Update QGLFormat from EGLConfig properly

Previously, some members of QGLFormat (like alphaBufferSize) would
be left to the initial -1 value.

Reviewed-By: TrustMe

6 files changed, 38 insertions, 45 deletions

diff --git a/src/opengl/qgl_egl.cpp b/src/opengl/qgl_egl.cpp
index 3d146b7..c08d6fd 100644
--- a/src/opengl/qgl_egl.cpp
+++ b/src/opengl/qgl_egl.cpp
@@ -111,46 +111,40 @@ void qt_eglproperties_set_glformat(QEglProperties& eglProperties, const QGLForma
     eglProperties.setValue(EGL_SAMPLE_BUFFERS, sampleCount ? 1 : 0);
 }
 
-
 // Updates "format" with the parameters of the selected configuration.
-void qt_egl_update_format(const QEglContext& context, QGLFormat& format)
+void qt_glformat_from_eglconfig(QGLFormat& format, const EGLConfig config)
 {
-    EGLint value = 0;
-
-    if (context.configAttrib(EGL_RED_SIZE, &value))
-        format.setRedBufferSize(value);
-    if (context.configAttrib(EGL_GREEN_SIZE, &value))
-        format.setGreenBufferSize(value);
-    if (context.configAttrib(EGL_BLUE_SIZE, &value))
-        format.setBlueBufferSize(value);
-    if (context.configAttrib(EGL_ALPHA_SIZE, &value)) {
-        format.setAlpha(value != 0);
-        if (format.alpha())
-            format.setAlphaBufferSize(value);
-    }
-
-    if (context.configAttrib(EGL_DEPTH_SIZE, &value)) {
-        format.setDepth(value != 0);
-        if (format.depth())
-            format.setDepthBufferSize(value);
-    }
-
-    if (context.configAttrib(EGL_LEVEL, &value))
-        format.setPlane(value);
-
-    if (context.configAttrib(EGL_SAMPLE_BUFFERS, &value)) {
-        format.setSampleBuffers(value != 0);
-        if (format.sampleBuffers()) {
-            context.configAttrib(EGL_SAMPLES, &value);
-            format.setSamples(value);
-        }
-    }
-
-    if (context.configAttrib(EGL_STENCIL_SIZE, &value)) {
-        format.setStencil(value != 0);
-        if (format.stencil())
-            format.setStencilBufferSize(value);
-    }
+    EGLint redSize     = 0;
+    EGLint greenSize   = 0;
+    EGLint blueSize    = 0;
+    EGLint alphaSize   = 0;
+    EGLint depthSize   = 0;
+    EGLint stencilSize = 0;
+    EGLint sampleCount = 0;
+    EGLint level       = 0;
+
+    EGLDisplay display = QEgl::display();
+    eglGetConfigAttrib(display, config, EGL_RED_SIZE,     &redSize);
+    eglGetConfigAttrib(display, config, EGL_GREEN_SIZE,   &greenSize);
+    eglGetConfigAttrib(display, config, EGL_BLUE_SIZE,    &blueSize);
+    eglGetConfigAttrib(display, config, EGL_ALPHA_SIZE,   &alphaSize);
+    eglGetConfigAttrib(display, config, EGL_DEPTH_SIZE,   &depthSize);
+    eglGetConfigAttrib(display, config, EGL_STENCIL_SIZE, &stencilSize);
+    eglGetConfigAttrib(display, config, EGL_SAMPLES,      &sampleCount);
+    eglGetConfigAttrib(display, config, EGL_LEVEL,        &level);
+
+    format.setRedBufferSize(redSize);
+    format.setGreenBufferSize(greenSize);
+    format.setBlueBufferSize(blueSize);
+    format.setAlphaBufferSize(alphaSize);
+    format.setDepthBufferSize(depthSize);
+    format.setStencilBufferSize(stencilSize);
+    format.setSamples(sampleCount);
+    format.setPlane(level + 1);      // EGL calls level 0 "normal" whereas Qt calls 1 "normal"
+    format.setDirectRendering(true); // All EGL contexts are direct-rendered
+    format.setRgba(true);            // EGL doesn't support colour index rendering
+    format.setStereo(false);         // EGL doesn't support stereo buffers
+    format.setAccumBufferSize(0);    // EGL doesn't support accululation buffers
 
