VEX: Ramp parameter code. Spline function?

[evgen]

Hello.

I have the problem with using ramp parameter in vex.

What code should i use for get it works?

Seems that i need to use spline() with a few arrays of values, as in the help, but compiler gives me a lot of errors with it.

How i need to use spline function for this?

Thank you

[symek]

You would have to be more specific about errors, but generally, since ramps are tedious to setup, what I usually do is that I copy code from any of SESI shaders with ramps . ASAD light for example:

/*
 * PROPRIETARY INFORMATION.  This software is proprietary to

(...)


#pragma ramp_rgb        atten_ramp atten_basis atten_keys atten_values
#pragma parmtag         atten_ramp rampbasisdefault linear
#pragma parmtag         atten_ramp rampshowcontrolsdefault 0
#pragma parmtag         atten_ramp rampcolortype rgb
(...)

vector
eval_ramp(float t0; string basis[]; float keys[]; vector values[])
{
    return spline(basis, spline("linearsolve", t0, keys), values);
}

(...)

string atten_basis[] = {"linear", "linear", "linear"};
float  atten_keys[] = {0.0, 0.9, 1.0};
vector atten_values[] = {{1,1,1}, {1,1,1}, {0,0,0}};
(...)

 Cl *= eval_ramp(key, atten_basis, atten_keys, atten_values);

Edited March 22, 2012 by SYmek

[evgen]

Thanks SYmek. Thats correct, i found this solution after posting this thread)

Maybe sombody find this information useful too.

Thanks again