text: /* 
   * Copyright (c) 2018 NVIDIA CORPORATION. All rights reserved.
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions
   * are met:
   *  * Redistributions of source code must retain the above copyright
   *    notice, this list of conditions and the following disclaimer.
   *  * Redistributions in binary form must reproduce the above copyright
   *    notice, this list of conditions and the following disclaimer in the
   *    documentation and/or other materials provided with the distribution.
   *  * Neither the name of NVIDIA CORPORATION nor the names of its
   *    contributors may be used to endorse or promote products derived
   *    from this software without specific prior written permission.
   *
   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS ``AS IS'' AND ANY
   * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
   * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR
   * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
   * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
   * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
   * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
   * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
   * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
   * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
   */
  
  
  #pragma once
  
  #include <sutil.h>
  #include <Mesh.h>
  #include <optixu/optixpp_namespace.h>
  #include <optixu/optixu_matrix_namespace.h>
  
  
  //------------------------------------------------------------------------------
  //
  // OptiX mesh consisting of a single geometry instance with one or more
  // materials.
  //
  // Mesh buffer variables are set on Geometry node:
  //   vertex_buffer  : float3 vertex positions
  //   normal_buffer  : float3 per vertex normals, may be zero length 
  //   texcoord_buffer: float2 vertex texture coordinates, may be zero length
  //   index_buffer   : int3 indices shared by vertex, normal, texcoord buffers 
  //   material_buffer: int indices into material list
  //
  //------------------------------------------------------------------------------
  struct OptiXMesh
  {
    // Input
    optix::Context               context;       // required
    optix::Material              material;      // optional single matl override
  
    optix::Program               intersection;  // optional 
    optix::Program               bounds;        // optional
    
    optix::Program               closest_hit;   // optional multi matl override
    optix::Program               any_hit;       // optional
  
    // Output
    optix::GeometryInstance      geom_instance;
    optix::float3                bbox_min;
    optix::float3                bbox_max;
  
    int                          num_triangles;
  };
  
  
  SUTILAPI void loadMesh(
      const std::string&        filename,
      OptiXMesh&                mesh, 
      const optix::Matrix4x4&   load_xform = optix::Matrix4x4::identity()
      );
  