kwin/glxbackend.cpp

/********************************************************************
 KWin - the KDE window manager
 This file is part of the KDE project.

Copyright (C) 2006 Lubos Lunak <l.lunak@kde.org>
Copyright (C) 2012 Martin Gräßlin <mgraesslin@kde.org>

Based on glcompmgr code by Felix Bellaby.
Using code from Compiz and Beryl.

This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program.  If not, see <http://www.gnu.org/licenses/>.
*********************************************************************/

// TODO: cmake magic
#ifndef KWIN_HAVE_OPENGLES
// own
#include "glxbackend.h"
// kwin
#include "options.h"
#include "utils.h"
#include "overlaywindow.h"
// kwin libs
#include <kwinglplatform.h>
// KDE
#include <KDE/KDebug>
#include <KDE/KXErrorHandler>

namespace KWin
{
GlxBackend::GlxBackend()
    : OpenGLBackend()
    , glxbuffer(None)
{
    init();
}


GlxBackend::~GlxBackend()
{
    // TODO: cleanup in error case
    // do cleanup after initBuffer()
    cleanupGL();
    glXMakeCurrent(display(), None, NULL);
    glXDestroyContext(display(), ctxbuffer);
    if (overlayWindow()->window()) {
        if (hasGLXVersion(1, 3))
            glXDestroyWindow(display(), glxbuffer);
        XDestroyWindow(display(), buffer);
        overlayWindow()->destroy();
    } else {
        glXDestroyPixmap(display(), glxbuffer);
        XFreeGC(display(), gcroot);
        XFreePixmap(display(), buffer);
    }
    checkGLError("Cleanup");
}

void GlxBackend::init()
{
    initGLX();
    // check for FBConfig support
    if (!hasGLExtension("GLX_SGIX_fbconfig") || !glXGetFBConfigAttrib || !glXGetFBConfigs ||
            !glXGetVisualFromFBConfig || !glXCreatePixmap || !glXDestroyPixmap ||
            !glXCreateWindow || !glXDestroyWindow) {
        setFailed("GLX_SGIX_fbconfig or required GLX functions missing");
        return; // error
    }
    if (!initDrawableConfigs()) {
        setFailed("Could not initialize the drawable configs");
        return;
    }
    if (!initBuffer()) {
        setFailed("Could not initialize the buffer");
        return;
    }
    if (!initRenderingContext()) {
        setFailed("Could not initialize rendering context");
        return;
    }
    // Initialize OpenGL
    GLPlatform *glPlatform = GLPlatform::instance();
    glPlatform->detect();
    glPlatform->printResults();
    initGL();
    // Check whether certain features are supported
    if (options->isGlVSync()) {
        if (glXGetVideoSync && glXSwapInterval && glXIsDirect(display(), ctxbuffer)) {
            unsigned int sync;
            if (glXGetVideoSync(&sync) == 0) {
                if (glXWaitVideoSync(1, 0, &sync) == 0) {
                    // NOTICE at this time we should actually check whether we can successfully
                    // deactivate the swapInterval "glXSwapInterval(0) == 0"
                    // (because we don't actually want it active unless we explicitly run a glXSwapBuffers)
                    // However mesa/dri will return a range error (6) because deactivating the
                    // swapinterval (as of today) seems completely unsupported
                    setHasWaitSync(true);
                    glXSwapInterval(0);
                }
                else
                    qWarning() << "NO VSYNC! glXWaitVideoSync(1,0,&uint) isn't 0 but" << glXWaitVideoSync(1, 0, &sync);
            } else
                qWarning() << "NO VSYNC! glXGetVideoSync(&uint) isn't 0 but" << glXGetVideoSync(&sync);
        } else
            qWarning() << "NO VSYNC! glXGetVideoSync, glXSwapInterval, glXIsDirect" <<
                        bool(glXGetVideoSync) << bool(glXSwapInterval) << glXIsDirect(display(), ctxbuffer);
    }
    setIsDirectRendering(bool(glXIsDirect(display(), ctxbuffer)));
    kDebug(1212) << "DB:" << isDoubleBuffer() << ", Direct:" << isDirectRendering() << endl;
}


