value2");
 	ShaderOutput *value_out = output("Value");
 
+	compiler.stack_assign(value_out);
+
+	/* Optimize math node without links to a single value node. */
+	if(value1_in->link == NULL && value2_in->link == NULL) {
+		float optimized_value = svm_math((NodeMath)type_enum[type],
+		                                 value1_in->value.x,
+		                                 value2_in->value.x);
+		if(use_clamp) {
+			optimized_value = clamp(optimized_value, 0.0f, 1.0f);
+		}
+		compiler.add_node(NODE_VALUE_F,
+		                  __float_as_int(optimized_value),
+		                  value_out->stack_offset);
+		return;
+	}
+
 	compiler.stack_assign(value1_in);
 	compiler.stack_assign(value2_in);
-	compiler.stack_assign(value_out);
 
 	compiler.add_node(NODE_MATH, type_enum[type], value1_in->stack_offset, value2_in->stack_offset);
 	compiler.add_node(NODE_MATH, value_out->stack_offset);