Specular shader chunk

Gnomo · 2019-02-12 16:27:31 UTC

Hello, i want to apply more than one metalic map to a material.
So i can have multiple stripes of “metal” in a model. And also remove them individually.

I added color stripes editing this chunk.

github.com

playcanvas/engine/blob/master/src/graphics/program-lib/chunks/diffuse.frag

#ifdef MAPCOLOR
uniform vec3 material_diffuse;
#endif

#ifdef MAPTEXTURE
uniform sampler2D texture_diffuseMap;
#endif

void getAlbedo() {
    dAlbedo = vec3(1.0);

    #ifdef MAPCOLOR
        dAlbedo *= material_diffuse.rgb;
    #endif

    #ifdef MAPTEXTURE
        dAlbedo *= texture2DSRGB(texture_diffuseMap, $UV).$CH;
    #endif

    #ifdef MAPVERTEX

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But i cant do the same for this chunk https://github.com/playcanvas/engine/blob/master/src/graphics/program-lib/chunks/metalness.frag

I believe my problem is i dont know what to override.
In the diffuse was this.material.chunks.diffusePS = this.shader_diffuseConstPS.resource.
Of course if a override the diffusePS with a specular gives an error. But i tried specularPS and other variations and it gets ignored.

Clearly i am really ignorant in this topic. But i dont know where to look for more info.

Thanks.

kindy77 · 2019-02-13 16:47:21 UTC

Pardon my ignorance on your project, but wouldn’t it be a bit easier to just have one material with a varying metalness and specular map to fake two or more different metals?

Gnomo · 2019-02-13 18:27:09 UTC

For sure that sounds easier, but how you assign one material with more than one metalness?