kwin/plugins/platforms/x11/common/eglonxbackend.cpp
Martin Gräßlin 702b84b925 Move the EglOnXBackend to the x11 platforms
Summary:
The EglOnXBackend is no longer needed in the core. It's only needed by
the two x11 platform plugins. To best share it, it's moved into a common
directory and compiled into a static library which in turn is linked by
the two plugins.

Reviewers: #plasma

Subscribers: plasma-devel

Projects: #plasma

Differential Revision: https://phabricator.kde.org/D1413
2016-04-15 09:15:20 +02:00

488 lines
16 KiB
C++

/********************************************************************
KWin - the KDE window manager
This file is part of the KDE project.
Copyright (C) 2010, 2012 Martin Gräßlin <mgraesslin@kde.org>
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/>.
*********************************************************************/
#include "eglonxbackend.h"
// kwin
#include "main.h"
#include "options.h"
#include "overlaywindow.h"
#include "screens.h"
#include "xcbutils.h"
// kwin libs
#include <kwinglplatform.h>
// Qt
#include <QDebug>
#include <QOpenGLContext>
// system
#include <unistd.h>
Q_LOGGING_CATEGORY(KWIN_CORE, "kwin_core", QtCriticalMsg)
namespace KWin
{
EglOnXBackend::EglOnXBackend()
: AbstractEglBackend()
, m_overlayWindow(new OverlayWindow())
, surfaceHasSubPost(0)
, m_bufferAge(0)
, m_usesOverlayWindow(true)
, m_connection(connection())
, m_x11Display(display())
, m_rootWindow(rootWindow())
, m_x11ScreenNumber(kwinApp()->x11ScreenNumber())
{
// Egl is always direct rendering
setIsDirectRendering(true);
}
EglOnXBackend::EglOnXBackend(xcb_connection_t *connection, Display *display, xcb_window_t rootWindow, int screenNumber, xcb_window_t renderingWindow)
: AbstractEglBackend()
, m_overlayWindow(nullptr)
, surfaceHasSubPost(0)
, m_bufferAge(0)
, m_usesOverlayWindow(false)
, m_connection(connection)
, m_x11Display(display)
, m_rootWindow(rootWindow)
, m_x11ScreenNumber(screenNumber)
, m_renderingWindow(renderingWindow)
{
// Egl is always direct rendering
setIsDirectRendering(true);
}
static bool gs_tripleBufferUndetected = true;
static bool gs_tripleBufferNeedsDetection = false;
EglOnXBackend::~EglOnXBackend()
{
if (isFailed() && m_overlayWindow) {
m_overlayWindow->destroy();
}
cleanup();
gs_tripleBufferUndetected = true;
gs_tripleBufferNeedsDetection = false;
if (m_overlayWindow) {
if (overlayWindow()->window()) {
overlayWindow()->destroy();
}
delete m_overlayWindow;
}
}
void EglOnXBackend::init()
{
qputenv("EGL_PLATFORM", "x11");
initEGL(); // required to toggle
initBufferAge(); // EGL_SWAP_BEHAVIOR_PRESERVED_BIT
if (!initRenderingContext()) {
setFailed(QStringLiteral("Could not initialize rendering context"));
return;
}
initKWinGL();
if (!hasGLExtension(QByteArrayLiteral("EGL_KHR_image")) &&
(!hasGLExtension(QByteArrayLiteral("EGL_KHR_image_base")) ||
!hasGLExtension(QByteArrayLiteral("EGL_KHR_image_pixmap")))) {
setFailed(QStringLiteral("Required support for binding pixmaps to EGLImages not found, disabling compositing"));
return;
}
if (!hasGLExtension(QByteArrayLiteral("GL_OES_EGL_image"))) {
setFailed(QStringLiteral("Required extension GL_OES_EGL_image not found, disabling compositing"));
return;
}
// check for EGL_NV_post_sub_buffer and whether it can be used on the surface
if (hasGLExtension(QByteArrayLiteral("EGL_NV_post_sub_buffer"))) {
if (eglQuerySurface(eglDisplay(), surface(), EGL_POST_SUB_BUFFER_SUPPORTED_NV, &surfaceHasSubPost) == EGL_FALSE) {
EGLint error = eglGetError();
if (error != EGL_SUCCESS && error != EGL_BAD_ATTRIBUTE) {
setFailed(QStringLiteral("query surface failed"));
return;
} else {
surfaceHasSubPost = EGL_FALSE;
}
}
}
initBufferAge();
setSyncsToVBlank(false);
setBlocksForRetrace(false);
gs_tripleBufferNeedsDetection = false;
