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#import <Alpaca/Model/ALMap_TerrainGeneration.h> @implementation ALMap (TerrainGeneration) - (void)equalizeHeightmap:(double **)aHeightmap { // Calculate total weight double weight = 0.0; for(int x = 0; x < width; ++x) for(int y = 0; y < height; ++y) weight += aHeightmap[x][y]; // Calculate shift double shift = weight/(width*height); // Shift map for(int x = 0; x < width; ++x) for(int y = 0; y < height; ++y) aHeightmap[x][y] -= shift; } - (void)smoothHeightmap:(double **)aHeightmap { // Create blurred heightmap double **smoothedHeightmap = malloc(width*sizeof(double *)); for(int x = 0; x < width; ++x) smoothedHeightmap[x] = malloc(height*sizeof(double)); // Blur for(int x = 0; x < width; ++x) { for(int y = 0; y < height; ++y) { UInt8 count = 0; double sum = 0; // TL if(x > 0 && y > 0) { ++count; sum += aHeightmap[x-1][y-1]; } // TC if(y > 0) { ++count; sum += aHeightmap[x][y-1]; } // TR if(x < width-1 && y > 0) { ++count; sum += aHeightmap[x+1][y-1]; } // ML if(x > 0) { ++count; sum += aHeightmap[x-1][y]; } // MC if(1) { ++count; sum += aHeightmap[x][y]; } // MR if(x < width-1) { ++count; sum += aHeightmap[x+1][y]; } // BL if(x > 0 && y < height-1) { ++count; sum += aHeightmap[x-1][y+1]; } // BC if(y < height-1) { ++count; sum += aHeightmap[x][y+1]; } // BR if(x < width-1 && y < height-1) { ++count; sum += aHeightmap[x+1][y+1]; } // Calculate average smoothedHeightmap[x][y] = sum/(double)count; } } // Copy heightmap for(int x = 0; x < width; ++x) for(int y = 0; y < height; ++y) aHeightmap[x][y] = smoothedHeightmap[x][y]; } - (double)randomNumberWithWeight:(double)aWeight { return ((((double)random()) / (double)INT_MAX) - 0.5l) * aWeight; } - (void)randomizeHeightmapUsingSquares:(double **)aHeightmap { UInt16 iterations = 1000; UInt8 maxSize = 100; double weightModifier = 0.01; // Clear for(int x = 0; x < width; ++x) for(int y = 0; y < height; ++y) aHeightmap[x][y] = 0.0; for(int i = 0; i < iterations; ++i) { int randomX = (int)((((double)random()) / (double)INT_MAX) * width); int randomY = (int)((((double)random()) / (double)INT_MAX) * height); int randomSize = (int)((((double)random()) / (double)INT_MAX) * maxSize); double randomWeight = weightModifier * (((((double)random()) / (double)INT_MAX) - 0.5l) * maxSize); for(int x = randomX - randomSize; x < randomX + randomSize; ++x) { if(x < 0) continue; if(x >= width) continue; for(int y = randomY - randomSize; y < randomY + randomSize; ++y) { if(y < 0) continue; if(y >= height) continue; aHeightmap[x][y] += randomWeight * ((randomX + randomY) - (x + y)); } } } } - (void)randomizeHeightmapUsingMPD:(double **)aHeightmap { // Clear for(int x = 0; x < width; ++x) for(int y = 0; y < height; ++y) aHeightmap[x][y] = 0.0; // Set corner heights aHeightmap[0][0] = ((((double)random()) / (double)INT_MAX) - 0.5l) * 