bool GlxBackend::initRenderingContext()
{
    bool direct_rendering = options->isGlDirect();
    KXErrorHandler errs1;
    ctxbuffer = glXCreateNewContext(display(), fbcbuffer, GLX_RGBA_TYPE, NULL,
                                    direct_rendering ? GL_TRUE : GL_FALSE);
    bool failed = (ctxbuffer == NULL || !glXMakeCurrent(display(), glxbuffer, ctxbuffer));
    if (errs1.error(true))    // always check for error( having it all in one if () could skip
        failed = true;       // it due to evaluation short-circuiting
    if (failed) {
        if (!direct_rendering) {
            kDebug(1212).nospace() << "Couldn't initialize rendering context ("
                                   << KXErrorHandler::errorMessage(errs1.errorEvent()) << ")";
            return false;
        }
        glXMakeCurrent(display(), None, NULL);
        if (ctxbuffer != NULL)
            glXDestroyContext(display(), ctxbuffer);
        direct_rendering = false; // try again
        KXErrorHandler errs2;
        ctxbuffer = glXCreateNewContext(display(), fbcbuffer, GLX_RGBA_TYPE, NULL, GL_FALSE);
        bool failed = (ctxbuffer == NULL || !glXMakeCurrent(display(), glxbuffer, ctxbuffer));
        if (errs2.error(true))
            failed = true;
        if (failed) {
            kDebug(1212).nospace() << "Couldn't initialize rendering context ("
                                   << KXErrorHandler::errorMessage(errs2.errorEvent()) << ")";
            return false;
        }
    }
    return true;
}

bool GlxBackend::initBuffer()
{
    if (!initBufferConfigs())
        return false;
    if (fbcbuffer_db != NULL && overlayWindow()->create()) {
        // we have overlay, try to create double-buffered window in it
        fbcbuffer = fbcbuffer_db;
        XVisualInfo* visual = glXGetVisualFromFBConfig(display(), fbcbuffer);
        XSetWindowAttributes attrs;
        attrs.colormap = XCreateColormap(display(), rootWindow(), visual->visual, AllocNone);
        buffer = XCreateWindow(display(), overlayWindow()->window(), 0, 0, displayWidth(), displayHeight(),
                               0, visual->depth, InputOutput, visual->visual, CWColormap, &attrs);
        if (hasGLXVersion(1, 3))
            glxbuffer = glXCreateWindow(display(), fbcbuffer, buffer, NULL);
        else
            glxbuffer = buffer;
        overlayWindow()->setup(buffer);
        setDoubleBuffer(true);
        XFree(visual);
    } else if (fbcbuffer_nondb != NULL) {
        // cannot get any double-buffered drawable, will double-buffer using a pixmap
        fbcbuffer = fbcbuffer_nondb;
        XVisualInfo* visual = glXGetVisualFromFBConfig(display(), fbcbuffer);
        XGCValues gcattr;
        gcattr.subwindow_mode = IncludeInferiors;
        gcroot = XCreateGC(display(), rootWindow(), GCSubwindowMode, &gcattr);
        buffer = XCreatePixmap(display(), rootWindow(), displayWidth(), displayHeight(),
                               visual->depth);
        glxbuffer = glXCreatePixmap(display(), fbcbuffer, buffer, NULL);
        setDoubleBuffer(false);
        XFree(visual);
    } else {
        kError(1212) << "Couldn't create output buffer (failed to create overlay window?) !";
        return false; // error
    }
    int vis_buffer;
    glXGetFBConfigAttrib(display(), fbcbuffer, GLX_VISUAL_ID, &vis_buffer);
    XVisualInfo* visinfo_buffer = glXGetVisualFromFBConfig(display(), fbcbuffer);
    kDebug(1212) << "Buffer visual (depth " << visinfo_buffer->depth << "): 0x" << QString::number(vis_buffer, 16);
    XFree(visinfo_buffer);
    return true;
}