     // Clear the EGL error state because some of the above may
     // have errored out because the attribute is not applicable
diff --git a/src/opengl/qgl_egl_p.h b/src/opengl/qgl_egl_p.h
index 6b65227..43793cd 100644
--- a/src/opengl/qgl_egl_p.h
+++ b/src/opengl/qgl_egl_p.h
@@ -61,7 +61,7 @@ QT_BEGIN_NAMESPACE
 class QGLFormat;
 
 void qt_eglproperties_set_glformat(QEglProperties& props, const QGLFormat& format);
-void qt_egl_update_format(const QEglContext& context, QGLFormat& format);
+void qt_glformat_from_eglconfig(QGLFormat& format, const EGLConfig config);
 
 QT_END_NAMESPACE
 
diff --git a/src/opengl/qgl_qws.cpp b/src/opengl/qgl_qws.cpp
index f72f051..96b2454 100644
--- a/src/opengl/qgl_qws.cpp
+++ b/src/opengl/qgl_qws.cpp
@@ -200,7 +200,7 @@ bool QGLContext::chooseContext(const QGLContext* shareContext)
     }
 
     // Inform the higher layers about the actual format properties.
-    qt_egl_update_format(*(d->eglContext), d->glFormat);
+    qt_glformat_from_eglconfig(d->glFormat, d->eglContext->config());
 
     // Create a new context for the configuration.
     if (!d->eglContext->createContext
diff --git a/src/opengl/qgl_wince.cpp b/src/opengl/qgl_wince.cpp
index 3bf7f3a..fefcca2 100644
--- a/src/opengl/qgl_wince.cpp
+++ b/src/opengl/qgl_wince.cpp
@@ -163,7 +163,7 @@ bool QGLContext::chooseContext(const QGLContext* shareContext)
     }
 
     // Inform the higher layers about the actual format properties.
-    qt_egl_update_format(*(d->eglContext), d->glFormat);
+    qt_glformat_from_eglconfig(d->glFormat, d->eglContext->config());
 
     // Create a new context for the configuration.
     if (!d->eglContext->createContext
diff --git a/src/opengl/qgl_x11egl.cpp b/src/opengl/qgl_x11egl.cpp
index a7c92cf..fe87c65 100644
--- a/src/opengl/qgl_x11egl.cpp
+++ b/src/opengl/qgl_x11egl.cpp
@@ -216,9 +216,8 @@ bool QGLContext::chooseContext(const QGLContext* shareContext)
             const_cast<QGLContext *>(shareContext)->d_func()->sharing = true;
     }
 
-    // Inform the higher layers about the actual format properties.
-    qt_egl_update_format(*(d->eglContext), d->glFormat);
-
+    // Inform the higher layers about the actual format properties
+    qt_glformat_from_eglconfig(d->glFormat, d->eglContext->config());
 
     // Do don't create the EGLSurface for everything.
     //    QWidget - yes, create the EGLSurface and store it in QGLContextPrivate::eglSurface
diff --git a/src/opengl/qglpixelbuffer_egl.cpp b/src/opengl/qglpixelbuffer_egl.cpp
index ee0714f..db9e754 100644
--- a/src/opengl/qglpixelbuffer_egl.cpp
+++ b/src/opengl/qglpixelbuffer_egl.cpp
@@ -113,7 +113,7 @@ bool QGLPixelBufferPrivate::init(const QSize &size, const QGLFormat &f, QGLWidge
     }
 
     // Retrieve the actual format properties.
-    qt_egl_update_format(*ctx, format);
+    qt_glformat_from_eglconfig(format, ctx->config());
 
     // Create the attributes needed for the pbuffer.
     QEglProperties attribs;