--------------------------------------
| 49 | |
| 50 | //-------------------------------------- |
| 51 | void Noise2D::setSeed(U32 seed) |
| 52 | { |
| 53 | if (mSeed == seed) |
| 54 | return; |
| 55 | mSeed = seed; |
| 56 | mRandom.setSeed(mSeed); |
| 57 | |
| 58 | S32 i, j, k; |
| 59 | |
| 60 | for (i = 0 ; i < SIZE ; i++) { |
| 61 | mPermutation[i] = i; |
| 62 | |
| 63 | for (j = 0 ; j < 2 ; j++) |
| 64 | mGradient[i][j] = mRandom.randF( -1.0f, 1.0f ); |
| 65 | normalize(mGradient[i]); |
| 66 | } |
| 67 | |
| 68 | while (--i) { |
| 69 | k = mPermutation[i]; |
| 70 | j = mRandom.randI(0, SIZE-1); |
| 71 | mPermutation[i] = mPermutation[j]; |
| 72 | mPermutation[j] = k; |
| 73 | } |
| 74 | |
| 75 | // extend the size of the arrays x2 to get rid of a bunch of MODs |
| 76 | // we'd have to do later in the code |
| 77 | for (i = 0 ; i < SIZE + 2 ; i++) { |
| 78 | mPermutation[SIZE + i] = mPermutation[i]; |
| 79 | for (j = 0 ; j < 2 ; j++) |
| 80 | mGradient[SIZE + i][j] = mGradient[i][j]; |
| 81 | } |
| 82 | } |
| 83 | |
| 84 | |
| 85 | //-------------------------------------- |