Shading: Add invert option to Vector Rotate Node

Checkbox to invert rotation angle, suggested by @simonthommes

Differential Revision: https://developer.blender.org/D6932

1 files changed, 39 insertions, 32 deletions

diff --git a/intern/cycles/kernel/svm/svm_vector_rotate.h b/intern/cycles/kernel/svm/svm_vector_rotate.h
index 0dc0e223f41..79a4ec2c40e 100644
--- a/intern/cycles/kernel/svm/svm_vector_rotate.h
+++ b/intern/cycles/kernel/svm/svm_vector_rotate.h
@@ -25,45 +25,52 @@ ccl_device void svm_node_vector_rotate(ShaderData *sd,
                                        uint result_stack_offset)
 {
   uint type, vector_stack_offset, rotation_stack_offset, center_stack_offset, axis_stack_offset,
-      angle_stack_offset;
+      angle_stack_offset, invert;
 
-  svm_unpack_node_uchar3(input_stack_offsets, &type, &vector_stack_offset, &rotation_stack_offset);
+  svm_unpack_node_uchar4(
+      input_stack_offsets, &type, &vector_stack_offset, &rotation_stack_offset, &invert);
   svm_unpack_node_uchar3(
       axis_stack_offsets, &center_stack_offset, &axis_stack_offset, &angle_stack_offset);
 
-  float3 vector = stack_load_float3(stack, vector_stack_offset);
-  float3 center = stack_load_float3(stack, center_stack_offset);
-  float3 result = make_float3(0.0f, 0.0f, 0.0f);
+  if (stack_valid(result_stack_offset)) {
 
-  if (type == NODE_VECTOR_ROTATE_TYPE_EULER_XYZ) {
-    float3 rotation = stack_load_float3(stack, rotation_stack_offset);  // Default XYZ.
-    Transform rotationTransform = euler_to_transform(rotation);
-    result = transform_direction(&rotationTransform, vector - center) + center;
-  }
-  else {
-    float3 axis;
-    switch (type) {
-      case NODE_VECTOR_ROTATE_TYPE_AXIS_X:
-        axis = make_float3(1.0f, 0.0f, 0.0f);
-        break;
-      case NODE_VECTOR_ROTATE_TYPE_AXIS_Y:
-        axis = make_float3(0.0f, 1.0f, 0.0f);
-        break;
-      case NODE_VECTOR_ROTATE_TYPE_AXIS_Z:
-        axis = make_float3(0.0f, 0.0f, 1.0f);
-        break;
-      default:
-        axis = normalize(stack_load_float3(stack, axis_stack_offset));
-        break;
+    float3 vector = stack_load_float3(stack, vector_stack_offset);
+    float3 center = stack_load_float3(stack, center_stack_offset);
+    float3 result = make_float3(0.0f, 0.0f, 0.0f);
+
+    if (type == NODE_VECTOR_ROTATE_TYPE_EULER_XYZ) {
+      float3 rotation = stack_load_float3(stack, rotation_stack_offset);  // Default XYZ.
+      Transform rotationTransform = euler_to_transform(rotation);
+      if (invert) {
+        result = transform_direction_transposed(&rotationTransform, vector - center) + center;
+      }
+      else {
+        result = transform_direction(&rotationTransform, vector - center) + center;
+      }
+    }
+    else {
+      float3 axis;
+      switch (type) {
+        case NODE_VECTOR_ROTATE_TYPE_AXIS_X:
+          axis = make_float3(1.0f, 0.0f, 0.0f);
+          break;
+        case NODE_VECTOR_ROTATE_TYPE_AXIS_Y:
+          axis = make_float3(0.0f, 1.0f, 0.0f);
+          break;
+        case NODE_VECTOR_ROTATE_TYPE_AXIS_Z:
+          axis = make_float3(0.0f, 0.0f, 1.0f);
+          break;
+        default:
+          axis = normalize(stack_load_float3(stack, axis_stack_offset));
+          break;
+      }
+      float angle = stack_load_float(stack, angle_stack_offset);
+      angle = invert ? -angle : angle;
+      result = (len_squared(axis) != 0.0f) ?
+                   rotate_around_axis(vector - center, axis, angle) + center :
+                   vector;
     }
-    float angle = stack_load_float(stack, angle_stack_offset);
-    result = (len_squared(axis) != 0.0f) ?
-                 rotate_around_axis(vector - center, axis, angle) + center :
-                 vector;
-  }
 
-  /* Output */
-  if (stack_valid(result_stack_offset)) {
     stack_store_float3(stack, result_stack_offset, result);
   }
 }