text: /*
   * Copyright 2011-2015 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
  
  /* TODO(sergey): Think of making it more generic volume-type attribute
   * sampler.
   */
  ccl_device void svm_node_tex_voxel(
      KernelGlobals *kg, ShaderData *sd, float *stack, uint4 node, int *offset)
  {
    uint co_offset, density_out_offset, color_out_offset, space;
    svm_unpack_node_uchar4(node.z, &co_offset, &density_out_offset, &color_out_offset, &space);
  #ifdef __VOLUME__
    int id = node.y;
    float3 co = stack_load_float3(stack, co_offset);
    if (space == NODE_TEX_VOXEL_SPACE_OBJECT) {
      co = volume_normalized_position(kg, sd, co);
    }
    else {
      kernel_assert(space == NODE_TEX_VOXEL_SPACE_WORLD);
      Transform tfm;
      tfm.x = read_node_float(kg, offset);
      tfm.y = read_node_float(kg, offset);
      tfm.z = read_node_float(kg, offset);
      co = transform_point(&tfm, co);
    }
  
    float4 r = kernel_tex_image_interp_3d(kg, id, co.x, co.y, co.z, INTERPOLATION_NONE);
  #else
    float4 r = make_float4(0.0f, 0.0f, 0.0f, 0.0f);
  #endif
    if (stack_valid(density_out_offset))
      stack_store_float(stack, density_out_offset, r.w);
    if (stack_valid(color_out_offset))
      stack_store_float3(stack, color_out_offset, make_float3(r.x, r.y, r.z));
  }
  
  CCL_NAMESPACE_END
  