Shading: Rewrite Mapping node with dynamic inputs.

This patch rewrites the Mapping node to support dynamic inputs. The
Max and Min options have been removed. They can be added as Min and
Max Vector Math nodes manually.

Texture nodes still use the old matrix-based mapping. A new SVM node
`NODE_TEXTURE_MAPPING` has been added to preserve this functionality.
Similarly, in GLSL, a `mapping_mat4` function has been added.

Reviewers: brecht, JacquesLucke

1 files changed, 17 insertions, 0 deletions

diff --git a/intern/cycles/render/constant_fold.cpp b/intern/cycles/render/constant_fold.cpp
index 851d4b71df8..f3809ee8d80 100644
--- a/intern/cycles/render/constant_fold.cpp
+++ b/intern/cycles/render/constant_fold.cpp
@@ -429,4 +429,21 @@ void ConstantFolder::fold_vector_math(NodeVectorMathType type) const
   }
 }
 
+void ConstantFolder::fold_mapping(NodeMappingType type) const
+{
+  ShaderInput *vector_in = node->input("Vector");
+  ShaderInput *location_in = node->input("Location");
+  ShaderInput *rotation_in = node->input("Rotation");
+  ShaderInput *scale_in = node->input("Scale");
+
+  if (is_zero(scale_in)) {
+    make_zero();
+  }
+  else if ((is_zero(location_in) || type == NODE_MAPPING_TYPE_VECTOR ||
+            type == NODE_MAPPING_TYPE_NORMAL) &&
+           is_zero(rotation_in) && is_one(scale_in)) {
+    try_bypass_or_make_constant(vector_in);
+  }
+}
+
 CCL_NAMESPACE_END