hedgewars/uLandGenPerlin.pas
changeset 10181 4708343d5963
child 10182 9d34898b22f7
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/hedgewars/uLandGenPerlin.pas	Fri Mar 07 23:36:56 2014 +0400
@@ -0,0 +1,137 @@
+{$INCLUDE "options.inc"}
+
+unit uLandGenPerlin;
+interface
+
+procedure GenPerlin;
+
+implementation
+uses uVariables, uConsts, math; // for min()
+
+var fadear: array[byte] of LongInt;
+    p: array[0..511] of LongInt;
+
+function fade(t: LongInt) : LongInt;
+var t0, t1: LongInt;
+begin
+    t0:= fadear[t shr 8];
+    t1:= fadear[min(255, t shr 8 + 1)];
+
+    fade:= t0 + ((t and 255) * (t1 - t0) shr 8)
+end;
+
+
+function lerp(t, a, b: LongInt) : LongInt;
+begin
+    lerp:= a + (t * (b - a) shr 12)
+end;
+
+
+function grad(hash, x, y, z: LongInt) : LongInt;
+var h, v, u: LongInt;
+begin
+    h:= hash and 15;
+    if h < 8 then u:= x else u:= y;
+    if h < 4 then v:= y else
+        if (h = 12) or (h = 14) then v:= x else v:= z;
+
+    if odd(h) then u:= -u;
+    if odd(h shr 1) then v:= -v;
+
+    grad:= u + v
+end;
+
+
+function inoise(x, y, z: LongInt) : LongInt;
+const N = $10000;
+var xx, yy, zz, u, v, w, A, AA, AB, B, BA, BB: LongInt;
+begin
+    xx:= (x shr 16) and 255;
+    yy:= (y shr 16) and 255;
+    zz:= (z shr 16) and 255;
+
+    x:= x and $FFFF;
+    y:= y and $FFFF;
+    z:= z and $FFFF;
+
+    u:= fade(x);
+    v:= fade(y);
+    w:= fade(z);
+
+    A:= p[xx    ] + yy; AA:= p[A] + zz; AB:= p[A + 1] + zz;
+    B:= p[xx + 1] + yy; BA:= p[B] + zz; BB:= p[B + 1] + zz;
+
+    inoise:=
+ lerp(w, lerp(v, lerp(u, grad(p[AA  ], x   , y   , z   ),
+                                     grad(p[BA  ], x-N , y   , z   )),
+                             lerp(u, grad(p[AB  ], x   , y-N , z   ),
+                                     grad(p[BB  ], x-N , y-N , z   ))),
+                     lerp(v, lerp(u, grad(p[AA+1], x   , y   , z-N ),
+                                     grad(p[BA+1], x-N , y   , z-N )),
+                             lerp(u, grad(p[AB+1], x   , y-N , z-N ),
+                                     grad(p[BB+1], x-N , y-N , z-N ))));
+end;
+
+function f(t: double): double;
+begin
+    f:= t * t * t * (t * (t * 6 - 15) + 10);
+end;
+
+const permutation: array[byte] of LongInt = ( 151,160,137,91,90,15,
+   131,13,201,95,96,53,194,233,7,225,140,36,103,30,69,142,8,99,37,240,21,10,23,
+   190, 6,148,247,120,234,75,0,26,197,62,94,252,219,203,117,35,11,32,57,177,33,
+   88,237,149,56,87,174,20,125,136,171,168, 68,175,74,165,71,134,139,48,27,166,
+   77,146,158,231,83,111,229,122,60,211,133,230,220,105,92,41,55,46,245,40,244,
+   102,143,54, 65,25,63,161, 1,216,80,73,209,76,132,187,208, 89,18,169,200,196,
+   135,130,116,188,159,86,164,100,109,198,173,186, 3,64,52,217,226,250,124,123,
+   5,202,38,147,118,126,255,82,85,212,207,206,59,227,47,16,58,17,182,189,28,42,
+   223,183,170,213,119,248,152, 2,44,154,163, 70,221,153,101,155,167, 43,172,9,
+   129,22,39,253, 19,98,108,110,79,113,224,232,178,185, 112,104,218,246,97,228,
+   251,34,242,193,238,210,144,12,191,179,162,241, 81,51,145,235,249,14,239,107,
+   49,192,214, 31,181,199,106,157,184, 84,204,176,115,121,50,45,127, 4,150,254,
+   138,236,205,93,222,114,67,29,24,72,243,141,128,195,78,66,215,61,156,180
+   );
+
+procedure inoise_setup();
+var i: LongInt;
+begin
+    for i:= 0 to 255 do
+        begin
+        p[256 + i]:= permutation[i];
+        p[i]:= permutation[i]
+        end;
+
+    for i:= 0 to 255 do
+        fadear[i]:= trunc($1000 * f(i / 256));
+end;
+
+const detail = 120000*3;
+    field = 3;
+    width = 4096;
+    height = 2048;
+
+procedure GenPerlin;
+var y, x, di, dj, r: LongInt;
+begin
+    inoise_setup();
+
+    for y:= 0 to pred(height) do
+    begin
+        di:= detail * field * y div height;
+        for x:= 0 to pred(width) do
+        begin
+            dj:= detail * field * x div width;
+            r:= (abs(inoise(di, dj, detail*field)) + y*4) mod 65536 div 256;
+            r:= r - max(0, abs(x - width div 2) - width * 45 div 100);
+            //r:= r - max(0, - abs(x - width div 2) + width * 2 div 100);
+
+
+            r:= r + (trunc(1000 - sqrt(sqr(x - (width div 2)) * 4 + sqr(y - height * 5 div 4) * 22))) div 600 * 20;
+
+            if r < 0 then Land[y, x]:= 0 else Land[y, x]:= lfBasic;
+
+        end;
+    end;
+end;
+
+end.