AstralTransRocketries/ClassiCube
1
0
Fork 0
mirror of https://github.com/ClassiCube/ClassiCube.git synced 2025-09-16 11:06:06 -04:00
Code Issues Packages Projects Releases Wiki Activity

Optimise noise calculation to be slightly faster on very large worlds.

Browse Source
This commit is contained in:
UnknownShadow200 2016-02-02 15:40:18 +11:00
parent 11d8a04527
commit c4a2bd0517
1 changed files with 11 additions and 24 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

35
ClassicalSharp/Generator/Noise.cs
View File

@ -35,36 +35,23 @@ namespace ClassicalSharp.Generator {
double u = x * x * x * (x * (x * 6 - 15) + 10); // Fade(x)
double v = y * y * y * (y * (y * 6 - 15) + 10); // Fade(y)
int A = p[X] + Y, B = p[X + 1] + Y;
const int xFlags = 0x46552222, yFlags = 0x2222550A;
double g22 = Grad( p[p[A]], x, y ), g12 = Grad( p[p[B]], x - 1, y );
int hash = (p[p[A]] & 0xF) << 1;
double g22 = (((xFlags >> hash) & 3) - 1) * x + (((yFlags >> hash) & 3) - 1) * y; // Grad(p[p[A], x, y)
hash = (p[p[B]] & 0xF) << 1;
double g12 = (((xFlags >> hash) & 3) - 1) * (x - 1) + (((yFlags >> hash) & 3) - 1) * y; // Grad(p[p[B], x - 1, y)
double c1 = g22 + u * (g12 - g22);
double g21 = Grad( p[p[A + 1]], x, y - 1 ), g11 = Grad( p[p[B + 1]], x - 1, y - 1 );
hash = (p[p[A + 1]] & 0xF) << 1;
double g21 = (((xFlags >> hash) & 3) - 1) * x + (((yFlags >> hash) & 3) - 1) * (y - 1); // Grad(p[p[A + 1], x, y - 1)
hash = (p[p[B + 1]] & 0xF) << 1;
double g11 = (((xFlags >> hash) & 3) - 1) * (x - 1) + (((yFlags >> hash) & 3) - 1) * (y - 1); // Grad(p[p[B + 1], x - 1, y - 1)
double c2 = g21 + u * (g11 - g21);
return c1 + v * (c2 - c1);
}
static double Grad( int hash, double x, double y ) {
switch( hash & 15 ) {
case 0: return x + y;
case 1: return -x + y;
case 2: return x - y;
case 3: return -x - y;
case 4: return x;
case 5: return -x;
case 6: return x;
case 7: return -x;
case 8: return y;
case 9: return -y;
case 10: return y;
case 11: return -y;
case 12: return x + y;
case 13: return -y;
case 14: return -x + y;
case 15: return -y;
default: return 0;
}
}
byte[] p = new byte[512];
}