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- // rndmap.cpp: perlin noise landscape generation and some experimental random map stuff, currently not used
-
- #include "cube.h"
-
- float noise(int x, int y, int seed)
- {
- int n = x+y*57;
- n = (n<<13)^n;
- return 1.0f-((n*(n*n*15731+789221)+1376312589)&0x7fffffff)/1073741824.0f;
- }
-
- float smoothednoise(int x, int y, int seed)
- {
- float corners = (noise(x-1, y-1, seed)+noise(x+1, y-1, seed)+noise(x-1, y+1, seed)+noise(x+1, y+1, seed))/16;
- float sides = (noise(x-1, y, seed)+noise(x+1, y, seed)+noise(x, y-1, seed)+noise(x, y+1, seed))/8;
- float center = noise(x, y, seed)/4;
- return corners+sides+center;
- }
-
- float interpolate(float a, float b, float x)
- {
- float ft = x*3.1415927f;
- float f = (1.0f-cosf(ft))*0.5f;
- return a*(1-f)+b*f;
- }
-
- float interpolatednoise(float x, float y, int seed)
- {
- int ix = (int)x;
- float fx = x-ix;
- int iy = (int)y;
- float fy = y-iy;
- float v1 = smoothednoise(ix, iy, seed);
- float v2 = smoothednoise(ix+1, iy, seed);
- float v3 = smoothednoise(ix, iy+1, seed);
- float v4 = smoothednoise(ix+1, iy+1, seed);
- float i1 = interpolate(v1, v2, fx);
- float i2 = interpolate(v3, v4, fy);
- return interpolate(i1, i2, fy);
- }
-
- float perlinnoise_2D(float x, float y, int seedstep, float pers)
- {
- float total = 0;
- int seed = 0;
- for(int i = 0; i<7; i++)
- {
- float frequency = (float)(2^i);
- float amplitude = (float)pow(pers, i);
- total += interpolatednoise(x*frequency, y*frequency, seed)*amplitude;
- seed += seedstep;
- }
- return total;
- }
-
- void perlinarea(block &b, int scale, int seed, int psize)
- {
- srand(seed);
- seed = rnd(10000);
- if(!scale) scale = 10;
- for(int x = b.x; x<=b.x+b.xs; x++) for(int y = b.y; y<=b.y+b.ys; y++)
- {
- sqr *s = S(x,y);
- if(!SOLID(s) && x!=b.x+b.xs && y!=b.y+b.ys) s->type = FHF;
- s->vdelta = (int)(perlinnoise_2D(x/((float)scale)+seed, y/((float)scale)+seed, 1000, 0.01f)*50+25);
- if(s->vdelta>128) s->vdelta = 0;
- }
- }
-
-
-