70 lines
2.8 KiB
C++
70 lines
2.8 KiB
C++
///////////////////////////////////////////////////////////////////////////////////////////////////
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// OpenGL Image Copyright (c) 2008 - 2011 G-Truc Creation (www.g-truc.net)
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///////////////////////////////////////////////////////////////////////////////////////////////////
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// Created : 2010-09-27
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// Updated : 2010-09-27
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// Licence : This source is under MIT License
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// File : gli/core/generate_mipmaps.inl
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///////////////////////////////////////////////////////////////////////////////////////////////////
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namespace gli
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{
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/*
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inline texture2D generateMipmaps
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(
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texture2D const & Image,
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texture2D::level_type const & BaseLevel
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)
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{
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assert(BaseLevel < Image.levels());
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texture2D::format_type Format = Image[BaseLevel].format();
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assert(Format == R8U || Format == RG8U || Format == RGB8U || Format == RGBA8U);
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texture2D::level_type Levels = std::size_t(glm::log2(float(glm::compMax(Image[0].dimensions())))) + 1;
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texture2D Result(Levels);
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for(texture2D::level_type Level = 0; Level <= BaseLevel; ++Level)
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Result[Level] = detail::duplicate(Image[Level]);
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for(texture2D::level_type Level = BaseLevel; Level < Levels - 1; ++Level)
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{
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std::size_t BaseWidth = Result[Level + 0].dimensions().x;
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texture2D::value_type * DataSrc = Result[Level + 0].data();
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texture2D::dimensions_type LevelDimensions = Result[Level + 0].dimensions() >> texture2D::dimensions_type(1);
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LevelDimensions = glm::max(LevelDimensions, texture2D::dimensions_type(1));
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texture2D::size_type Components = Result[Level + 0].components();
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texture2D::data_type DataDst(glm::compMul(LevelDimensions) * Components);
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for(std::size_t j = 0; j < LevelDimensions.y; ++j)
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for(std::size_t i = 0; i < LevelDimensions.x; ++i)
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for(std::size_t c = 0; c < Components; ++c)
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{
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std::size_t x = (i << 1);
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std::size_t y = (j << 1);
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std::size_t Index00 = ((x + 0) + (y + 0) * BaseWidth) * Components + c;
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std::size_t Index01 = ((x + 0) + (y + 1) * BaseWidth) * Components + c;
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std::size_t Index11 = ((x + 1) + (y + 1) * BaseWidth) * Components + c;
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std::size_t Index10 = ((x + 1) + (y + 0) * BaseWidth) * Components + c;
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glm::u32 Data00 = reinterpret_cast<texture2D::value_type*>(DataSrc)[Index00];
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glm::u32 Data01 = reinterpret_cast<texture2D::value_type*>(DataSrc)[Index01];
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glm::u32 Data11 = reinterpret_cast<texture2D::value_type*>(DataSrc)[Index11];
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glm::u32 Data10 = reinterpret_cast<texture2D::value_type*>(DataSrc)[Index10];
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texture2D::value_type Result = (Data00 + Data01 + Data11 + Data10) >> 2;
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texture2D::value_type * Data = reinterpret_cast<texture2D::value_type*>(DataDst.data());
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*(Data + ((i + j * LevelDimensions.x) * Components + c)) = Result;
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}
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Result[Level + 1] = image2D(LevelDimensions, Format, DataDst);
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}
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return Result;
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}
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*/
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}//namespace gli
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