m_swapProfiler.init();
if (surfaceHasSubPost) {
qCDebug(KWIN_CORE) << "EGL implementation and surface support eglPostSubBufferNV, let's use it";
if (options->glPreferBufferSwap() != Options::NoSwapEncourage) {
// check if swap interval 1 is supported
EGLint val;
eglGetConfigAttrib(eglDisplay(), config(), EGL_MAX_SWAP_INTERVAL, &val);
if (val >= 1) {
if (eglSwapInterval(eglDisplay(), 1)) {
qCDebug(KWIN_CORE) << "Enabled v-sync";
setSyncsToVBlank(true);
const QByteArray tripleBuffer = qgetenv("KWIN_TRIPLE_BUFFER");
if (!tripleBuffer.isEmpty()) {
setBlocksForRetrace(qstrcmp(tripleBuffer, "0") == 0);
gs_tripleBufferUndetected = false;
}
gs_tripleBufferNeedsDetection = gs_tripleBufferUndetected;
}
} else {
qCWarning(KWIN_CORE) << "Cannot enable v-sync as max. swap interval is" << val;
}
} else {
// disable v-sync
eglSwapInterval(eglDisplay(), 0);
}
} else {
/* In the GLX backend, we fall back to using glCopyPixels if we have no extension providing support for partial screen updates.
* However, that does not work in EGL - glCopyPixels with glDrawBuffer(GL_FRONT); does nothing.
* Hence we need EGL to preserve the backbuffer for us, so that we can draw the partial updates on it and call
* eglSwapBuffers() for each frame. eglSwapBuffers() then does the copy (no page flip possible in this mode),
* which means it is slow and not synced to the v-blank. */
qCWarning(KWIN_CORE) << "eglPostSubBufferNV not supported, have to enable buffer preservation - which breaks v-sync and performance";
eglSurfaceAttrib(eglDisplay(), surface(), EGL_SWAP_BEHAVIOR, EGL_BUFFER_PRESERVED);
}
initWayland();
}
bool EglOnXBackend::initRenderingContext()
{
initClientExtensions();
EGLDisplay dpy;
// Use eglGetPlatformDisplayEXT() to get the display pointer
// if the implementation supports it.
const bool havePlatformBase = hasClientExtension(QByteArrayLiteral("EGL_EXT_platform_base"));
setHavePlatformBase(havePlatformBase);
if (havePlatformBase) {
// Make sure that the X11 platform is supported
if (!hasClientExtension(QByteArrayLiteral("EGL_EXT_platform_x11")))
return false;
const int attribs[] = {
EGL_PLATFORM_X11_SCREEN_EXT, m_x11ScreenNumber,
EGL_NONE
};
dpy = eglGetPlatformDisplayEXT(EGL_PLATFORM_X11_EXT, m_x11Display, attribs);
} else {
dpy = eglGetDisplay(m_x11Display);
}
if (dpy == EGL_NO_DISPLAY)
return false;
setEglDisplay(dpy);
initEglAPI();
initBufferConfigs();
if (m_usesOverlayWindow) {
if (!overlayWindow()->create()) {
qCCritical(KWIN_CORE) << "Could not get overlay window";
return false;
} else {
overlayWindow()->setup(None);
}
}
if (!createSurfaces()) {
qCCritical(KWIN_CORE) << "Creating egl surface failed";
return false;
}
if (!createContext()) {
qCCritical(KWIN_CORE) << "Create OpenGL context failed";
return false;
}
if (!makeContextCurrent(surface())) {
qCCritical(KWIN_CORE) << "Make Context Current failed";
return false;
}
EGLint error = eglGetError();
if (error != EGL_SUCCESS) {
qCWarning(KWIN_CORE) << "Error occurred while creating context " << error;
return false;
}
return true;
}
bool EglOnXBackend::createSurfaces()
{
xcb_window_t window = XCB_WINDOW_NONE;
if (m_overlayWindow) {
window = m_overlayWindow->window();
} else if (m_renderingWindow) {
window = m_renderingWindow;
}
EGLSurface surface = createSurface(window);
if (surface == EGL_NO_SURFACE) {
return false;
}
setSurface(surface);
return true;
}
EGLSurface EglOnXBackend::createSurface(xcb_window_t window)
{
if (window == XCB_WINDOW_NONE) {
return EGL_NO_SURFACE;
}
EGLSurface surface = EGL_NO_SURFACE;
if (havePlatformBase()) {
// Note: Window is 64 bits on a 64-bit architecture whereas xcb_window_t is
// always 32 bits. eglCreatePlatformWindowSurfaceEXT() expects the
// native_window parameter to be pointer to a Window, so this variable
// cannot be an xcb_window_t.
