[D3D] Some execute buffers rewrites + misc fixes

[Lionel Ulmer]

> This seems like the Copy/Paste syndrom [:-)]

Anyway, I fixed it in one of my pending patch.

> Yes! From a ZBuffer surface to another... Don't remember the game 
> though... (because it crashed in another part of wine)

Wow... This is nice :-)

> When doing the standard blit, the app set the DDBLT struct pointer to 
> NULL so
> without the check this simply crashes when accessing the depthfill 
> member of the structure.

Yeah, it's in my plans to have the ZBuffer a bit better handled to not crash
when applications do strange things with it...

Proper Lock / Blt support will never be fast on any GL implementation I know
though :-/

> Yes this can be done as well. [:-)]

Fixed it in one of my patches too.

> Because the world transformation introduced the W coordinate which 
> cannot be passed
> to drawing functions. But well, this coordinate should be always be 1 
> after the world transformation so we can ommit it.

Well, you can pass the W coordinates using the 1/W trick, no ? If you use
the XYZRHW format and give it X, Y, Z, 1/W after your computation it should
work, no ? Slow but working from what I can see...

> Oh! Well I forgot this hack... [;-)]

I think to support this using GL, we should use the feedback buffer. Will
surely be slow, but well, better than to write our own lighting :-)

       Lionel

-- 
		 Lionel Ulmer - http://www.bbrox.org/