diff options
Diffstat (limited to 'source/blender/blenkernel/intern/particle_distribute.c')
| -rw-r--r-- | source/blender/blenkernel/intern/particle_distribute.c | 23 |
1 files changed, 13 insertions, 10 deletions
diff --git a/source/blender/blenkernel/intern/particle_distribute.c b/source/blender/blenkernel/intern/particle_distribute.c index f6bddfa6f99..0d7fe04a1e4 100644 --- a/source/blender/blenkernel/intern/particle_distribute.c +++ b/source/blender/blenkernel/intern/particle_distribute.c @@ -392,22 +392,25 @@ static int distribute_binary_search(float *sum, int n, float value) { int mid, low = 0, high = n - 1; + if (high == low) + return low; + if (sum[low] >= value) return low; - if (sum[high] < value) + if (sum[high - 1] < value) return high; while (low < high) { mid = (low + high) / 2; - if ((sum[mid] < value) && (sum[mid + 1] >= value)) + if ((sum[mid] >= value) && (sum[mid - 1] < value)) return mid; - if (sum[mid] >= value) { + if (sum[mid] > value) { high = mid - 1; } - else if (sum[mid] < value) { + else { low = mid + 1; } } @@ -1024,7 +1027,7 @@ static int psys_thread_context_init_distribute(ParticleThreadContext *ctx, Parti /* Calculate cumulative weights. * We remove all null-weighted elements from element_sum, and create a new mapping * 'activ'_elem_index -> orig_elem_index. - * This simplifies greatly the filtering of zero-weighted items - and can be much mor efficient + * This simplifies greatly the filtering of zero-weighted items - and can be much more efficient * especially in random case (reducing a lot the size of binary-searched array)... */ float *element_sum = MEM_mallocN(sizeof(*element_sum) * totmapped, __func__); @@ -1047,13 +1050,13 @@ static int psys_thread_context_init_distribute(ParticleThreadContext *ctx, Parti /* Finally assign elements to particles */ if ((part->flag & PART_TRAND) || (part->simplify_flag & PART_SIMPLIFY_ENABLE)) { - float pos; - for (p = 0; p < totpart; p++) { - /* In theory element_sum[totelem - 1] should be 1.0, + /* In theory element_sum[totmapped - 1] should be 1.0, * but due to float errors this is not necessarily always true, so scale pos accordingly. */ - pos = BLI_frand() * element_sum[totmapped - 1]; - particle_element[p] = element_map[distribute_binary_search(element_sum, totmapped, pos)]; + const float pos = BLI_frand() * element_sum[totmapped - 1]; + const int eidx = distribute_binary_search(element_sum, totmapped, pos); + particle_element[p] = element_map[eidx]; + BLI_assert(pos <= element_sum[eidx] && pos > (eidx ? element_sum[eidx - 1] : 0.0f)); jitter_offset[particle_element[p]] = pos; } } |