diff options
Diffstat (limited to 'common/common.c')
| -rw-r--r-- | common/common.c | 71 |
1 files changed, 63 insertions, 8 deletions
diff --git a/common/common.c b/common/common.c index e8a100dcc4..6607f95c3c 100644 --- a/common/common.c +++ b/common/common.c @@ -96,10 +96,10 @@ char *mp_format_time(double time, bool fractions) // Set rc to the union of rc and rc2 void mp_rect_union(struct mp_rect *rc, const struct mp_rect *rc2) { - rc->x0 = FFMIN(rc->x0, rc2->x0); - rc->y0 = FFMIN(rc->y0, rc2->y0); - rc->x1 = FFMAX(rc->x1, rc2->x1); - rc->y1 = FFMAX(rc->y1, rc2->y1); + rc->x0 = MPMIN(rc->x0, rc2->x0); + rc->y0 = MPMIN(rc->y0, rc2->y0); + rc->x1 = MPMAX(rc->x1, rc2->x1); + rc->y1 = MPMAX(rc->y1, rc2->y1); } // Returns whether or not a point is contained by rc @@ -112,10 +112,10 @@ bool mp_rect_contains(struct mp_rect *rc, int x, int y) // Return false if the result is empty. bool mp_rect_intersection(struct mp_rect *rc, const struct mp_rect *rc2) { - rc->x0 = FFMAX(rc->x0, rc2->x0); - rc->y0 = FFMAX(rc->y0, rc2->y0); - rc->x1 = FFMIN(rc->x1, rc2->x1); - rc->y1 = FFMIN(rc->y1, rc2->y1); + rc->x0 = MPMAX(rc->x0, rc2->x0); + rc->y0 = MPMAX(rc->y0, rc2->y0); + rc->x1 = MPMIN(rc->x1, rc2->x1); + rc->y1 = MPMIN(rc->y1, rc2->y1); return rc->x1 > rc->x0 && rc->y1 > rc->y0; } @@ -126,6 +126,28 @@ bool mp_rect_equals(struct mp_rect *rc1, struct mp_rect *rc2) rc1->x1 == rc2->x1 && rc1->y1 == rc2->y1; } +// Compute rc1-rc2, put result in res_array, return number of rectangles in +// res_array. In the worst case, there are 4 rectangles, so res_array must +// provide that much storage space. +int mp_rect_subtract(const struct mp_rect *rc1, const struct mp_rect *rc2, + struct mp_rect res[4]) +{ + struct mp_rect rc = *rc1; + if (!mp_rect_intersection(&rc, rc2)) + return 0; + + int cnt = 0; + if (rc1->y0 < rc.y0) + res[cnt++] = (struct mp_rect){rc1->x0, rc1->y0, rc1->x1, rc.y0}; + if (rc1->x0 < rc.x0) + res[cnt++] = (struct mp_rect){rc1->x0, rc.y0, rc.x0, rc.y1}; + if (rc1->x1 > rc.x1) + res[cnt++] = (struct mp_rect){rc.x1, rc.y0, rc1->x1, rc.y1}; + if (rc1->y1 > rc.y1) + res[cnt++] = (struct mp_rect){rc1->x0, rc.y1, rc1->x1, rc1->y1}; + return cnt; +} + // This works like snprintf(), except that it starts writing the first output // character to str[strlen(str)]. This returns the number of characters the // string would have *appended* assuming a large enough buffer, will make sure @@ -318,3 +340,36 @@ char **mp_dup_str_array(void *tctx, char **s) MP_TARRAY_APPEND(tctx, r, num_r, NULL); return r; } + +// Return rounded down integer log 2 of v, i.e. position of highest set bit. +// mp_log2(0) == 0 +// mp_log2(1) == 0 +// mp_log2(31) == 4 +// mp_log2(32) == 5 +unsigned int mp_log2(uint32_t v) +{ +#if defined(__GNUC__) && __GNUC__ >= 4 + return v ? 31 - __builtin_clz(v) : 0; +#else + for (int x = 31; x >= 0; x--) { + if (v & (((uint32_t)1) << x)) + return x; + } + return 0; +#endif +} + +// If a power of 2, return it, otherwise return the next highest one, or 0. +// mp_round_next_power_of_2(65) == 128 +// mp_round_next_power_of_2(64) == 64 +// mp_round_next_power_of_2(0) == 1 +// mp_round_next_power_of_2(UINT32_MAX) == 0 +uint32_t mp_round_next_power_of_2(uint32_t v) +{ + if (!v) + return 1; + if (!(v & (v - 1))) + return v; + int l = mp_log2(v) + 1; + return l == 32 ? 0 : (uint32_t)1 << l; +} |