bool GlxBackend::initBufferConfigs()
{
    int cnt;
    GLXFBConfig *fbconfigs = glXGetFBConfigs(display(), DefaultScreen(display()), &cnt);
    fbcbuffer_db = NULL;
    fbcbuffer_nondb = NULL;

    for (int i = 0; i < 2; i++) {
        int back, stencil, depth, caveat, alpha;
        back = i > 0 ? INT_MAX : 1;
        stencil = INT_MAX;
        depth = INT_MAX;
        caveat = INT_MAX;
        alpha = 0;
        for (int j = 0; j < cnt; j++) {
            XVisualInfo *vi;
            int visual_depth;
            vi = glXGetVisualFromFBConfig(display(), fbconfigs[ j ]);
            if (vi == NULL)
                continue;
            visual_depth = vi->depth;
            XFree(vi);
            if (visual_depth != DefaultDepth(display(), DefaultScreen(display())))
                continue;
            int value;
            glXGetFBConfigAttrib(display(), fbconfigs[ j ],
                                 GLX_ALPHA_SIZE, &alpha);
            glXGetFBConfigAttrib(display(), fbconfigs[ j ],
                                 GLX_BUFFER_SIZE, &value);
            if (value != visual_depth && (value - alpha) != visual_depth)
                continue;
            glXGetFBConfigAttrib(display(), fbconfigs[ j ],
                                 GLX_RENDER_TYPE, &value);
            if (!(value & GLX_RGBA_BIT))
                continue;
            int back_value;
            glXGetFBConfigAttrib(display(), fbconfigs[ j ],
                                 GLX_DOUBLEBUFFER, &back_value);
            if (i > 0) {
                if (back_value > back)
                    continue;
            } else {
                if (back_value < back)
                    continue;
            }
            int stencil_value;
            glXGetFBConfigAttrib(display(), fbconfigs[ j ],
                                 GLX_STENCIL_SIZE, &stencil_value);
            if (stencil_value > stencil)
                continue;
            int depth_value;
            glXGetFBConfigAttrib(display(), fbconfigs[ j ],
                                 GLX_DEPTH_SIZE, &depth_value);
            if (depth_value > depth)
                continue;
            int caveat_value;
            glXGetFBConfigAttrib(display(), fbconfigs[ j ],
                                 GLX_CONFIG_CAVEAT, &caveat_value);
            if (caveat_value > caveat)
                continue;
            back = back_value;
            stencil = stencil_value;
            depth = depth_value;
            caveat = caveat_value;
            if (i > 0)
                fbcbuffer_nondb = fbconfigs[ j ];
            else
                fbcbuffer_db = fbconfigs[ j ];
        }
    }
    if (cnt)
        XFree(fbconfigs);
    if (fbcbuffer_db == NULL && fbcbuffer_nondb == NULL) {
        kError(1212) << "Couldn't find framebuffer configuration for buffer!";
        return false;
    }
    for (int i = 0; i <= 32; i++) {
        if (fbcdrawableinfo[ i ].fbconfig == NULL)
            continue;
        int vis_drawable = 0;
        glXGetFBConfigAttrib(display(), fbcdrawableinfo[ i ].fbconfig, GLX_VISUAL_ID, &vis_drawable);
        kDebug(1212) << "Drawable visual (depth " << i << "): 0x" << QString::number(vis_drawable, 16);
    }
    return true;
}

bool GlxBackend::initDrawableConfigs()
{
    int cnt;
    GLXFBConfig *fbconfigs = glXGetFBConfigs(display(), DefaultScreen(display()), &cnt);