surface = eglCreatePlatformWindowSurfaceEXT(eglDisplay(), config(), (void *) &window, nullptr);
} else {
surface = eglCreateWindowSurface(eglDisplay(), config(), window, nullptr);
}
return surface;
}
bool EglOnXBackend::initBufferConfigs()
{
const EGLint config_attribs[] = {
EGL_SURFACE_TYPE, EGL_WINDOW_BIT | (supportsBufferAge() ? 0 : EGL_SWAP_BEHAVIOR_PRESERVED_BIT),
EGL_RED_SIZE, 1,
EGL_GREEN_SIZE, 1,
EGL_BLUE_SIZE, 1,
EGL_ALPHA_SIZE, 0,
EGL_RENDERABLE_TYPE, isOpenGLES() ? EGL_OPENGL_ES2_BIT : EGL_OPENGL_BIT,
EGL_CONFIG_CAVEAT, EGL_NONE,
EGL_NONE,
};
EGLint count;
EGLConfig configs[1024];
if (eglChooseConfig(eglDisplay(), config_attribs, configs, 1024, &count) == EGL_FALSE) {
qCCritical(KWIN_CORE) << "choose config failed";
return false;
}
ScopedCPointer<xcb_get_window_attributes_reply_t> attribs(xcb_get_window_attributes_reply(m_connection,
xcb_get_window_attributes_unchecked(m_connection, m_rootWindow),
nullptr));
if (!attribs) {
qCCritical(KWIN_CORE) << "Failed to get window attributes of root window";
return false;
}
setConfig(configs[0]);
for (int i = 0; i < count; i++) {
EGLint val;
if (eglGetConfigAttrib(eglDisplay(), configs[i], EGL_NATIVE_VISUAL_ID, &val) == EGL_FALSE) {
qCCritical(KWIN_CORE) << "egl get config attrib failed";
}
if (uint32_t(val) == attribs->visual) {
setConfig(configs[i]);
break;
}
}
return true;
}
void EglOnXBackend::present()
{
if (lastDamage().isEmpty())
return;
presentSurface(surface(), lastDamage(), screens()->geometry());
setLastDamage(QRegion());
if (!supportsBufferAge()) {
eglWaitGL();
xcb_flush(m_connection);
}
}
void EglOnXBackend::presentSurface(EGLSurface surface, const QRegion &damage, const QRect &screenGeometry)
{
if (damage.isEmpty()) {
return;
}
const bool fullRepaint = supportsBufferAge() || (damage == screenGeometry);
if (fullRepaint || !surfaceHasSubPost) {
if (gs_tripleBufferNeedsDetection) {
eglWaitGL();
m_swapProfiler.begin();
}
// the entire screen changed, or we cannot do partial updates (which implies we enabled surface preservation)
eglSwapBuffers(eglDisplay(), surface);
if (gs_tripleBufferNeedsDetection) {
eglWaitGL();
if (char result = m_swapProfiler.end()) {
gs_tripleBufferUndetected = gs_tripleBufferNeedsDetection = false;
if (result == 'd' && GLPlatform::instance()->driver() == Driver_NVidia) {
// TODO this is a workaround, we should get __GL_YIELD set before libGL checks it
if (qstrcmp(qgetenv("__GL_YIELD"), "USLEEP")) {
options->setGlPreferBufferSwap(0);
eglSwapInterval(eglDisplay(), 0);
result = 0; // hint proper behavior
qCWarning(KWIN_CORE) << "\nIt seems you are using the nvidia driver without triple buffering\n"
"You must export __GL_YIELD=\"USLEEP\" to prevent large CPU overhead on synced swaps\n"
"Preferably, enable the TripleBuffer Option in the xorg.conf Device\n"
"For this reason, the tearing prevention has been disabled.\n"
"See https://bugs.kde.org/show_bug.cgi?id=322060\n";
}
}
setBlocksForRetrace(result == 'd');
}
}
if (supportsBufferAge()) {
eglQuerySurface(eglDisplay(), surface, EGL_BUFFER_AGE_EXT, &m_bufferAge);
}
} else {
// a part of the screen changed, and we can use eglPostSubBufferNV to copy the updated area
foreach (const QRect & r, damage.rects()) {
