From 2c36469a16f166a3b4e513cccf8186157952bba0 Mon Sep 17 00:00:00 2001 From: Fabian Bumberger Date: Mon, 17 Mar 2014 17:45:08 +0100 Subject: QNX: Fix OpenGL autotest On QNX grabbing the frame buffer returns the content of the back buffer. In order to execute the OpenGL tests properly a swapBuffers is executed before in order to be able to retrieve the content of the front buffer. The patch also documents this platform behavior. Change-Id: I7a501818ec6eea061f2f54f95854f68cb72e0534 Reviewed-by: James McDonnell Reviewed-by: Sean Harmer --- src/opengl/qgl.cpp | 5 +++++ src/opengl/qglframebufferobject.cpp | 3 +++ tests/auto/opengl/qgl/tst_qgl.cpp | 30 +++++++++++++++++++++++++++++- 3 files changed, 37 insertions(+), 1 deletion(-) diff --git a/src/opengl/qgl.cpp b/src/opengl/qgl.cpp index e602a05af9..637cfc55a8 100644 --- a/src/opengl/qgl.cpp +++ b/src/opengl/qgl.cpp @@ -4083,6 +4083,11 @@ QPixmap QGLWidget::renderPixmap(int w, int h, bool useContext) Depending on your hardware, you can explicitly select which color buffer to grab with a glReadBuffer() call before calling this function. + + On QNX the back buffer is not preserved when swapBuffers() is called. The back buffer + where this function reads from, might thus not contain the same content as the front buffer. + In order to retrieve what is currently visible on the screen, swapBuffers() + has to be executed prior to this function call. */ QImage QGLWidget::grabFrameBuffer(bool withAlpha) { diff --git a/src/opengl/qglframebufferobject.cpp b/src/opengl/qglframebufferobject.cpp index d636da91b5..bd8bc2f64a 100644 --- a/src/opengl/qglframebufferobject.cpp +++ b/src/opengl/qglframebufferobject.cpp @@ -1114,6 +1114,9 @@ QGLFramebufferObjectFormat QGLFramebufferObject::format() const \fn QImage QGLFramebufferObject::toImage() const Returns the contents of this framebuffer object as a QImage. + + On QNX the back buffer is not preserved when a buffer swap occures. So this function + might return old content. */ QImage QGLFramebufferObject::toImage() const { diff --git a/tests/auto/opengl/qgl/tst_qgl.cpp b/tests/auto/opengl/qgl/tst_qgl.cpp index 22f284e365..5831b33974 100644 --- a/tests/auto/opengl/qgl/tst_qgl.cpp +++ b/tests/auto/opengl/qgl/tst_qgl.cpp @@ -1064,6 +1064,12 @@ void tst_QGL::glWidgetRendering() QVERIFY(w.beginOk); QVERIFY(w.engineType == QPaintEngine::OpenGL || w.engineType == QPaintEngine::OpenGL2); +#if defined(Q_OS_QNX) + // glReadPixels reads from the back buffer. On QNX the buffer is not preserved + // after a buffer swap. This is why we have to swap the buffer explicitly before calling + // grabFrameBuffer to retrieve the content of the front buffer. + w.swapBuffers(); +#endif QImage fb = w.grabFrameBuffer(false); qt_opengl_check_test_pattern(fb); } @@ -1104,6 +1110,9 @@ void tst_QGL::glFBOSimpleRendering() // buffer is actually missing. But that's probably ok anyway. void tst_QGL::glFBORendering() { +#if defined(Q_OS_QNX) + QSKIP("Reading the QGLFramebufferObject is unsupported on this platform"); +#endif if (!QGLFramebufferObject::hasOpenGLFramebufferObjects()) QSKIP("QGLFramebufferObject not supported on this platform"); @@ -1280,7 +1289,7 @@ protected: fboPainter.end(); fboImage = fbo->toImage(); - widgetPainter.fillRect(-1, -1, width()+2, width()+2, Qt::blue); + widgetPainter.fillRect(-1, -1, width()+2, height()+2, Qt::blue); delete fbo; } @@ -1301,6 +1310,13 @@ void tst_QGL::glFBOUseInGLWidget() QVERIFY(w.widgetPainterBeginOk); QVERIFY(w.fboPainterBeginOk); +#if defined(Q_OS_QNX) + // glReadPixels reads from the back buffer. On QNX the buffer is not preserved + // after a buffer swap. This is why we have to swap the buffer explicitly before calling + // grabFrameBuffer to retrieve the content of the front buffer + w.swapBuffers(); +#endif + QImage widgetFB = w.grabFrameBuffer(false); QImage widgetReference(widgetFB.size(), widgetFB.format()); widgetReference.fill(0xff0000ff); @@ -1691,6 +1707,12 @@ void tst_QGL::replaceClipping() glw.paint(&referencePainter); referencePainter.end(); +#if defined(Q_OS_QNX) + // glReadPixels reads from the back buffer. On QNX the buffer is not preserved + // after a buffer swap. This is why we have to swap the buffer explicitly before calling + // grabFrameBuffer to retrieve the content of the front buffer + glw.swapBuffers(); +#endif const QImage widgetFB = glw.grabFrameBuffer(false).convertToFormat(QImage::Format_RGB32); // Sample pixels in a grid pattern which avoids false failures due to @@ -1802,6 +1824,12 @@ void tst_QGL::clipTest() glw.paint(&referencePainter); referencePainter.end(); +#if defined(Q_OS_QNX) + // glReadPixels reads from the back buffer. On QNX the buffer is not preserved + // after a buffer swap. This is why we have to swap the buffer explicitly before calling + // grabFrameBuffer to retrieve the content of the front buffer + glw.swapBuffers(); +#endif const QImage widgetFB = glw.grabFrameBuffer(false).convertToFormat(QImage::Format_RGB32); // Sample pixels in a grid pattern which avoids false failures due to -- cgit v1.2.3