text: /**
   * Copyright (c) 2017 Melown Technologies SE
   *
   * 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.
   *
   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "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 HOLDER 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.
   */
  
  #include "../include/vts-browser/math.hpp"
  #include "obj.hpp"
  
  #include <geometry/parse-obj.hpp>
  
  namespace vts
  {
  
  void decodeObj(const Buffer &in, uint32 &outFaceMode,
                 Buffer &outVertices, Buffer &,
                 uint32 &vertices, uint32 &indices)
  {
      geometry::Obj obj;
      detail::BufferStream w(in);
      if (!obj.parse(w))
      {
          LOGTHROW(err1, std::runtime_error) << "failed to decode obj file";
      }
  
      // find face mode
      outFaceMode = 3;
      for (geometry::Obj::Facet &of : obj.facets)
      {
          int v[3];
          for (uint32 i = 0; i < 3; i++)
              v[i] = of.v[i];
          std::sort(v, v + 3);
          uint32 j = std::unique(v, v + 3) - v;
          outFaceMode = std::min(outFaceMode, j);
      }
  
      struct F
      {
          vec3f vertex;
          vec2f uvs;
      };
      outVertices = Buffer(obj.facets.size() * sizeof(F) * outFaceMode);
      F *fs = (F*)outVertices.data();
      for (auto &of : obj.facets)
      {
          for (uint32 i = 0; i < outFaceMode; i++)
          {
              fs->vertex = vecFromUblas<vec3f>(obj.vertices[of.v[i]]);
              if (of.t[i] >= 0)
                  fs->uvs = vecFromUblas<vec3f>(obj.texcoords[of.t[i]]).head(2);
              else
                  fs->uvs = vec2f(0, 0);
              fs++;
          }
      }
      vertices = obj.facets.size() * outFaceMode;
      indices = 0;
  }
  
  } // namespace vts
  