text: //////////////////////////////////////////////////////////////////////////////////
  /// OpenGL Image (gli.g-truc.net)
  ///
  /// Copyright (c) 2008 - 2015 G-Truc Creation (www.g-truc.net)
  /// 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.
  ///
  /// @ref core
  /// @file gli/core/texture_2d.cpp
  /// @date 2011-10-11 / 2013-11-25
  /// @author Christophe Riccio
  ///////////////////////////////////////////////////////////////////////////////////
  
  #include <gli/sampler2d.hpp>
  #include <gli/comparison.hpp>
  #include <glm/gtx/component_wise.hpp>
  #include <glm/gtc/epsilon.hpp>
  #include <ctime>
  #include <limits>
  #include <array>
  
  namespace load
  {
  	int test()
  	{
  		int Error(0);
  
  		gli::texture2D Texture(gli::FORMAT_RGBA8_UNORM, gli::texture2D::dim_type(4, 2), 1);
  		*(Texture.data<glm::u8vec4>() + 0) = glm::u8vec4(255,   0,   0, 255);
  		*(Texture.data<glm::u8vec4>() + 1) = glm::u8vec4(255, 128,   0, 255);
  		*(Texture.data<glm::u8vec4>() + 2) = glm::u8vec4(255, 255,   0, 255);
  		*(Texture.data<glm::u8vec4>() + 3) = glm::u8vec4(128, 255,   0, 255);
  		*(Texture.data<glm::u8vec4>() + 4) = glm::u8vec4(  0, 255,   0, 255);
  		*(Texture.data<glm::u8vec4>() + 5) = glm::u8vec4(  0, 255, 255, 255);
  		*(Texture.data<glm::u8vec4>() + 6) = glm::u8vec4(  0,   0, 255, 255);
  		*(Texture.data<glm::u8vec4>() + 7) = glm::u8vec4(255,   0, 255, 255);
  
  		glm::u8vec4 Data0 = Texture.load<glm::u8vec4>(gli::texture2D::dim_type(0, 0), 0);
  		glm::u8vec4 Data1 = Texture.load<glm::u8vec4>(gli::texture2D::dim_type(1, 0), 0);
  		glm::u8vec4 Data2 = Texture.load<glm::u8vec4>(gli::texture2D::dim_type(2, 0), 0);
  		glm::u8vec4 Data3 = Texture.load<glm::u8vec4>(gli::texture2D::dim_type(3, 0), 0);
  		glm::u8vec4 Data4 = Texture.load<glm::u8vec4>(gli::texture2D::dim_type(0, 1), 0);
  		glm::u8vec4 Data5 = Texture.load<glm::u8vec4>(gli::texture2D::dim_type(1, 1), 0);
  		glm::u8vec4 Data6 = Texture.load<glm::u8vec4>(gli::texture2D::dim_type(2, 1), 0);
  		glm::u8vec4 Data7 = Texture.load<glm::u8vec4>(gli::texture2D::dim_type(3, 1), 0);
  
  		Error += Data0 == glm::u8vec4(255,   0,   0, 255) ? 0 : 1;
  		Error += Data1 == glm::u8vec4(255, 128,   0, 255) ? 0 : 1;
  		Error += Data2 == glm::u8vec4(255, 255,   0, 255) ? 0 : 1;
  		Error += Data3 == glm::u8vec4(128, 255,   0, 255) ? 0 : 1;
  		Error += Data4 == glm::u8vec4(  0, 255,   0, 255) ? 0 : 1;
  		Error += Data5 == glm::u8vec4(  0, 255, 255, 255) ? 0 : 1;
  		Error += Data6 == glm::u8vec4(  0,   0, 255, 255) ? 0 : 1;
  		Error += Data7 == glm::u8vec4(255,   0, 255, 255) ? 0 : 1;
  
  		return Error;
  	}
  }//namespace load
  
  /*
  namespace sampler
  {
  	int test()
  	{
  		int Error(0);
  
  		gli::texture2D::dim_type const Size(512);
  		gli::texture2D TextureA(gli::FORMAT_RGBA8_UNORM, Size, 1);
  
  		{
  			std::clock_t TimeStart = std::clock();
  
  			for(std::size_t y = 0; y < Size.y; ++y)
  			for(std::size_t x = 0; x < Size.x; ++x)
  			{
  				gli::texel_write(TextureA, gli::texture2D::dim_type(x, y), 0, glm::u8vec4(255, 128,   0, 255));
  			}
  
  			std::clock_t TimeEnd = std::clock();
  
  			printf("texel_write(texture2D) - Time: %lu\n", TimeEnd - TimeStart);
  		}
  
  		gli::texture2D TextureB(gli::FORMAT_RGBA8_UNORM, Size, 1);
  
  		{
  			gli::sampler2D<float> Sampler(TextureB, gli::WRAP_CLAMP_TO_EDGE, gli::FILTER_LINEAR, gli::FILTER_LINEAR, glm::vec4(0.0f, 0.5f, 1.0f, 1.0f));
  
