disp_textured.sl.cpp

displacement disp_textured(
    float   Km      = 1.0,
            min_u   = 0.0,
            max_u   = 1.0,
            min_v   = 0.0,
            max_v   = 1.0;
    string  mapname = "")
{
    float   magnitude,
            level;

    if( mapname != "")
    {
        level = float 
            texture(
                mapname,
                (u - min_u) / (max_u - min_u),
                (v - min_v) / (max_v - min_v) );

/* DAVIDE - commenting this until vargarg is implemented

                "swidth", 0.0001,
                "twidth", 0.0001,
                "samples", 1);
*/
                
        magnitude   = ((level * 2) - 1) * Km;
    }
    else
    {
        magnitude   = 0.0;
    }

    /* DAVIDE - Changing to "proper" displacement (any difference ?)
    P   = P + normalize( N) * magnitude;
    */
    normal Nn = normalize( N );
    P   = P + Nn * magnitude / length( ntransform( "shader", Nn ) );
    
    N   = calculatenormal( P);
}