A simple texture question.

silvergazimon

I have been banging my head against the wall over the years trying to find out how is the environment textured? I looked all over for how is it done, I know that many objects and character models are usually mapped by ether a one map or multiple maps (depending on the studio, I know) but never heard a peep on the levels itself.

If it helps here's some examples of what I am aiming for.

The environment is as large as GTA3 map, with hardware close to the playstation1 (I am planning of some MUCH more powerful but I want to make sure it would works on low-to-mid class computers.)

Thanks in advance.

Rick Stirling

It varies, but mostly it's lots of tilable ground textures. In the older days we'd create textures that would blend between different surfaces (grass to dirt etc.), but these days people tend to blend by using mix/blend maps. Different engines/studios do this in different ways - some will paint an alpha blend texture, others will use the vertex alpha channel to control the blending on the geometry itself.

rhoymand

rick beat me to it =P

yeah, I think its mostly 64/128 tiling textures with a combination of vertex coloring and alpha maps for lighting. not really sure what psx supported... only things with non-tiling textures are props, but it really depends on the prop too.

Joshua Stubbles

Depends on the system then, I suppose. Vertex alpha blending is usually done on systems with limited amounts of ram and/or video memory. Or it's used as a way to free up video mem for something else.

Painting a blend map is ultimately best in terms of quality. It's a per-pixel b&w image that says blend on the white pixels. Though this is also far more expensive than vertex blending. You have to balance everything.

danr

there was no texture tiling on the PSX, but that's specific to that hardware, not necessarily low-end tech

Eric Chadwick

Vassago wrote: »

It's a per-pixel b&w image that says blend on the white pixels.

At Whatif ours was just this, black and white. But in the Artificial Studios' Reality Engine you could use all four channels of a RGBA texture, each one controlling one of four tiled bitmaps. Same kind of idea, just more channels. Too bad their wiki is gone now. Ogre uses RGB vertex colors to blend multiple m aps together, kind of similar.

EarthQuake

We use a RBGA image for our terrain masking. The RGB is used as a multiply to get color variation, and the alpha is used to blend between the 4 different maps, each map getting 25% of the values. One of the disadvantages of a system like this is you can only blend in order, you cant blend from say, layer 1 to layer 4. You have to blend from 1, to 2, to 3 and finally to 4.

Eric Chadwick

Hey that's a cool optimization trick.

SHEPEIRO

depends, outdoor scenes as above, but indoor and achitectural scenes can be made from alot of tilable/ non-tilable components.we still use vertice blending between lots of material layers in our ground, speeds up draw apparently but is a pain the ass with mayas love of dropping mulitple coloursets

roll on unique mapping