screencasting: implement wayland output streaming for egl and wayland backends

plugins/platforms/drm/egl_gbm_backend.cpp

@@ -30,6 +30,7 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #include <kwinglplatform.h>
 // Qt
 #include <QOpenGLContext>
+#include <kwineglimagetexture.h>
 // system
 #include <gbm.h>
 
@@ -251,6 +252,7 @@ void EglGbmBackend::removeOutput(DrmOutput *drmOutput)
     if (it == m_outputs.end()) {
         return;
     }
+
     cleanupOutput(*it);
     m_outputs.erase(it);
 }
@@ -438,17 +440,12 @@ void EglGbmBackend::present()
     // Not in use. This backend does per-screen rendering.
 }
 
-void EglGbmBackend::presentOnOutput(Output &output)
+void EglGbmBackend::presentOnOutput(Output &output, const QRegion &damagedRegion)
 {
     eglSwapBuffers(eglDisplay(), output.eglSurface);
     output.buffer = m_backend->createBuffer(output.gbmSurface);
 
-    if(m_remoteaccessManager && gbm_surface_has_free_buffers(output.gbmSurface->surface())) {
-        // GBM surface is released on page flip so
-        // we should pass the buffer before it's presented.
-        m_remoteaccessManager->passBuffer(output.output, output.buffer);
-    }
-
+    Q_EMIT output.output->outputChange(damagedRegion);
     m_backend->present(output.buffer, output.output);
 
     if (supportsBufferAge()) {
@@ -537,7 +534,7 @@ void EglGbmBackend::endRenderingFrameForScreen(int screenId,
         }
         return;
     }
-    presentOnOutput(output);
+    presentOnOutput(output, damagedRegion);
 
     // Save the damaged region to history
     // Note: damage history is only collected for the first screen. For any other screen full
@@ -565,6 +562,33 @@ bool EglGbmBackend::perScreenRendering() const
     return true;
 }
 
+QSharedPointer<GLTexture> EglGbmBackend::textureForOutput(AbstractOutput *abstractOutput) const
+{
+    const QVector<KWin::EglGbmBackend::Output>::const_iterator itOutput = std::find_if(m_outputs.begin(), m_outputs.end(),
+        [abstractOutput] (const auto &output) {
+            return output.output == abstractOutput;
+        }
+    );
+    if (itOutput == m_outputs.end()) {
+        return {};
+    }
+
+    DrmOutput *drmOutput = itOutput->output;
+    if (!drmOutput->hardwareTransforms()) {
+        const auto glTexture = QSharedPointer<KWin::GLTexture>::create(itOutput->render.texture, GL_RGBA8, drmOutput->pixelSize());
+        glTexture->setYInverted(true);
+        return glTexture;
+    }
+
+    EGLImageKHR image = eglCreateImageKHR(eglDisplay(), nullptr, EGL_NATIVE_PIXMAP_KHR, itOutput->buffer->getBo(), nullptr);
+    if (image == EGL_NO_IMAGE_KHR) {
+        qCWarning(KWIN_DRM) << "Failed to record frame: Error creating EGLImageKHR - " << glGetError();
+        return {};
+    }
+
+    return QSharedPointer<EGLImageTexture>::create(eglDisplay(), image, GL_RGBA8, drmOutput->modeSize());
+}
+
 /************************************************
  * EglTexture
  ************************************************/

plugins/platforms/drm/egl_gbm_backend.h

@@ -28,8 +28,10 @@ struct gbm_surface;
 
 namespace KWin
 {
+class AbstractOutput;
 class DrmBackend;
 class DrmBuffer;
+class DrmSurfaceBuffer;
 class DrmOutput;
 class GbmSurface;
 
@@ -52,6 +54,8 @@ public:
     QRegion prepareRenderingForScreen(int screenId) override;
     void init() override;
 
+    QSharedPointer<GLTexture> textureForOutput(AbstractOutput *requestedOutput) const override;
+
 protected:
     void present() override;
     void cleanupSurfaces() override;
@@ -63,7 +67,7 @@ private:
     void initRemotePresent();
     struct Output {
         DrmOutput *output = nullptr;
-        DrmBuffer *buffer = nullptr;
+        DrmSurfaceBuffer *buffer = nullptr;
         std::shared_ptr<GbmSurface> gbmSurface;
         EGLSurface eglSurface = EGL_NO_SURFACE;
         int bufferAge = 0;
@@ -93,7 +97,7 @@ private:
     void prepareRenderFramebuffer(const Output &output) const;
     void renderFramebufferToSurface(Output &output);
 
