Topic: idtech texture sizes

[ratty redemption]

hi guys,

i've been working on a cliff face that is intended for use in the xreal engine, which iirc is a modified idtech 3 engine with a idtech 4 type renderer. my recent baked texture for this model is 3072x1024 pixels and i used to split it up into three 1024x1024 size textures but i'm wondering if i could leave it at it's larger size?

what are the pros and cons of one larger texture on todays gpu's compared to several smaller ones?

[kat]

Most of the current generation of GFX cards can handle 4096 iirc, but that is a huge amount of data to be dedicating to a single individual element. You should be okay with the large size on more modern cards but I'd stay on the safe size and keep the 1024 break-down, even perhaps finding a way to use only unique data for the normals leaving the diffuse and specular to be tiled. If you need greater texture density you can always check to see if XReal supports the 'detail' stage in shaders (it should do being a QIII offshoot). Terrain objects are always a bit of a pain because you can never get enough detail in there for the size of texture you're using.

[ratty redemption]

thanks a lot kat, and i will do as you suggest.

the blender material i've set up for testing does use 256x256 tiled detail maps for normals and diffuse, the main diffuse and its spec are 1024x1024 which both tile, so really the only unique texture is the main normals.

i tried to dl the xreal version of the q3 shader manual but it's a .pdf and all the index links in it appear to be dead, so it's a pain to try and find the relevent info i was looking for. do you remember if there is a multiply type blend mode for the idtech 3 shaders? as that is what i'm using in blender for the diffuse details. also can detail normals be scaled and tiled in those shaders?

[kat]

Have a look through the QIII shader manual. You'll need info for XReal though because doing this all depends on their supporting it (or what feature they do have). One thing I'd watch out for it to make sure that you can blend detail normal maps in XReal, iirc D3 had problems with that so if they implemented a system based on that you might not be able to. Do they have a Wiki and/or support forum? Have a look there as well and see what you can find.

[ratty redemption]

thanks for the link kat, that web page manual is ideal for reference. i think the two lead guys i've been working with on the xreal project are both on holiday at the moment, as i couldn't get hold of them to ask specific xreal questions and their own forum didn't seem to have any info on the shaders, just the broken .pdf manual.

if the xreal blends greyscale heightmaps for normal detail like d3, do you know if those are scalable?

[kat]

Off hand no. A lot of this is going to depend on what XReal support so I'd see what you can find on their resources (otherwise you're pretty much flailing around in the dark trying to figure things out like we were in the very early days of the Doom 3 Alpha. Not fun!).

[ratty redemption]

good points, i'll continue to work with my setup in blender, and wait until i can get the weaver project guys to find out about the xreal shaders. i'll then update this topic for future reference.