implement window surface

[Brian Paul]

David Reveman wrote:
> On Tue, 2005-05-17 at 15:44 -0600, Brian Paul wrote: 
> 
>>Jon Smirl wrote:
>>
>>>Don't I need to implement window surfaces in the fbdev EGL driver? In
>>>other words the ability to create a surface that will draw to a
>>>clipped rectangle on an existing screen surface.  Without clipped
>>>surfaces how can you implement a non-composed Xserver?
>>
>>The eglCreateWindowSurface() function is designed to be used in 
>>conjunction with the native window system's windows (X window or Win32 
>>window, etc).  It takes a <NativeWindowType> parameter.  So you'd use 
>>the native window system API to manage the window (XMoveWindow, 
>>XResizeWindow, XMapWindow, etc).
>>
>>So in our X-less EGL environment we'd probably need to add all those 
>>sorts of functions.
>>
>>Another option I've been considering is to develop a new OpenGL/Mesa 
>>extension that extends the glScissor feature to allow clipping against 
>>a list of rectangles, not just one.  This would be used to implement 
>>cliprects for window regions.  The DRI drivers already support this 
>>internally for window clipping so it shouldn't be too hard to implement.
>>
>>What do the XGL people think of that?
> 
> 
> That would be nice. There's a clip rects interface in glitz that is
> currently implemented using glScissor and multiple drawing operations.
> It'd be very easy to have this utilize an extension like this when
> available. 

OK, if you think it would be worthwhile, I'll try to sketch out the 
spec for it.

-Brian