File indexing completed on 2024-05-12 05:31:43

 /*
     KWin - the KDE window manager
     This file is part of the KDE project.
 
     SPDX-FileCopyrightText: 2006-2007 Rivo Laks <rivolaks@hot.ee>
     SPDX-FileCopyrightText: 2010, 2011 Martin Gräßlin <mgraesslin@kde.org>
     SPDX-FileCopyrightText: 2023 Xaver Hugl <xaver.hugl@kde.org>
 
     SPDX-License-Identifier: GPL-2.0-or-later
 */
 
 #include "opengl/glutils.h"
 #include "glplatform.h"
 #include "gltexture_p.h"
 #include "utils/common.h"
 
 namespace KWin
 {
 
 static QList<QByteArray> glExtensions;
 
 // Functions
 
 static void initDebugOutput()
 {
     const bool have_KHR_debug = hasGLExtension(QByteArrayLiteral("GL_KHR_debug"));
     const bool have_ARB_debug = hasGLExtension(QByteArrayLiteral("GL_ARB_debug_output"));
     if (!have_KHR_debug && !have_ARB_debug) {
         return;
     }
 
     if (!have_ARB_debug) {
         // if we don't have ARB debug, but only KHR debug we need to verify whether the context is a debug context
         // it should work without as well, but empirical tests show: no it doesn't
         if (GLPlatform::instance()->isGLES()) {
             if (!hasGLVersion(3, 2)) {
                 // empirical data shows extension doesn't work
                 return;
             }
         } else if (!hasGLVersion(3, 0)) {
             return;
         }
         // can only be queried with either OpenGL >= 3.0 or OpenGL ES of at least 3.1
         GLint value = 0;
         glGetIntegerv(GL_CONTEXT_FLAGS, &value);
         if (!(value & GL_CONTEXT_FLAG_DEBUG_BIT)) {
             return;
         }
     }
 
     // Set the callback function
     auto callback = [](GLenum source, GLenum type, GLuint id,
                        GLenum severity, GLsizei length,
                        const GLchar *message,
                        const GLvoid *userParam) {
         while (length && std::isspace(message[length - 1])) {
             --length;
         }
 
         switch (type) {
         case GL_DEBUG_TYPE_ERROR:
         case GL_DEBUG_TYPE_UNDEFINED_BEHAVIOR:
             qCWarning(KWIN_OPENGL, "%#x: %.*s", id, length, message);
             break;
 
         case GL_DEBUG_TYPE_OTHER:
         case GL_DEBUG_TYPE_DEPRECATED_BEHAVIOR:
         case GL_DEBUG_TYPE_PORTABILITY:
         case GL_DEBUG_TYPE_PERFORMANCE:
         default:
             qCDebug(KWIN_OPENGL, "%#x: %.*s", id, length, message);
             break;
         }
     };
 
     glDebugMessageCallback(callback, nullptr);
 
     // This state exists only in GL_KHR_debug
     if (have_KHR_debug) {
         glEnable(GL_DEBUG_OUTPUT);
     }
 
     if (qEnvironmentVariableIntValue("KWIN_GL_DEBUG")) {
         // Enable all debug messages
         glDebugMessageControl(GL_DONT_CARE, GL_DONT_CARE, GL_DONT_CARE, 0, nullptr, GL_TRUE);
         // Insert a test message
         const QByteArray message = QByteArrayLiteral("OpenGL debug output initialized");
         glDebugMessageInsert(GL_DEBUG_SOURCE_APPLICATION, GL_DEBUG_TYPE_OTHER, 0,
                              GL_DEBUG_SEVERITY_LOW, message.length(), message.constData());
     } else {
         // Only enable error messages
         glDebugMessageControl(GL_DONT_CARE, GL_DEBUG_TYPE_ERROR, GL_DONT_CARE, 0, nullptr, GL_TRUE);
         glDebugMessageControl(GL_DONT_CARE, GL_DEBUG_TYPE_UNDEFINED_BEHAVIOR, GL_DONT_CARE, 0, nullptr, GL_TRUE);
     }
 }
 
 void initGL(const std::function<resolveFuncPtr(const char *)> &resolveFunction)
 {
     // Get list of supported OpenGL extensions
     if (hasGLVersion(3, 0)) {
         int count;
         glGetIntegerv(GL_NUM_EXTENSIONS, &count);
 
         for (int i = 0; i < count; i++) {
             const QByteArray name = (const char *)glGetStringi(GL_EXTENSIONS, i);
             glExtensions << name;
         }
     } else {
         glExtensions = QByteArray((const char *)glGetString(GL_EXTENSIONS)).split(' ');
     }
 
     // handle OpenGL extensions functions
     glResolveFunctions(resolveFunction);
 
     initDebugOutput();
 
     GLTexturePrivate::initStatic();
     GLFramebuffer::initStatic();
     GLVertexBuffer::initStatic();
 }
 
 void cleanupGL()
 {
     ShaderManager::cleanup();
     GLTexturePrivate::cleanup();
     GLFramebuffer::cleanup();
     GLVertexBuffer::cleanup();
     GLPlatform::cleanup();
 
     glExtensions.clear();
 }
 
 bool hasGLVersion(int major, int minor, int release)
 {
     return GLPlatform::instance()->glVersion() >= Version(major, minor, release);
 }
 
 bool hasGLExtension(const QByteArray &extension)
 {
     return glExtensions.contains(extension);
 }
 
 QList<QByteArray> openGLExtensions()
 {
     return glExtensions;
 }
 
 static QString formatGLError(GLenum err)
 {
     switch (err) {
     case GL_NO_ERROR:
         return QStringLiteral("GL_NO_ERROR");
     case GL_INVALID_ENUM:
         return QStringLiteral("GL_INVALID_ENUM");
     case GL_INVALID_VALUE:
         return QStringLiteral("GL_INVALID_VALUE");
     case GL_INVALID_OPERATION:
         return QStringLiteral("GL_INVALID_OPERATION");
     case GL_STACK_OVERFLOW:
         return QStringLiteral("GL_STACK_OVERFLOW");
     case GL_STACK_UNDERFLOW:
         return QStringLiteral("GL_STACK_UNDERFLOW");
     case GL_OUT_OF_MEMORY:
         return QStringLiteral("GL_OUT_OF_MEMORY");
     default:
         return QLatin1String("0x") + QString::number(err, 16);
     }
 }
 
 bool checkGLError(const char *txt)
 {
     GLenum err = glGetError();
     if (err == GL_CONTEXT_LOST) {
         qCWarning(KWIN_OPENGL) << "GL error: context lost";
         return true;
     }
     bool hasError = false;
     while (err != GL_NO_ERROR) {
         qCWarning(KWIN_OPENGL) << "GL error (" << txt << "): " << formatGLError(err);
         hasError = true;
         err = glGetError();
         if (err == GL_CONTEXT_LOST) {
             qCWarning(KWIN_OPENGL) << "GL error: context lost";
             break;
         }
     }
     return hasError;
 }
 
 } // namespace