    for (int i = 0; i <= 32; i++) {
        int back, stencil, depth, caveat, alpha, mipmap, rgba;
        back = INT_MAX;
        stencil = INT_MAX;
        depth = INT_MAX;
        caveat = INT_MAX;
        mipmap = 0;
        rgba = 0;
        fbcdrawableinfo[ i ].fbconfig = NULL;
        fbcdrawableinfo[ i ].bind_texture_format = 0;
        fbcdrawableinfo[ i ].texture_targets = 0;
        fbcdrawableinfo[ i ].y_inverted = 0;
        fbcdrawableinfo[ i ].mipmap = 0;
        for (int j = 0; j < cnt; j++) {
            XVisualInfo *vi;
            int visual_depth;
            vi = glXGetVisualFromFBConfig(display(), fbconfigs[ j ]);
            if (vi == NULL)
                continue;
            visual_depth = vi->depth;
            XFree(vi);
            if (visual_depth != i)
                continue;
            int value;
            glXGetFBConfigAttrib(display(), fbconfigs[ j ],
                                 GLX_ALPHA_SIZE, &alpha);
            glXGetFBConfigAttrib(display(), fbconfigs[ j ],
                                 GLX_BUFFER_SIZE, &value);
            if (value != i && (value - alpha) != i)
                continue;
            glXGetFBConfigAttrib(display(), fbconfigs[ j ],
                                 GLX_RENDER_TYPE, &value);
            if (!(value & GLX_RGBA_BIT))
                continue;
            value = 0;
            if (i == 32) {
                glXGetFBConfigAttrib(display(), fbconfigs[ j ],
                                     GLX_BIND_TO_TEXTURE_RGBA_EXT, &value);
                if (value) {
                    // TODO I think this should be set only after the config passes all tests
                    rgba = 1;
                    fbcdrawableinfo[ i ].bind_texture_format = GLX_TEXTURE_FORMAT_RGBA_EXT;
                }
            }
            if (!value) {
                if (rgba)
                    continue;
                glXGetFBConfigAttrib(display(), fbconfigs[ j ],
                                     GLX_BIND_TO_TEXTURE_RGB_EXT, &value);
                if (!value)
                    continue;
                fbcdrawableinfo[ i ].bind_texture_format = GLX_TEXTURE_FORMAT_RGB_EXT;
            }
            int back_value;
            glXGetFBConfigAttrib(display(), fbconfigs[ j ],
                                 GLX_DOUBLEBUFFER, &back_value);
            if (back_value > back)
                continue;
            int stencil_value;
            glXGetFBConfigAttrib(display(), fbconfigs[ j ],
                                 GLX_STENCIL_SIZE, &stencil_value);
            if (stencil_value > stencil)
                continue;
            int depth_value;
            glXGetFBConfigAttrib(display(), fbconfigs[ j ],
                                 GLX_DEPTH_SIZE, &depth_value);
            if (depth_value > depth)
                continue;
            int caveat_value;
            glXGetFBConfigAttrib(display(), fbconfigs[ j ],
                                 GLX_CONFIG_CAVEAT, &caveat_value);
            if (caveat_value > caveat)
                continue;
            // ok, config passed all tests, it's the best one so far
            fbcdrawableinfo[ i ].fbconfig = fbconfigs[ j ];
            caveat = caveat_value;
            back = back_value;
            stencil = stencil_value;
            depth = depth_value;
            mipmap = 0;
            glXGetFBConfigAttrib(display(), fbconfigs[ j ],
                                 GLX_BIND_TO_TEXTURE_TARGETS_EXT, &value);
            fbcdrawableinfo[ i ].texture_targets = value;
            glXGetFBConfigAttrib(display(), fbconfigs[ j ],
                                 GLX_Y_INVERTED_EXT, &value);
            fbcdrawableinfo[ i ].y_inverted = value;
            fbcdrawableinfo[ i ].mipmap = mipmap;
        }
    }
    if (cnt)
        XFree(fbconfigs);
    if (fbcdrawableinfo[ DefaultDepth(display(), DefaultScreen(display()))].fbconfig == NULL) {
        kError(1212) << "Couldn't find framebuffer configuration for default depth!";
        return false;
    }
    if (fbcdrawableinfo[ 32 ].fbconfig == NULL) {
        kError(1212) << "Couldn't find framebuffer configuration for depth 32 (no ARGB GLX visual)!";
        return false;
    }
    return true;
}