  			{
  				std::clock_t TimeStart = std::clock();
  
  				for(std::size_t y = 0; y < Size.y; ++y)
  				for(std::size_t x = 0; x < Size.x; ++x)
  				{
  					Sampler.texel_write<glm::tvec4, glm::u8>(gli::texture2D::dim_type(x, y), 0, glm::vec4(1.0f, 0.5f, 0.0f, 1.0f));
  				}
  
  				std::clock_t TimeEnd = std::clock();
  
  				printf("sampler2D::texel_write - Time: %lu\n", TimeEnd - TimeStart);
  			}
  
  			{
  				std::clock_t TimeStart = std::clock();
  
  				for(float y = -0.5f; y < 1.5f; y += 0.025f)
  				for(float x = -0.5f; x < 1.5f; x += 0.025f)
  				{
  					glm::vec4 ColorA = Sampler.texture_lod<glm::tvec4, glm::u8>(gli::texture2D::texcoord_type(x, y), 0.0f);
  					Error += glm::all(glm::equal(ColorA, glm::vec4(1.0f, 0.5f, 0.0f, 1.0f))) ? 0 : 1;
  				}
  
  				std::clock_t TimeEnd = std::clock();
  
  				printf("sampler2D::texture_lod - Time: %lu\n", TimeEnd - TimeStart);
  			}
  		}
  
  		Error += TextureA == TextureB ? 0 : 1;
  
  		return Error;
  	}
  }//namespace sampler
  */
  
  namespace texture_lod
  {
  	int test()
  	{
  		int Error = 0;
  
  		{
  			gli::texture2D Texture(gli::FORMAT_RGBA8_UNORM, gli::texture2D::dim_type(4), 1);
  			Texture.clear(gli::u8vec4(0, 0, 0, 255));
  			Texture.store(gli::dim2_t(0, 0), 0, gli::u8vec4(255, 127,   0, 255));
  			Texture.store(gli::dim2_t(1, 0), 0, gli::u8vec4(255, 127,   0, 255));
  			Texture.store(gli::dim2_t(0, 1), 0, gli::u8vec4(255, 127,   0, 255));
  			Texture.store(gli::dim2_t(1, 1), 0, gli::u8vec4(255, 127,   0, 255));
  			Texture.store(gli::dim2_t(2, 2), 0, gli::u8vec4(  0, 127, 255, 255));
  			Texture.store(gli::dim2_t(3, 2), 0, gli::u8vec4(  0, 127, 255, 255));
  			Texture.store(gli::dim2_t(2, 3), 0, gli::u8vec4(  0, 127, 255, 255));
  			Texture.store(gli::dim2_t(3, 3), 0, gli::u8vec4(  0, 127, 255, 255));
  
  			gli::sampler2D<float> Sampler(Texture, gli::WRAP_CLAMP_TO_EDGE, gli::FILTER_LINEAR, gli::FILTER_LINEAR, gli::vec4(1.0f, 0.5f, 0.0f, 1.0f));
  
  			gli::vec4 SampleA = Sampler.texture_lod(gli::fsampler2D::samplecoord_type(0.25f), 0.0f);
  			Error += gli::all(gli::epsilonEqual(SampleA, gli::vec4(1.0f, 0.5f, 0.0f, 1.0f), 0.01f)) ? 0 : 1;
  
  			gli::vec4 SampleB = Sampler.texture_lod(gli::fsampler2D::samplecoord_type(0.8f), 0.0f);
  			Error += gli::all(gli::epsilonEqual(SampleB, gli::vec4(0.0f, 0.5f, 1.0f, 1.0f), 0.01f)) ? 0 : 1;
  
  			gli::vec4 SampleC = Sampler.texture_lod(gli::fsampler2D::samplecoord_type(0.20f, 0.8f), 0.0f);
  			Error += gli::all(gli::epsilonEqual(SampleC, gli::vec4(0.0f, 0.0f, 0.0f, 1.0f), 0.01f)) ? 0 : 1;
  		}
  
  		return Error;
  	}
  }//namespace texture_lod
  
  namespace sampler_type
  {
  	int test()
  	{
  		int Error = 0;
  
  		{
  			gli::texture2D Texture(gli::FORMAT_RGBA8_UNORM, gli::texture2D::dim_type(4), 1);
  			gli::sampler2D<float> Sampler(Texture, gli::WRAP_CLAMP_TO_EDGE, gli::FILTER_LINEAR, gli::FILTER_LINEAR);
  		}
  
  		{
  			gli::texture2D Texture(gli::FORMAT_RGBA8_UNORM, gli::texture2D::dim_type(4), 1);
  			gli::sampler2D<double> Sampler(Texture, gli::WRAP_CLAMP_TO_EDGE, gli::FILTER_LINEAR, gli::FILTER_LINEAR);
  		}
  
  		{
  			gli::texture2D Texture(gli::FORMAT_RGBA8_UNORM, gli::texture2D::dim_type(4), 1);
  			gli::sampler2D<int> Sampler(Texture, gli::WRAP_CLAMP_TO_EDGE, gli::FILTER_LINEAR, gli::FILTER_LINEAR);
  		}
  
  		return Error;
  	}
  }//namespace sampler_type
  
  int main()
  {
  	int Error(0);
  
  	Error += texture_lod::test();
  	Error += load::test();
  	Error += sampler_type::test();
  
  	return Error;
  }
  
  