public override double this[double x, double y, double z]
{
get
{
// Get the output value from the source module.
double sourceModuleValue = ConnectedModule[x, y, z];
IList <double> inputs = controlPoints.Keys;
IList <double> outputs = controlPoints.Values;
// Find the first element in the control point array that has an input value
// larger than the output value from the source module.
int indexPos;
for (indexPos = 0; indexPos < controlPoints.Count; indexPos++)
{
if (sourceModuleValue < inputs[indexPos])
{
break;
}
}
// Find the four nearest control points so that we can perform cubic
// interpolation.
int index0 = Misc.ClampValue(indexPos - 2, 0, controlPoints.Count - 1);
int index1 = Misc.ClampValue(indexPos - 1, 0, controlPoints.Count - 1);
int index2 = Misc.ClampValue(indexPos, 0, controlPoints.Count - 1);
int index3 = Misc.ClampValue(indexPos + 1, 0, controlPoints.Count - 1);
// If some control points are missing (which occurs if the value from the
// source module is greater than the largest input value or less than the
// smallest input value of the control point array), get the corresponding
// output value of the nearest control point and exit now.
if (index1 == index2)
{
return(outputs[index1]);
}
// Compute the alpha value used for cubic interpolation.
double input0 = inputs[index1];
double input1 = inputs[index2];
double alpha = (sourceModuleValue - input0) / (input1 - input0);
// Now perform the cubic interpolation given the alpha value.
return(Interp.CubicInterp(
outputs[index0], outputs[index1], outputs[index2], outputs[index3],
alpha));
}
}