stjr/SRB2
0
0
Fork 0
mirror of https://git.do.srb2.org/STJr/SRB2.git synced 2025-04-22 02:01:04 +00:00
Code Issues Projects Releases Packages Wiki Activity

Clarify we're calculating a cross product

Browse source
This commit is contained in:
Gustaf Alhäll 2024-10-21 17:02:14 +02:00
parent dafaae65fb
commit b8dd0f69e7
1 changed files with 4 additions and 4 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

8
src/r_main.h
View file

@ -74,8 +74,8 @@ extern lighttable_t *zlight[LIGHTLEVELS][MAXLIGHTZ];
// Utility functions.
static inline INT32 R_PointOnSide(fixed_t x, fixed_t y, node_t *node)
{
// heavily optimized version of R_PointOnSide, stolen from GZDoom.
return (INT64)(y - node->y) * node->dx + (INT64)(node->x - x) * node->dy > 0;
// use cross product to determine side quickly
return (INT64)(y - node->y) * node->dx - (INT64)(x - node->x) * node->dy > 0;
}
static inline INT32 R_PointOnSegSide(fixed_t x, fixed_t y, seg_t *line)
@ -85,8 +85,8 @@ static inline INT32 R_PointOnSegSide(fixed_t x, fixed_t y, seg_t *line)
fixed_t ldx = line->v2->x - lx;
fixed_t ldy = line->v2->y - ly;
// heavily optimized version of R_PointOnSide, stolen from GZDoom.
return (INT64)(y - ly) * ldx + (INT64)(lx - x) * ldy > 0;
// use cross product to determine side quickly
return (INT64)(y - ly) * ldx - (INT64)(x - lx) * ldy > 0;
}
angle_t R_PointToAngle(fixed_t x, fixed_t y);