private static double interp_XY_2(double x, double y, double xs, double ys, int x0, int x1, int y0, int y1,
uint seed, NoiseFunc noisefunc)
{
double v1 = interp_X_2(x, y, xs, x0, x1, y0, seed, noisefunc);
double v2 = interp_X_2(x, y, xs, x0, x1, y1, seed, noisefunc);
return(Lerp(ys, v1, v2));
}
private static double interp_X_2(double x, double y, double xs, int x0, int x1, int iy, uint seed,
NoiseFunc function)
{
double v1 = Noisefunc(x, y, x0, iy, seed, function);
double v2 = Noisefunc(x, y, x1, iy, seed, function);
return(Lerp(xs, v1, v2));
}
private static double noisefunc(double x, double y, int ix, int iy, uint seed, NoiseFunc function)
{
switch (function)
{
case NoiseFunc.value_noise_2: return value_noise_2(x, y, ix, iy, seed);
case NoiseFunc.grad_noise_2: return grad_noise_2(x, y, ix, iy, seed);
default: return value_noise_2(x, y, ix, iy, seed);
}
}
//public static double simplex_noise2D(double x, double y, int seed, InterpTypes interp)
//{
// double s = (x + y) * F2;
// int i=fast_floor(x+s);
// int j=fast_floor(y+s);
// double t = (i+j)*G2;
// double X0=i-t;
// double Y0=j-t;
// double x0=x-X0;
// double y0=y-Y0;
// int i1,j1;
// if(x0>y0)
// {
// i1=1; j1=0;
// }
// else
// {
// i1=0; j1=1;
// }
// double x1=x0-(double)i1+G2;
// double y1=y0-(double)j1+G2;
// double x2=x0-1.0+2.0*G2;
// double y2=y0-1.0+2.0*G2;
// // Hash the triangle coordinates to index the gradient table
// uint h0=hash_coords_2(i,j,seed);
// uint h1=hash_coords_2(i+i1,j+j1,seed);
// uint h2=hash_coords_2(i+1,j+1,seed);
// // Now, index the tables
// double g0 = gradient2D_lut[h0,0];
// double g1 = gradient2D_lut[h1,0];
// double g2 = gradient2D_lut[h2,0];
// double n0,n1,n2;
// // Calculate the contributions from the 3 corners
// double t0=0.5-x0*x0-y0*y0;
// if(t0<0) n0=0;
// else
// {
// t0 *= t0;
// n0 = t0 * t0 * array_dot2(g0,x0,y0);
// }
// double t1=0.5-x1*x1-y1*y1;
// if(t1<0) n1=0;
// else
// {
// t1*=t1;
// n1=t1*t1*array_dot2(g1,x1,y1);
// }
// double t2=0.5-x2*x2-y2*y2;
// if(t2<0) n2=0;
// else
// {
// t2*=t2;
// n2=t2*t2*array_dot2(g2,x2,y2);
// }
// // Add contributions together
// return (70.0 * (n0+n1+n2)) *1.42188695 + 0.001054489;
//}
static double interp_X_2(double x, double y, double xs, int x0, int x1, int iy, uint seed, NoiseFunc function)
{
double v1 = noisefunc(x, y, x0, iy, seed, function);
double v2 = noisefunc(x, y, x1, iy, seed, function);
return lerp(xs,v1,v2);
}
static double interp_XY_2(double x, double y, double xs, double ys, int x0, int x1, int y0, int y1, uint seed, NoiseFunc noisefunc)
{
double v1 = interp_X_2(x, y, xs, x0, x1, y0, seed, noisefunc);
double v2 = interp_X_2(x, y, xs, x0, x1, y1, seed, noisefunc);
return lerp(ys,v1,v2);
}
public Plane(float Width, int VertsPerSide, NoiseFunc NoiseFunction)
{
//The spacing between each of the vertices.
float Interp = Width / VertsPerSide;
//Half the width
float hWidth = Width * 0.5f;
//Number of indices
int NumIndices = (VertsPerSide - 1) * (VertsPerSide - 1) * 6;
Vertices = new Vector3[VertsPerSide * VertsPerSide];
Normals = new Vector3[VertsPerSide * VertsPerSide];
Indices = new int[NumIndices];
//Create and displace vertices
//Vertices are dispalced along the Y axis
//Doing this in 3d wold normally be more complicated but with a plane it is simple
Parallel.For(0, VertsPerSide, x =>
{
for (int z = 0; z < VertsPerSide; z++)
{
Vertices[x * VertsPerSide + z] = new Vector3(Interp * x - hWidth, NoiseFunction(Interp * x - hWidth, 0, Interp * z - hWidth), Interp * z - hWidth);
}
});
int idx = 0;
//Create indices
for (int y = 0; y < VertsPerSide - 1; y++)
{
for (int x = 0; x < VertsPerSide - 1; x++)
{
//First triangle
Indices[idx++] = (y + 1) * VertsPerSide + x;
Indices[idx++] = y * VertsPerSide + x + 1;
Indices[idx++] = (y * VertsPerSide + x);
//Second triangle
Indices[idx++] = (y + 1) * VertsPerSide + x;
Indices[idx++] = (y + 1) * VertsPerSide + x + 1;
Indices[idx++] = y * VertsPerSide + x + 1;
}
}
//Create normals using vector cross product
for (int i = 0; i < idx; i += 3)
{
Vector3 v0 = Vertices[Indices[i]];
Vector3 v1 = Vertices[Indices[i + 1]];
Vector3 v2 = Vertices[Indices[i + 2]];
Vector3 Normal = Vector3.Cross(v0 - v1, v0 - v2);
Normals[Indices[i]] += Normal;
Normals[Indices[i + 1]] += Normal;
Normals[Indices[i + 2]] += Normal;
}
//Normalize all the normals
for(int i = 0; i < Normals.Length; i++)
{
Normals[i].Normalize();
}
}
public Function(NoiseFunc Func)
{
this.Func = Func;
}
private static double Noisefunc(double x, double y, int ix, int iy, uint seed, NoiseFunc function)
{
switch (function)
{
case NoiseFunc.value_noise_2:
return(value_noise_2(x, y, ix, iy, seed));
case NoiseFunc.grad_noise_2:
return(grad_noise_2(x, y, ix, iy, seed));
default:
return(value_noise_2(x, y, ix, iy, seed));
}
}
public Function(NoiseFunc Func)
{
this.Func = Func;
}