Add and use QGLContextPrivate::eglSurfaceForDevice()

The QGLContext only stores the EGLSurface for QWidgets & QGLWidgets,
other device types like QPixmap & QGLPixelBuffer store the surface
themsselves. With this patch it is possible to create a QGLContext
on a QPixmap, make it current and render GL to that QPixmap on X11.

Reviewed-By: TrustMe

4 files changed, 33 insertions, 4 deletions

diff --git a/src/opengl/qgl_egl.cpp b/src/opengl/qgl_egl.cpp
index f1abab8..7bfcf27 100644
--- a/src/opengl/qgl_egl.cpp
+++ b/src/opengl/qgl_egl.cpp
@@ -40,8 +40,14 @@
 ****************************************************************************/
 
 #include <QtOpenGL/qgl.h>
+#include <QtOpenGL/qglpixelbuffer.h>
 #include "qgl_p.h"
 #include "qgl_egl_p.h"
+#include "qglpixelbuffer_p.h"
+
+#ifdef Q_WS_X11
+#include <QtGui/private/qpixmap_x11_p.h>
+#endif
 
 QT_BEGIN_NAMESPACE
 
@@ -154,12 +160,12 @@ void QGLContext::reset()
 void QGLContext::makeCurrent()
 {
     Q_D(QGLContext);
-    if (!d->valid || !d->eglContext || d->eglSurface == EGL_NO_SURFACE) {
+    if (!d->valid || !d->eglContext || d->eglSurfaceForDevice() == EGL_NO_SURFACE) {
         qWarning("QGLContext::makeCurrent(): Cannot make invalid context current");
         return;
     }
 
-    if (d->eglContext->makeCurrent(d->eglSurface))
+    if (d->eglContext->makeCurrent(d->eglSurfaceForDevice()))
         QGLContextPrivate::setCurrentContext(this);
 }
 
@@ -179,7 +185,7 @@ void QGLContext::swapBuffers() const
     if (!d->valid || !d->eglContext)
         return;
 
-    d->eglContext->swapBuffers(d->eglSurface);
+    d->eglContext->swapBuffers(d->eglSurfaceForDevice());
 }
 
 void QGLContextPrivate::destroyEglSurfaceForDevice()
@@ -202,6 +208,27 @@ void QGLContextPrivate::destroyEglSurfaceForDevice()
     }
 }
 
+EGLSurface QGLContextPrivate::eglSurfaceForDevice() const
+{
+    if (paintDevice->devType() == QInternal::Widget)
+        return eglSurface;
+    if (paintDevice->devType() == QInternal::Pixmap) {
+#ifdef Q_WS_X11
+        QPixmapData *pmd = static_cast<QPixmap*>(paintDevice)->data_ptr().data();
+        if (pmd->classId() == QPixmapData::X11Class) {
+            QX11PixmapData* x11PixmapData = static_cast<QX11PixmapData*>(pmd);
+            return (EGLSurface)x11PixmapData->gl_surface;
+        } else
+#endif
+            return eglSurface;
+    }
+    if (paintDevice->devType() == QInternal::Pbuffer) {
+        QGLPixelBuffer* pbuf = static_cast<QGLPixelBuffer*>(paintDevice);
+        return pbuf->d_func()->pbuf;
+    }
+    return EGL_NO_SURFACE;
+}
+
 void QGLWidget::setMouseTracking(bool enable)
 {
     QWidget::setMouseTracking(enable);
diff --git a/src/opengl/qgl_p.h b/src/opengl/qgl_p.h
index ecd8b43..b828bea 100644
--- a/src/opengl/qgl_p.h
+++ b/src/opengl/qgl_p.h
@@ -356,6 +356,7 @@ public:
     QEglContext *eglContext;
     EGLSurface eglSurface;
     void destroyEglSurfaceForDevice();
+    EGLSurface eglSurfaceForDevice() const;
 #elif defined(Q_WS_X11) || defined(Q_WS_MAC)
     void* cx;
 #endif
diff --git a/src/opengl/qgl_x11egl.cpp b/src/opengl/qgl_x11egl.cpp
index bcde8c4..ba05e72 100644
--- a/src/opengl/qgl_x11egl.cpp
+++ b/src/opengl/qgl_x11egl.cpp
@@ -229,7 +229,7 @@ bool QGLContext::chooseContext(const QGLContext* shareContext)
     //    QWidget - yes, create the EGLSurface and store it in QGLContextPrivate::eglSurface
     //    QGLWidget - yes, create the EGLSurface and store it in QGLContextPrivate::eglSurface
     //    QPixmap - yes, create the EGLSurface but store it in QX11PixmapData::gl_surface
-    //    QGLPixelBuffer - no, it creates the surface itself
+    //    QGLPixelBuffer - no, it creates the surface itself and stores it in QGLPixelBufferPrivate::pbuf
 
     if (devType == QInternal::Widget) {
         if (d->eglSurface != EGL_NO_SURFACE)
diff --git a/src/opengl/qglpixelbuffer.h b/src/opengl/qglpixelbuffer.h
index 3304dd8..d9c7e3e 100644
--- a/src/opengl/qglpixelbuffer.h
+++ b/src/opengl/qglpixelbuffer.h
@@ -112,6 +112,7 @@ private:
     friend class QGLWindowSurface;
     friend class QGLPaintDevice;
     friend class QGLPBufferGLPaintDevice;
+    friend class QGLContextPrivate;
 };
 
 QT_END_NAMESPACE