eglPostSubBufferNV(eglDisplay(), surface, r.left(), screenGeometry.height() - r.bottom() - 1, r.width(), r.height());
}
}
}
void EglOnXBackend::screenGeometryChanged(const QSize &size)
{
Q_UNUSED(size)
// TODO: base implementation in OpenGLBackend
// The back buffer contents are now undefined
m_bufferAge = 0;
}
SceneOpenGL::TexturePrivate *EglOnXBackend::createBackendTexture(SceneOpenGL::Texture *texture)
{
return new EglTexture(texture, this);
}
QRegion EglOnXBackend::prepareRenderingFrame()
{
QRegion repaint;
if (gs_tripleBufferNeedsDetection) {
// the composite timer floors the repaint frequency. This can pollute our triple buffering
// detection because the glXSwapBuffers call for the new frame has to wait until the pending
// one scanned out.
// So we compensate for that by waiting an extra milisecond to give the driver the chance to
// fllush the buffer queue
usleep(1000);
}
present();
if (supportsBufferAge())
repaint = accumulatedDamageHistory(m_bufferAge);
startRenderTimer();
eglWaitNative(EGL_CORE_NATIVE_ENGINE);
return repaint;
}
void EglOnXBackend::endRenderingFrame(const QRegion &renderedRegion, const QRegion &damagedRegion)
{
if (damagedRegion.isEmpty()) {
setLastDamage(QRegion());
// If the damaged region of a window is fully occluded, the only
// rendering done, if any, will have been to repair a reused back
// buffer, making it identical to the front buffer.
//
// In this case we won't post the back buffer. Instead we'll just
// set the buffer age to 1, so the repaired regions won't be
// rendered again in the next frame.
if (!renderedRegion.isEmpty())
glFlush();
m_bufferAge = 1;
return;
}
setLastDamage(renderedRegion);
if (!blocksForRetrace()) {
// This also sets lastDamage to empty which prevents the frame from
// being posted again when prepareRenderingFrame() is called.
present();
} else {
// Make sure that the GPU begins processing the command stream
// now and not the next time prepareRenderingFrame() is called.
glFlush();
}
if (m_overlayWindow && overlayWindow()->window()) // show the window only after the first pass,
overlayWindow()->show(); // since that pass may take long
// Save the damaged region to history
if (supportsBufferAge())
addToDamageHistory(damagedRegion);
}
bool EglOnXBackend::usesOverlayWindow() const
{
return m_usesOverlayWindow;
}
OverlayWindow* EglOnXBackend::overlayWindow()
{
return m_overlayWindow;
}
bool EglOnXBackend::makeContextCurrent(const EGLSurface &surface)
{
return eglMakeCurrent(eglDisplay(), surface, surface, context()) == EGL_TRUE;
}
/************************************************
* EglTexture
************************************************/
EglTexture::EglTexture(KWin::SceneOpenGL::Texture *texture, KWin::EglOnXBackend *backend)
: AbstractEglTexture(texture, backend)
{
}
EglTexture::~EglTexture() = default;
void KWin::EglTexture::onDamage()
{
if (options->isGlStrictBinding()) {
// This is just implemented to be consistent with
// the example in mesa/demos/src/egl/opengles1/texture_from_pixmap.c
eglWaitNative(EGL_CORE_NATIVE_ENGINE);
glEGLImageTargetTexture2DOES(GL_TEXTURE_2D, (GLeglImageOES) image());
}
GLTexturePrivate::onDamage();
}
} // namespace