Re: [Mesa3d-dev] Mesa (master): vbo: Fix array pointer calculation for MapBufferRange-mapped vertex data.

[Brian P. <br...@vm...>]

Eric Anholt wrote:
> On Sat, 2009-08-29 at 11:24 -0700, Jose Fonseca wrote:
>> Eric,
>>
>> This change broke softpipe on master (eg. terrain), and probably all gallium based drivers. I'm pretty sure the vbo module was working correctly without it, so there might be a different in the interpretation of the MapBufferRange semantics between the drivers, but I couldn't find it just by llooking at intel's and mesa state tracker implementation of MapBufferRange.
>>
>> Was there any particular bug this change fixed?
> 
> Yes, garbage was drawn all over the screen when enabling VBOs in the VBO
> module.  obj->Pointer should pretty clearly be the pointer to the mapped
> range, as if you're creating a temporary space (system memory or
> temporary buffer object) as part of MapRange, where else would it point
> -- to an unmapped address?  It also then matches the
> ARB_map_buffer_range semantics.  Looks like a quick fix in
> st_bufferobj_map_range.

I'll check in a fix for this shortly...

-Brian