Bitmap mapping size vs. speed

[Markvanhandel]

Hey, a quick search through the forums didn't turn this up so I will ask:

Is there much of a render time difference between texture mapping with more smaller bitmaps tiled or tiling fewer larger bitmaps? This pretty much applies to a repeated pattern texture.

Thanks.

[dalomar_cg]

Re: Bitmap mapping size vs. speed

The short answer is yes, the larger your textures are the slower it will render, but there's more that goes into it than that.

The long answer is as follows... As far as the actual render process V-Ray doesn't care how big the texture is because its got to grab the color info from somewhere, whether its from a large texture or a repeated texture it doesn't make much difference. However large textures will require more memory, and thats where the issue comes in. Memory issues won't really come into play until you start running out (of physical memory that is). Up until that point you probably won't notice any difference in render times, but after all of the physical memory is used up then any thing that needs to be held within memory is handled through virtual memory which is considerably slower. Thats when you notice v-ray dragging its feet. Of course if you throw tons of huge texture in there your going to run the risk of things crashing as well.

[Markvanhandel]

Re: Bitmap mapping size vs. speed

Sounds reasonable.

Thanks very much.