#define VSYNC_DEBUG 0

void GlxBackend::waitSync()
{
    // NOTE that vsync has no effect with indirect rendering
    if (waitSyncAvailable()) {
#if VSYNC_DEBUG
        startRenderTimer();
#endif
        uint sync;
#if 0
        // TODO: why precisely is this important?
        // the sync counter /can/ perform multiple steps during glXGetVideoSync & glXWaitVideoSync
        // but this only leads to waiting for two frames??!?
        glXGetVideoSync(&sync);
        glXWaitVideoSync(2, (sync + 1) % 2, &sync);
#else
        glXWaitVideoSync(1, 0, &sync);
#endif
#if VSYNC_DEBUG
        static int waitTime = 0, waitCounter = 0, doubleSyncCounter = 0;
        if (renderTime() > 11)
            ++doubleSyncCounter;
        waitTime += renderTime();
        ++waitCounter;
        if (waitCounter > 99)
        {
            qDebug() << "mean vsync wait time:" << float((float)waitTime / (float)waitCounter) << doubleSyncCounter << "/100";
            doubleSyncCounter = waitTime = waitCounter = 0;
        }
#endif
    }
    startRenderTimer(); // yes, the framerate shall be constant anyway.
}

#undef VSYNC_DEBUG

void GlxBackend::flushBuffer()
{
    if (isDoubleBuffer()) {
        if (lastMask() & Scene::PAINT_SCREEN_REGION) {
            waitSync();
            if (glXCopySubBuffer) {
                foreach (const QRect & r, lastDamage().rects()) {
                    // convert to OpenGL coordinates
                    int y = displayHeight() - r.y() - r.height();
                    glXCopySubBuffer(display(), glxbuffer, r.x(), y, r.width(), r.height());
                }
            } else {
                // if a shader is bound or the texture unit is enabled, copy pixels results in a black screen
                // therefore unbind the shader and restore after copying the pixels
                GLint shader = 0;
                if (ShaderManager::instance()->isShaderBound()) {
                    glGetIntegerv(GL_CURRENT_PROGRAM, &shader);
                    glUseProgram(0);
                }
                bool reenableTexUnit = false;
                if (glIsEnabled(GL_TEXTURE_2D)) {
                    glDisable(GL_TEXTURE_2D);
                    reenableTexUnit = true;
                }
                // no idea why glScissor() is used, but Compiz has it and it doesn't seem to hurt
                glEnable(GL_SCISSOR_TEST);
                glDrawBuffer(GL_FRONT);
                int xpos = 0;
                int ypos = 0;
                foreach (const QRect & r, lastDamage().rects()) {
                    // convert to OpenGL coordinates
                    int y = displayHeight() - r.y() - r.height();
                    // Move raster position relatively using glBitmap() rather
                    // than using glRasterPos2f() - the latter causes drawing
                    // artefacts at the bottom screen edge with some gfx cards
//                    glRasterPos2f( r.x(), r.y() + r.height());
                    glBitmap(0, 0, 0, 0, r.x() - xpos, y - ypos, NULL);
                    xpos = r.x();
                    ypos = y;
                    glScissor(r.x(), y, r.width(), r.height());
                    glCopyPixels(r.x(), y, r.width(), r.height(), GL_COLOR);
                }
                glBitmap(0, 0, 0, 0, -xpos, -ypos, NULL);   // move position back to 0,0
                glDrawBuffer(GL_BACK);
                glDisable(GL_SCISSOR_TEST);
                if (reenableTexUnit) {
                    glEnable(GL_TEXTURE_2D);
                }
                // rebind previously bound shader
                if (ShaderManager::instance()->isShaderBound()) {
                    glUseProgram(shader);
                }
            }
        } else {
            if (glXSwapInterval) {
                glXSwapInterval(options->isGlVSync() ? 1 : 0);
                glXSwapBuffers(display(), glxbuffer);
                glXSwapInterval(0);
                startRenderTimer(); // this is important so we don't assume to be loosing frames in the compositor timing calculation
            } else {
                waitSync();
                glXSwapBuffers(display(), glxbuffer);
            }
        }
        glXWaitGL();
    } else {
        glXWaitGL();
        if (lastMask() & Scene::PAINT_SCREEN_REGION)
            foreach (const QRect & r, lastDamage().rects())
                XCopyArea(display(), buffer, rootWindow(), gcroot, r.x(), r.y(), r.width(), r.height(), r.x(), r.y());
        else
            XCopyArea(display(), buffer, rootWindow(), gcroot, 0, 0, displayWidth(), displayHeight(), 0, 0);
    }
    XFlush(display());
}

