text: // ----------------------------------------------------------------------------
  // -                        Open3D: www.open3d.org                            -
  // ----------------------------------------------------------------------------
  // The MIT License (MIT)
  //
  // Copyright (c) 2018 www.open3d.org
  //
  // Permission is hereby granted, free of charge, to any person obtaining a copy
  // of this software and associated documentation files (the "Software"), to deal
  // in the Software without restriction, including without limitation the rights
  // to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  // copies of the Software, and to permit persons to whom the Software is
  // furnished to do so, subject to the following conditions:
  //
  // The above copyright notice and this permission notice shall be included in
  // all copies or substantial portions of the Software.
  //
  // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  // FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
  // IN THE SOFTWARE.
  // ----------------------------------------------------------------------------
  
  #pragma once
  
  #include <Core/Geometry/Image.h>
  #include <Visualization/Shader/ShaderWrapper.h>
  
  namespace three {
  
  namespace glsl {
      
  class ImageMaskShader : public ShaderWrapper
  {
  public:
      ~ImageMaskShader() override { Release(); }
  
  protected:
      ImageMaskShader(const std::string &name) : ShaderWrapper(name) { Compile(); }
      
  protected:
      bool Compile() final;
      void Release() final;
      bool BindGeometry(const Geometry &geometry, const RenderOption &option,
              const ViewControl &view) final;
      bool RenderGeometry(const Geometry &geometry, const RenderOption &option,
              const ViewControl &view) final;
      void UnbindGeometry() final;
  
  protected:
      virtual bool PrepareRendering(const Geometry &geometry,
              const RenderOption &option, const ViewControl &view) = 0;
      virtual bool PrepareBinding(const Geometry &geometry,
              const RenderOption &option, const ViewControl &view,
              Image &image) = 0;
  
  protected:
      GLuint vertex_position_;
      GLuint vertex_position_buffer_;
      GLuint vertex_UV_;
      GLuint vertex_UV_buffer_;
      GLuint image_texture_;
      GLuint image_texture_buffer_;
      GLuint mask_color_;
      GLuint mask_alpha_;
      
      GLHelper::GLVector3f mask_color_data_;
      GLfloat mask_alpha_data_;
  };
  
  class ImageMaskShaderForImage : public ImageMaskShader
  {
  public:
      ImageMaskShaderForImage() : ImageMaskShader("ImageMaskShaderForImage") {}
  
  protected:
      virtual bool PrepareRendering(const Geometry &geometry,
              const RenderOption &option, const ViewControl &view) final;
      virtual bool PrepareBinding(const Geometry &geometry,
              const RenderOption &option, const ViewControl &view,
              Image &render_image) final;
  };
      
  }    // namespace three::glsl
  
  }    // namespace three
  