osg::GraphicsContext, in order to give good integration with the
application's GUI toolkit. This works really well.
However, I need to share OpenGL texture resources with the standard
osgViewer GraphicsContext implementations, in particular the
PixelBuffers. This is essential for my application to conserve graphics
memory on low-end hardware. Currently the standard osg implementations
will not share resources with another derived osg::GraphicsContext,
other than the pre-defined osgViewer classes e.g. PixelBufferX11 is
hardcoded to only share resources with GraphicsWindowX11 and
PixelBufferX11 objects, and no other osg::GraphicsContext object.
To address this in the cleanest way I could think of, I have moved the
OpenGL handle variables for each platform into a small utility class,
e.g. GraphicsHandleX11 for unix. Then GraphicsWindowX11, PixelBufferX11
and any other derived osg::GraphicsContext class can inherit from
GraphicsHandleX11 to share OpenGL resources.
I have updated the X11, Win32 and Carbon implementations to use this.
The changes are minor. I haven't touched the Cocoa implmentation as
I'm not familiar with it at all and couldn't test it - it will work
unchanged.
Without this I had some horrible hacks in my application, this greatly
simplifies things for me. It also simplifies the osgViewer
implementations slightly. Perhaps it may help with other users'
desires to share resources with external graphics contexts, as was
discussed on the user list recently."
Notes from Robert Osfield, adapted Colin's submission to work with the new EGL related changes.
carbon-implementation of GraphicsWindow. Now you can use an AGLDrawable
in conjunction with osgViewer/osgCompositeViewer."
Changes from Robert Osfield, changed std::cout to osg::notify(osg::INFO)
Stephan: "attached you'll find some modifications to the GraphicsWindow-class and
their platform-dependant implementations.
The problem:
setWindowRectangle and setWindowDecoration do not update the
traits-object, so, if you call setWindowRectangle on a
not-realized-window it will open with another size when realized later.
getWindowRectangle reports possible wrong sizes if setWindowRectangle
called before.
My solution:
split the implementation in two parts:
GraphicsWindow::setWindowRectangle will update its traits-object and
call afterwards the virtual method setWindowRectangleImplementation
(which is implemented by the derived platformspecific classess). For
setWindowDecoration I am useing a similar mechanism.
I hope you'll find the submission useful, the Win32 and X11 changes are
not tested but should work."
Changes to this made by Robert are call of resized in setWindowRectangle
instead of setting of Traits, and use of a bool return type.
changes I made:
+ put a warning in the console if a nonexistant screen is requested
+ add getters for the aglcontext and pixelformat -- I need access to
them in my own code.
"
implementation of GraphicsWindow:
- usage of WindowData, you can specify an existing window to use via
osg::Traits
- implementation of setScreenResolution and setScreenRefreshRate
- implementation of setWindowDecoration when window is already created.
There seems to be a bug regarding multiple threads and closing windows,
see my other mail on osg-users.
"
