[sldev] Re: possible rendering improvement

[John Hurliman]

Argent Stonecutter wrote:
>> Without looking at the code, it is probably a question about what's more
>> expensive: Checking _every_ surface's alpha-setting or rendering
>> invisible surfaces. (Maybe we should take a walk through the grid with a
>> modified client that counts surfaces...)
>
> The client has to check every surface's alpha setting *anyway* to tell 
> the GPU what it is, so simply not sending the surface to the GPU at 
> all if the Alpha is 0 should be almost free.
>
> Checking the texture for ones that are completely transparent may be a 
> little more difficult, but again it has to process the texture before 
> uploading it to the GPU, and having the client keep track of the 
> textures that have no non-zero pixels in the alpha mask wouldn't take 
> much storage, one extra bit per texture...
>
The picking code requires that even invisible objects exist in 3D space.

John