Added explicit threading API to QtOpenGL.

Since QtOpenGL/QGLContext is implemented in terms of
QtGui/QOpenGLContext which has stricter requirements about how it's
supposed to be used, we need to apply these requirements to QGLContext
as well.

This change adds QGLContext::moveToThread(QThread *) and documents it as
a necessity for making a context current on another thread.

Also introduces QGLPixelbuffer::context() to access the QGLContext of a
pixelbuffer, and made QGLWidget::context() return a non-const
QGLContext, since there's no good reason why it shouldn't, and it leads
to less const_cast clutter.

We could have introduced a backdoor in QOpenGLContext instead, making it
loosen its requirements, but that would have made it harder / impossible
to fully support threaded OpenGL in all the platforms.

Task-number: QTBUG-22560
Change-Id: Ibb6f65f342e7c963e80cc42ab5664c5f1cab30b0
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@digia.com>
Reviewed-by: Gunnar Sletta <gunnar.sletta@digia.com>

1 files changed, 2 insertions, 0 deletions

diff --git a/src/opengl/qglpixelbuffer_p.h b/src/opengl/qglpixelbuffer_p.h
index fd20cee07a..caa2e2f7d1 100644
--- a/src/opengl/qglpixelbuffer_p.h
+++ b/src/opengl/qglpixelbuffer_p.h
@@ -68,8 +68,10 @@ public:
     virtual QPaintEngine* paintEngine() const {return pbuf->paintEngine();}
     virtual QSize size() const {return pbuf->size();}
     virtual QGLContext* context() const;
+    virtual void beginPaint();
     virtual void endPaint();
     void setPBuffer(QGLPixelBuffer* pb);
+    void setFbo(GLuint fbo);
 private:
     QGLPixelBuffer* pbuf;
 };