From cc5ae2db39bd5cb5e7710b1b7ce1b5c92b705450 Mon Sep 17 00:00:00 2001 From: Rhys Weatherley Date: Thu, 17 Dec 2009 14:54:05 +1000 Subject: Update FBO docs to describe how QPainter changes the GL state Using a QPainter on a QGLFramebufferObject will not return the GL context to its original conditions, especially with the OpenGL2 paint engine. Update the docs to make this clearer. Task-number: QTBUG-6712 Reviewed-by: Daniel Pope --- src/opengl/qglframebufferobject.cpp | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/src/opengl/qglframebufferobject.cpp b/src/opengl/qglframebufferobject.cpp index d0297c9..4b5c30a 100644 --- a/src/opengl/qglframebufferobject.cpp +++ b/src/opengl/qglframebufferobject.cpp @@ -597,6 +597,12 @@ void QGLFramebufferObjectPrivate::init(QGLFramebufferObject *q, const QSize &sz, the constructors that take a QGLFramebufferObject parameter, and set the QGLFramebufferObject::samples() property to a non-zero value. + When painting to a QGLFramebufferObject using QPainter, the state of + the current GL context will be altered by the paint engine to reflect + its needs. Applications should not rely upon the GL state being reset + to its original conditions, particularly the current shader program, + GL viewport, texture units, and drawing modes. + For multisample framebuffer objects a color render buffer is created, otherwise a texture with the specified texture target is created. The color render buffer or texture will have the specified internal -- cgit v0.12