griefith/test2
1
0
Fork 0
Code Issues Pull Requests Actions 1 Packages Projects Releases Wiki Activity

Cleanup: replace qsort with std::sort

Browse Source 
Also replace the PointRef struct with an integer array as this was
a workaround for `qsort` not taking additional arguments.
This commit is contained in:
Campbell Barton
2024-02-12 20:17:21 +11:00
parent f4f97ea979
commit 8f09fffef7
1 changed files with 24 additions and 33 deletions
Download Patch File Download Diff File Expand all files Collapse all files

57
source/blender/blenlib/intern/convexhull_2d.cc
View File

@@ -7,6 +7,7 @@
* \ingroup bli
*/
#include <algorithm>
#include <stdlib.h>
#include <string.h>
@@ -145,32 +146,6 @@ static int convexhull_2d_sorted(const float (*points)[2], const int points_num,
return top + 1;
}
struct PointRef {
/** 2D vector. */
const float *pt;
};
static int pointref_cmp_yx(const void *a_, const void *b_)
{
const PointRef *a = static_cast<const PointRef *>(a_);
const PointRef *b = static_cast<const PointRef *>(b_);
if (a->pt[1] > b->pt[1]) {
return 1;
}
if (a->pt[1] < b->pt[1]) {
return -1;
}
if (a->pt[0] > b->pt[0]) {
return 1;
}
if (a->pt[0] < b->pt[0]) {
return -1;
}
return 0;
}
int BLI_convexhull_2d(const float (*points)[2], const int points_num, int r_points[])
{
BLI_assert(points_num >= 0);
@@ -180,30 +155,46 @@ int BLI_convexhull_2d(const float (*points)[2], const int points_num, int r_poin
}
return points_num;
}
PointRef *points_ref = static_cast<PointRef *>(
MEM_mallocN(sizeof(*points_ref) * size_t(points_num), __func__));
int *points_map = static_cast<int *>(MEM_mallocN(sizeof(int) * size_t(points_num), __func__));
float(*points_sort)[2] = static_cast<float(*)[2]>(
MEM_mallocN(sizeof(*points_sort) * size_t(points_num), __func__));
for (int i = 0; i < points_num; i++) {
points_ref[i].pt = points[i];
points_map[i] = i;
}
/* Sort the points by X, then by Y. */
qsort(points_ref, size_t(points_num), sizeof(PointRef), pointref_cmp_yx);
std::sort(points_map, points_map + points_num, [points](const int &a_index, const int &b_index) {
const float *a = points[a_index];
const float *b = points[b_index];
if (a[1] > b[1]) {
return false;
}
if (a[1] < b[1]) {
return true;
}
if (a[0] > b[0]) {
return false;
}
if (a[0] < b[0]) {
return true;
}
return false;
});
for (int i = 0; i < points_num; i++) {
memcpy(points_sort[i], points_ref[i].pt, sizeof(float[2]));
copy_v2_v2(points_sort[i], points[points_map[i]]);
}
int points_hull_num = convexhull_2d_sorted(points_sort, points_num, r_points);
/* Map back to the unsorted index values. */
for (int i = 0; i < points_hull_num; i++) {
r_points[i] = int((const float(*)[2])points_ref[r_points[i]].pt - points);
r_points[i] = points_map[r_points[i]];
}
MEM_freeN(points_ref);
MEM_freeN(points_map);
MEM_freeN(points_sort);
BLI_assert(points_hull_num <= points_num);