File indexing completed on 2024-05-12 05:31:41

 /*
     KWin - the KDE window manager
     This file is part of the KDE project.
 
     SPDX-FileCopyrightText: 2023 Xaver Hugl <xaver.hugl@gmail.com>
 
     SPDX-License-Identifier: GPL-2.0-or-later
 */
 #include "gllut.h"
 
 #include <vector>
 
 namespace KWin
 {
 
 GlLookUpTable::GlLookUpTable(GLuint handle, size_t size)
     : m_handle(handle)
     , m_size(size)
 {
 }
 
 GlLookUpTable::~GlLookUpTable()
 {
     glDeleteTextures(1, &m_handle);
 }
 
 GLuint GlLookUpTable::handle() const
 {
     return m_handle;
 }
 
 size_t GlLookUpTable::size() const
 {
     return m_size;
 }
 
 void GlLookUpTable::bind()
 {
     glBindTexture(GL_TEXTURE_2D, m_handle);
 }
 
 std::unique_ptr<GlLookUpTable> GlLookUpTable::create(const std::function<QVector3D(size_t value)> &func, size_t size)
 {
     GLuint handle = 0;
     glGenTextures(1, &handle);
     if (!handle) {
         return nullptr;
     }
     // this uses 2D textures because OpenGL ES doesn't support 1D textures
     glBindTexture(GL_TEXTURE_2D, handle);
     glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAX_LEVEL, 0);
     glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_LOD, 0);
     glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAX_LOD, 0);
     glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
     glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
     glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
     glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
     std::vector<float> data;
     data.reserve(4 * size);
     for (size_t i = 0; i < size; i++) {
         const auto color = func(i);
         data.push_back(color.x());
         data.push_back(color.y());
         data.push_back(color.z());
         data.push_back(1);
     }
     glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA16F, size, 1, 0, GL_RGBA, GL_FLOAT, data.data());
     glBindTexture(GL_TEXTURE_2D, 0);
     return std::make_unique<GlLookUpTable>(handle, size);
 }
 
 }