void GlxBackend::screenGeometryChanged(const QSize &size)
{
    if (overlayWindow()->window() == None) {
        glXMakeCurrent(display(), None, NULL);
        glXDestroyPixmap(display(), glxbuffer);
        XFreePixmap(display(), buffer);
        XVisualInfo* visual = glXGetVisualFromFBConfig(display(), fbcbuffer);
        buffer = XCreatePixmap(display(), rootWindow(), size.width(), size.height(), visual->depth);
        XFree(visual);
        glxbuffer = glXCreatePixmap(display(), fbcbuffer, buffer, NULL);
        glXMakeCurrent(display(), glxbuffer, ctxbuffer);
        // TODO: there seems some bug, some clients become black until an eg. un/remap - could be a general pixmap buffer issue, though
    } else {
        glXMakeCurrent(display(), None, NULL); // deactivate context ////
        XMoveResizeWindow(display(), buffer, 0,0, size.width(), size.height());
        overlayWindow()->setup(buffer);
        XSync(display(), false);  // ensure X11 stuff has applied ////
        glXMakeCurrent(display(), glxbuffer, ctxbuffer); // reactivate context ////
        glViewport(0,0, size.width(), size.height()); // adjust viewport last - should btw. be superfluous on the Pixmap buffer - iirc glXCreatePixmap sets the context anyway. ////
    }
}

SceneOpenGL::TexturePrivate *GlxBackend::createBackendTexture(SceneOpenGL::Texture *texture)
{
    return new GlxTexture(texture, this);
}

void GlxBackend::prepareRenderingFrame()
{
    if (!lastDamage().isEmpty())
        flushBuffer();
    glXWaitX();
}

void GlxBackend::endRenderingFrame(int mask, const QRegion &damage)
{
    setLastDamage(damage);
    setLastMask(mask);
    glFlush();

    if (overlayWindow()->window())  // show the window only after the first pass,
        overlayWindow()->show();   // since that pass may take long
}


/********************************************************
 * GlxTexture
 *******************************************************/
GlxTexture::GlxTexture(SceneOpenGL::Texture *texture, GlxBackend *backend)
    : SceneOpenGL::TexturePrivate()
    , q(texture)
    , m_backend(backend)
    , m_glxpixmap(None)
{
}

GlxTexture::~GlxTexture()
{
    if (m_glxpixmap != None) {
        if (!options->isGlStrictBinding()) {
            glXReleaseTexImageEXT(display(), m_glxpixmap, GLX_FRONT_LEFT_EXT);
        }
        glXDestroyPixmap(display(), m_glxpixmap);
        m_glxpixmap = None;
    }
}

void GlxTexture::onDamage()
{
    if (options->isGlStrictBinding() && m_glxpixmap) {
        glXReleaseTexImageEXT(display(), m_glxpixmap, GLX_FRONT_LEFT_EXT);
        glXBindTexImageEXT(display(), m_glxpixmap, GLX_FRONT_LEFT_EXT, NULL);
    }
    GLTexturePrivate::onDamage();
}

void GlxTexture::findTarget()
{
    unsigned int new_target = 0;
    if (glXQueryDrawable && m_glxpixmap != None)
        glXQueryDrawable(display(), m_glxpixmap, GLX_TEXTURE_TARGET_EXT, &new_target);
    // HACK: this used to be a hack for Xgl.
    // without this hack the NVIDIA blob aborts when trying to bind a texture from
    // a pixmap icon
    if (new_target == 0) {
        if (GLTexture::NPOTTextureSupported() ||
            (isPowerOfTwo(m_size.width()) && isPowerOfTwo(m_size.height()))) {
            new_target = GLX_TEXTURE_2D_EXT;
        } else {
            new_target = GLX_TEXTURE_RECTANGLE_EXT;
        }
    }
    switch(new_target) {
    case GLX_TEXTURE_2D_EXT:
        m_target = GL_TEXTURE_2D;
        m_scale.setWidth(1.0f / m_size.width());
        m_scale.setHeight(1.0f / m_size.height());
        break;
    case GLX_TEXTURE_RECTANGLE_EXT:
        m_target = GL_TEXTURE_RECTANGLE_ARB;
        m_scale.setWidth(1.0f);
        m_scale.setHeight(1.0f);
        break;
    default:
        abort();
    }
}