300.0; aHeightmap[0][height-1] = ((((double)random()) / (double)INT_MAX) - 0.5l) * 300.0; aHeightmap[width-1][0] = ((((double)random()) / (double)INT_MAX) - 0.5l) * 300.0; aHeightmap[width-1][height-1] = ((((double)random()) / (double)INT_MAX) - 0.5l) * 300.0; // Randomize [self randomizeHeightmapUsingMPD:aHeightmap from:MOMakePoint(0, 0) to:MOMakePoint(width-1, height-1)]; } - (void)randomizeHeightmapUsingMPD:(double **)aHeightmap from:(MOPoint)aSrc to:(MOPoint)aDst { [self randomizeHeightmapUsingMPD:aHeightmap from:aSrc to:aDst depth:0]; } - (void)randomizeHeightmapUsingMPD:(double **)aHeightmap from:(MOPoint)aSrc to:(MOPoint)aDst depth:(UInt8)aDepth { // Get relevant X coords UInt16 lX = aSrc.x; UInt16 mX = (aSrc.x + aDst.x)/2; UInt16 rX = aDst.x; // Get relevant Y coords UInt16 tY = aSrc.y; UInt16 mY = (aSrc.y + aDst.y)/2; UInt16 bY = aDst.y; // Get width/height UInt16 w = aDst.x - aSrc.x + 1; UInt16 h = aDst.y - aSrc.y + 1; // Configuration double weight = 300.0; // Get shortcut double **hm = aHeightmap; // Calculate center if(w >= 3 && h >= 3) { hm[mX][mY] = (hm[lX][tY] + hm[rX][tY] + hm[rX][bY] + hm[lX][bY])/4; hm[mX][mY] += [self randomNumberWithWeight:weight / (double)(1 + aDepth*aDepth)]; } // Calculate edges if(w >= 3) { // top hm[mX][tY] = (hm[lX][tY] + hm[rX][tY])/2; hm[mX][tY] += ((((double)random()) / (double)INT_MAX) - 0.5l) * weight / (double)(1 + aDepth*aDepth); // bottom hm[mX][bY] = (hm[lX][bY] + hm[rX][bY])/2; hm[mX][bY] += ((((double)random()) / (double)INT_MAX) - 0.5l) * weight / (double)(1 + aDepth*aDepth); } if(h >= 3) { // right hm[rX][mY] = (hm[rX][tY] + hm[rX][bY])/2; hm[rX][mY] += ((((double)random()) / (double)INT_MAX) - 0.5l) * weight / (double)(1 + aDepth*aDepth); // left hm[lX][mY] = (hm[lX][tY] + hm[lX][bY])/2; hm[lX][mY] += ((((double)random()) / (double)INT_MAX) - 0.5l) * weight / (double)(1 + aDepth*aDepth); } // Divide and conquer if(w > 3 && h <= 3) { // Divide vertically [self randomizeHeightmapUsingMPD:hm from:MOMakePoint(lX, tY) to:MOMakePoint(mX, bY) depth:aDepth+1]; [self randomizeHeightmapUsingMPD:hm from:MOMakePoint(mX, tY) to:MOMakePoint(rX, bY) depth:aDepth+1]; } else if(w <= 3 && h > 3) { // Divide horizontally [self randomizeHeightmapUsingMPD:hm from:MOMakePoint(lX, tY) to:MOMakePoint(rX, mY) depth:aDepth+1]; [self randomizeHeightmapUsingMPD:hm from:MOMakePoint(lX, mY) to:MOMakePoint(rX, bY) depth:aDepth+1]; } else if(w > 3 && h > 3) { // Divide in four [self randomizeHeightmapUsingMPD:hm from:MOMakePoint(lX, tY) to:MOMakePoint(mX, mY) depth:aDepth+1]; [self randomizeHeightmapUsingMPD:hm from:MOMakePoint(mX, tY) to:MOMakePoint(rX, mY) depth:aDepth+1]; [self randomizeHeightmapUsingMPD:hm from:MOMakePoint(lX, mY) to:MOMakePoint(mX, bY) depth:aDepth+1]; [self randomizeHeightmapUsingMPD:hm from:MOMakePoint(mX, mY) to:MOMakePoint(rX, bY) depth:aDepth+1]; } } @end

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