-    void presentOnOutput(Output &output);
+    void presentOnOutput(Output &output, const QRegion &damagedRegion);
 
     void removeOutput(DrmOutput *drmOutput);
     void cleanupOutput(Output &output);

plugins/platforms/wayland/egl_wayland_backend.cpp

@@ -32,6 +32,9 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #include "wayland_server.h"
 #include "screens.h"
 
+#include <unistd.h>
+#include <fcntl.h>
+
 // kwin libs
 #include <kwinglplatform.h>
 
@@ -41,6 +44,7 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #include <KWaylandServer/display.h>
 
 // Qt
+#include <QFile>
 #include <QOpenGLContext>
 
 namespace KWin
@@ -288,11 +292,11 @@ void EglWaylandBackend::present()
 {
     for (auto *output: qAsConst(m_outputs)) {
         makeContextCurrent(output);
-        presentOnSurface(output);
+        presentOnSurface(output, output->m_waylandOutput->geometry());
     }
 }
 
-void EglWaylandBackend::presentOnSurface(EglWaylandOutput *output)
+void EglWaylandBackend::presentOnSurface(EglWaylandOutput *output, const QRegion &damage)
 {
     output->m_waylandOutput->surface()->setupFrameCallback();
     if (!m_swapping) {
@@ -300,6 +304,8 @@ void EglWaylandBackend::presentOnSurface(EglWaylandOutput *output)
         Compositor::self()->aboutToSwapBuffers();
     }
 
+    Q_EMIT output->m_waylandOutput->outputChange(damage);
+
     if (supportsBufferAge()) {
         eglSwapBuffers(eglDisplay(), output->m_eglSurface);
         eglQuerySurface(eglDisplay(), output->m_eglSurface, EGL_BUFFER_AGE_EXT, &output->m_bufferAge);
@@ -363,7 +369,8 @@ void EglWaylandBackend::endRenderingFrame(const QRegion &renderedRegion, const Q
 void EglWaylandBackend::endRenderingFrameForScreen(int screenId, const QRegion &renderedRegion, const QRegion &damagedRegion)
 {
     EglWaylandOutput *output = m_outputs[screenId];
-    if (damagedRegion.intersected(output->m_waylandOutput->geometry()).isEmpty() && screenId == 0) {
+    QRegion damage = damagedRegion.intersected(output->m_waylandOutput->geometry());
+    if (damage.isEmpty() && screenId == 0) {
 
         // If the damaged region of a window is fully occluded, the only
         // rendering done, if any, will have been to repair a reused back
@@ -381,7 +388,7 @@ void EglWaylandBackend::endRenderingFrameForScreen(int screenId, const QRegion &
         }
         return;
     }
-    presentOnSurface(output);
+    presentOnSurface(output, damage);
 
     // Save the damaged region to history
     // Note: damage history is only collected for the first screen. See EglGbmBackend
@@ -391,7 +398,7 @@ void EglWaylandBackend::endRenderingFrameForScreen(int screenId, const QRegion &
             output->m_damageHistory.removeLast();
         }
 
-        output->m_damageHistory.prepend(damagedRegion.intersected(output->m_waylandOutput->geometry()));
+        output->m_damageHistory.prepend(damage);
     }
 }
 

plugins/platforms/wayland/egl_wayland_backend.h

@@ -105,7 +105,7 @@ private:
 
     bool makeContextCurrent(EglWaylandOutput *output);
     void present() override;
-    void presentOnSurface(EglWaylandOutput *output);
+    void presentOnSurface(EglWaylandOutput *output, const QRegion &damagedRegion);
 
     WaylandBackend *m_backend;
     QVector<EglWaylandOutput*> m_outputs;

plugins/platforms/wayland/wayland_backend.cpp

@@ -460,13 +460,13 @@ WaylandBackend::WaylandBackend(QObject *parent)
 
 
     char const *drm_render_node = "/dev/dri/renderD128";
-    m_drm_fd = open(drm_render_node, O_RDWR);
-    if (m_drm_fd < 0) {
+    m_drmFileDescriptor = open(drm_render_node, O_RDWR);
+    if (m_drmFileDescriptor < 0) {
         qCWarning(KWIN_WAYLAND_BACKEND) << "Failed to open drm render node" << drm_render_node;
         m_gbmDevice = nullptr;
         return;
     }
-    m_gbmDevice = gbm_create_device(m_drm_fd);
+    m_gbmDevice = gbm_create_device(m_drmFileDescriptor);
 }
 
 WaylandBackend::~WaylandBackend()
@@ -492,7 +492,7 @@ WaylandBackend::~WaylandBackend()
     m_connectionThread->wait();
     m_connectionThreadObject->deleteLater();
     gbm_device_destroy(m_gbmDevice);
-    close(m_drm_fd);
+    close(m_drmFileDescriptor);
 
     qCDebug(KWIN_WAYLAND_BACKEND) << "Destroyed Wayland display";
 }