bool GlxTexture::loadTexture(const Pixmap& pix, const QSize& size, int depth)
{
#ifdef CHECK_GL_ERROR
    checkGLError("TextureLoad1");
#endif
    if (pix == None || size.isEmpty() || depth < 1)
        return false;
    if (m_backend->fbcdrawableinfo[ depth ].fbconfig == NULL) {
        kDebug(1212) << "No framebuffer configuration for depth " << depth
                     << "; not binding pixmap" << endl;
        return false;
    }

    m_size = size;
    // new texture, or texture contents changed; mipmaps now invalid
    q->setDirty();

#ifdef CHECK_GL_ERROR
    checkGLError("TextureLoad2");
#endif
    // tfp mode, simply bind the pixmap to texture
    glGenTextures(1, &m_texture);
    // The GLX pixmap references the contents of the original pixmap, so it doesn't
    // need to be recreated when the contents change.
    // The texture may or may not use the same storage depending on the EXT_tfp
    // implementation. When options->glStrictBinding is true, the texture uses
    // a different storage and needs to be updated with a call to
    // glXBindTexImageEXT() when the contents of the pixmap has changed.
    int attrs[] = {
        GLX_TEXTURE_FORMAT_EXT, m_backend->fbcdrawableinfo[ depth ].bind_texture_format,
        GLX_MIPMAP_TEXTURE_EXT, m_backend->fbcdrawableinfo[ depth ].mipmap > 0,
        None, None, None
    };
    // Specifying the texture target explicitly is reported to cause a performance
    // regression with R300G (see bug #256654).
    if (GLPlatform::instance()->driver() != Driver_R300G) {
        if ((m_backend->fbcdrawableinfo[ depth ].texture_targets & GLX_TEXTURE_2D_BIT_EXT) &&
                (GLTexture::NPOTTextureSupported() ||
                  (isPowerOfTwo(size.width()) && isPowerOfTwo(size.height())))) {
            attrs[ 4 ] = GLX_TEXTURE_TARGET_EXT;
            attrs[ 5 ] = GLX_TEXTURE_2D_EXT;
        } else if (m_backend->fbcdrawableinfo[ depth ].texture_targets & GLX_TEXTURE_RECTANGLE_BIT_EXT) {
            attrs[ 4 ] = GLX_TEXTURE_TARGET_EXT;
            attrs[ 5 ] = GLX_TEXTURE_RECTANGLE_EXT;
        }
    }
    m_glxpixmap = glXCreatePixmap(display(), m_backend->fbcdrawableinfo[ depth ].fbconfig, pix, attrs);
#ifdef CHECK_GL_ERROR
    checkGLError("TextureLoadTFP1");
#endif
    findTarget();
    m_yInverted = m_backend->fbcdrawableinfo[ depth ].y_inverted ? true : false;
    m_canUseMipmaps = m_backend->fbcdrawableinfo[ depth ].mipmap > 0;
    q->setFilter(m_backend->fbcdrawableinfo[ depth ].mipmap > 0 ? GL_NEAREST_MIPMAP_LINEAR : GL_NEAREST);
    glBindTexture(m_target, m_texture);
#ifdef CHECK_GL_ERROR
    checkGLError("TextureLoadTFP2");
#endif
    glXBindTexImageEXT(display(), m_glxpixmap, GLX_FRONT_LEFT_EXT, NULL);
#ifdef CHECK_GL_ERROR
    checkGLError("TextureLoad0");
#endif
    unbind();
    return true;
}

OpenGLBackend *GlxTexture::backend()
{
    return m_backend;
}

} // namespace
#endif