I have been working on a Fixed-Function texture stage effect for mulit-texturing terrain. This is meant to be a fallback in the pixelshaders and also as an alternative.

This is using a 2 pass effect to keep stages under (2) in each pass. The textures are tiled using the texture transform matrix. The sand texture is blended using the alpha channel of a TGA.

I have included some fallback techniques, do not know if they are actually needed but I was having fun playing with this. I also may not be able test the fallbacks correctly. Feedback here, please.

This is done on 3DGameStudio A6.20.2 comm with a Radeon 9200 128 MB.

Goto my web site to get the Effect File, the Demo, or other info



This is adding another pass with a different alphamap and texture:



Please post mods, improvements, and if it does not work on your card please post the info pertaining to your card so I can know/learn.

Eric

I get the Default Effect on a Geforce 4 Ti 4400 (1.3 Pixel Shaders).

Thanks for letting me know!! Hope it works on a wide array of cards.

Note:
The downloadable demo does not have the pass with the grey cracked crap. It should look like the first screenshot.

Eric

hey really great job steem!
the default worked for me too, with my nvidia geforce 4 go 64 (thats the mx version which doesn't support many shaders..)


but there are some graphic errors, some parts of the terrain seem to transparent.. have a look on this :

We'll have to fiddle with it.
I don't get that problem here, so it will be hard to troubleshoot.

Where does your alphamap live? Is it an entSkin or a mtlSkin?
Could you try adding the "my.tranparent=off" to your action, just in case?

Maybe try adding "zenable=true"

technique ffp_terrain_tex
{
pass P0
{

alphablendenable=false;
zenable=true; //<<<<<<<<<<<<<<<<

If need be can I get a publish of that level and see how it runs on my card?

I'll think on it a bit and get back to you in a Private message.

Eric

hey, great job. this works on a geforce2. this could be real helpfull fallback for my current work. thx for sharing your worx .

@ello: Thanks, this is good news.

@makai:
I had weird results with the textures if put the alphaTGA in the entSkins. I kept them as mtlSkins.

Lets see.... you could try adding the new things ("//<<<<<<< NEW") in the code, and playing with that. This might give you a start in a direction to tinker with it.

Let me know what happens so I can update the demo if need be before too many people get a hold of it.

technique ffp_terrain_tex
{
pass P0
{

alphablendenable=false;
alphatestenable=false; //<<<<<<< NEW
zenable=true; //<<<<<<< NEW
zwriteenable=true; //<<<<<<< NEW
cullmode=none; //<<<<<<< NEW
//
// Stage 0
//
Texture[0] = <entSkin1>;

magFilter[0]=linear;
minFilter[0]=linear;
mipFilter[0]=linear;




TextureTransformFlags[0] = Count2;
TextureTransform[0] = <matMtl>;
texcoordindex[0]=0;

ColorArg1[0] = Texture;
ColorOp[0] = selectarg1;

alphaop[0]=disable;

//
//stage 1
//
colorop[1]=disable;
alphaop[1]=disable;

}

pass P1
{

// We need to enable alphablending

alphablendenable=true;
srcblend=srcalpha;
destblend=invsrcalpha;
alphatestenable=true; //<<<<<<< NEW
cullmode=none; //<<<<<<< NEW
zenable=false; //<<<<<<< NEW
zwriteenable=false; //<<<<<<< NEW

//
// Stage 0
//
Texture[0] = <mtlSkin2>;

magFilter[0]=linear;
minFilter[0]=linear;
mipFilter[0]=linear;

//
// We don't want the alphamap to tile
//
TextureTransformFlags[0] = disable;

texcoordindex[0]=1;

ColorArg1[0] = current;
ColorOp[0] = selectarg1;
alphaarg1[0] = texture | alphareplicate;
alphaop[0]=selectarg1;

//
// Stage 1
//
Texture[1] = <entSkin2>;//sand

cullmode=none; //<<<<<<< NEW
zenable=true; //<<<<<<< NEW
zwriteenable=true; //<<<<<<< NEW

magFilter[1]=linear;
minFilter[1]=linear;
mipFilter[1]=linear;


TextureTransformFlags[1] = Count2;
TextureTransform[1] = <matMtl>;
texcoordindex[1]=0;

ColorArg1[1] = texture;
ColorOp[1] = modulate;
alphaarg1[1] = current | alphareplicate;
alphaop[1]=disable;

//
// Stage 2
//
colorop[2]=disable;
alphaop[2]=disable;


}


Eric

you could add it to the wiki!

...
i think cullmode=none; just makes it slower and shouldn't be used.

Thats a good tip, leaving out cullmode, it is not necessary on my machine. Maybe everyone should leave that out. The code above is mainly for Makai to fiddle with and see if it can work.

Do you have any other suggestions?? You see, the thing ran fine on my card, but you see what happened on Makai's. What about the other things added in the "//<<<<<< NEW". I'm just learning, so most things are trial and error.

About the wiki, I am hoping that the code can be applicable across a varity of cards first. Needs testing and feedback. I am not going to change the code that is on the demo unless alot of people have problems. It will just get too confusing.

Thanks,
Eric

Excellent work, Steempipe!

I even tried it on my old pc with a 32mb Radeon 7500 card and it worked great!