Chase Douglas wrote: > I've been toiling with mesa a bit and have what I believe to be the > beginning of support for large resolution 3D. At this point it is very > hacked together just so I can prove that it's possible. The theory of > operation is to create an extra framebuffer and batchbuffer when a > context is initialized. Everything that is sent to the first batchbuffer > is also sent to the second batchbuffer, excepting that color and depth > buffer addrs and scissor boxes are modified for the extra batchbuffer. > At this point, I haven't looked too deep into when I need to call > Viewport to change between the two framebuffer renders, but I will get > to that later. In the copybuffers routine, I blit both buffers to the > screen. > > First, I want to know what others think of the theory. I have attached > my patch to the i915tex_privbuffers branch driver below. If there are > any architectural issues with my approach I would surely be interested > to here them and how they might be addressed. > Theory is mostly good however i see a couple of issues. First the big one is that you put to much things in the driver, in fact this limitation would be better worked out in core mesa without having to touch the driver. Mainly because every driver otherwise will have to duplicate the code and i believe this somethings that should be avoided. Moreover i think it will be easier and cleaner to hack this into mesa because mesa have a better view of what is going on, i will balance this a bit as there is still need for some card information more below.
Now, here is the tricky part, card have CRTC limits so you will either have to work around those too or just accept them (for "older" card this limit is greater than 3d limit so you might be happy with them). Other big problem is when cutting a big frame buffer and render too it, you will have to ask the driver to tell you where and how to split the big frame buffer in smaller chunk (and i think this should be the only driver specific thing) and that might even be not possible (i would have to hack a bit on some card to test this) in some case: for instance if you got a tiled frame buffer, i am not sure you can render properly to several small part of a big buffer using tiles as there might be side effect at borders of small buffers as i believe 3d render buffer have some memory alignment (needing stride). And if you render big frame buffer i am sure you do not want to loose tiles speed boost. Cheers, Jerome Glisse ------------------------------------------------------------------------- This SF.net email is sponsored by: Splunk Inc. Still grepping through log files to find problems? Stop. Now Search log events and configuration files using AJAX and a browser. Download your FREE copy of Splunk now >> http://get.splunk.com/ _______________________________________________ Mesa3d-dev mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/mesa3d-dev
