annotate src/video/SDL_rect.c @ 3282:10a12f77f597

Oh yeah, need this option for PPC as well now.
author Sam Lantinga <slouken@libsdl.org>
date Sun, 20 Sep 2009 04:13:23 +0000
parents 47965eacde88
children 0267b8b1595c
rev   line source
1895
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
1 /*
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
2 SDL - Simple DirectMedia Layer
2859
99210400e8b9 Updated copyright date
Sam Lantinga <slouken@libsdl.org>
parents: 2275
diff changeset
3 Copyright (C) 1997-2009 Sam Lantinga
1895
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
4
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
5 This library is free software; you can redistribute it and/or
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
6 modify it under the terms of the GNU Lesser General Public
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
7 License as published by the Free Software Foundation; either
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
8 version 2.1 of the License, or (at your option) any later version.
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
9
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
10 This library is distributed in the hope that it will be useful,
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
13 Lesser General Public License for more details.
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
14
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
15 You should have received a copy of the GNU Lesser General Public
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
16 License along with this library; if not, write to the Free Software
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
17 Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
18
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
19 Sam Lantinga
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
20 slouken@libsdl.org
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
21 */
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
22 #include "SDL_config.h"
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
23
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
24 #include "SDL_video.h"
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
25 #include "SDL_rect_c.h"
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
26
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
27 SDL_bool
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
28 SDL_HasIntersection(const SDL_Rect * A, const SDL_Rect * B)
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
29 {
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
30 int Amin, Amax, Bmin, Bmax;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
31
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
32 /* Horizontal intersection */
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
33 Amin = A->x;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
34 Amax = Amin + A->w;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
35 Bmin = B->x;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
36 Bmax = Bmin + B->w;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
37 if (Bmin > Amin)
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
38 Amin = Bmin;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
39 if (Bmax < Amax)
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
40 Amax = Bmax;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
41 if (Amax <= Amin)
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
42 return SDL_FALSE;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
43
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
44 /* Vertical intersection */
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
45 Amin = A->y;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
46 Amax = Amin + A->h;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
47 Bmin = B->y;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
48 Bmax = Bmin + B->h;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
49 if (Bmin > Amin)
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
50 Amin = Bmin;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
51 if (Bmax < Amax)
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
52 Amax = Bmax;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
53 if (Amax <= Amin)
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
54 return SDL_FALSE;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
55
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
56 return SDL_TRUE;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
57 }
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
58
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
59 SDL_bool
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
60 SDL_IntersectRect(const SDL_Rect * A, const SDL_Rect * B, SDL_Rect * result)
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
61 {
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
62 int Amin, Amax, Bmin, Bmax;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
63
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
64 /* Horizontal intersection */
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
65 Amin = A->x;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
66 Amax = Amin + A->w;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
67 Bmin = B->x;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
68 Bmax = Bmin + B->w;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
69 if (Bmin > Amin)
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
70 Amin = Bmin;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
71 result->x = Amin;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
72 if (Bmax < Amax)
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
73 Amax = Bmax;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
74 result->w = Amax - Amin;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
75
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
76 /* Vertical intersection */
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
77 Amin = A->y;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
78 Amax = Amin + A->h;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
79 Bmin = B->y;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
80 Bmax = Bmin + B->h;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
81 if (Bmin > Amin)
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
82 Amin = Bmin;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
83 result->y = Amin;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
84 if (Bmax < Amax)
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
85 Amax = Bmax;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
86 result->h = Amax - Amin;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
87
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
88 return !SDL_RectEmpty(result);
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
89 }
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
90
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
91 void
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
92 SDL_UnionRect(const SDL_Rect * A, const SDL_Rect * B, SDL_Rect * result)
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
93 {
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
94 int Amin, Amax, Bmin, Bmax;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
95
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
96 /* Horizontal union */
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
97 Amin = A->x;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
98 Amax = Amin + A->w;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
99 Bmin = B->x;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
100 Bmax = Bmin + B->w;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
101 if (Bmin < Amin)
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
102 Amin = Bmin;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
103 result->x = Amin;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
104 if (Bmax > Amax)
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
105 Amax = Bmax;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
106 result->w = Amax - Amin;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
107
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
108 /* Vertical intersection */
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
109 Amin = A->y;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
110 Amax = Amin + A->h;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
111 Bmin = B->y;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
112 Bmax = Bmin + B->h;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
113 if (Bmin < Amin)
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
114 Amin = Bmin;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
115 result->y = Amin;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
116 if (Bmax > Amax)
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
117 Amax = Bmax;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
118 result->h = Amax - Amin;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
119 }
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
120
2909
3da0bb421d83 Added line clipping
Sam Lantinga <slouken@libsdl.org>
parents: 2859
diff changeset
121 SDL_bool
2920
Sam Lantinga <slouken@libsdl.org>
parents: 2909
diff changeset
122 SDL_IntersectRectAndLine(const SDL_Rect * rect, int *X1, int *Y1, int *X2,
Sam Lantinga <slouken@libsdl.org>
parents: 2909
diff changeset
123 int *Y2)
2909
3da0bb421d83 Added line clipping
Sam Lantinga <slouken@libsdl.org>
parents: 2859
diff changeset
124 {
3da0bb421d83 Added line clipping
Sam Lantinga <slouken@libsdl.org>
parents: 2859
diff changeset
125 int x1, y1;
3da0bb421d83 Added line clipping
Sam Lantinga <slouken@libsdl.org>
parents: 2859
diff changeset
126 int x2, y2;
3da0bb421d83 Added line clipping
Sam Lantinga <slouken@libsdl.org>
parents: 2859
diff changeset
127 int rectx1;
3da0bb421d83 Added line clipping
Sam Lantinga <slouken@libsdl.org>
parents: 2859
diff changeset
128 int recty1;
3da0bb421d83 Added line clipping
Sam Lantinga <slouken@libsdl.org>
parents: 2859
diff changeset
129 int rectx2;
3da0bb421d83 Added line clipping
Sam Lantinga <slouken@libsdl.org>
parents: 2859
diff changeset
130 int recty2;
3da0bb421d83 Added line clipping
Sam Lantinga <slouken@libsdl.org>
parents: 2859
diff changeset
131
3da0bb421d83 Added line clipping
Sam Lantinga <slouken@libsdl.org>
parents: 2859
diff changeset
132 if (!rect || !X1 || !Y1 || !X2 || !Y2) {
3046
47965eacde88 Fix recommended by Eddy L O Jansson
Sam Lantinga <slouken@libsdl.org>
parents: 3004
diff changeset
133 return SDL_FALSE;
2909
3da0bb421d83 Added line clipping
Sam Lantinga <slouken@libsdl.org>
parents: 2859
diff changeset
134 }
3da0bb421d83 Added line clipping
Sam Lantinga <slouken@libsdl.org>
parents: 2859
diff changeset
135
3da0bb421d83 Added line clipping
Sam Lantinga <slouken@libsdl.org>
parents: 2859
diff changeset
136 x1 = *X1;
3da0bb421d83 Added line clipping
Sam Lantinga <slouken@libsdl.org>
parents: 2859
diff changeset
137 y1 = *Y1;
3da0bb421d83 Added line clipping
Sam Lantinga <slouken@libsdl.org>
parents: 2859
diff changeset
138 x2 = *X2;
3da0bb421d83 Added line clipping
Sam Lantinga <slouken@libsdl.org>
parents: 2859
diff changeset
139 y2 = *Y2;
3da0bb421d83 Added line clipping
Sam Lantinga <slouken@libsdl.org>
parents: 2859
diff changeset
140 rectx1 = rect->x;
3da0bb421d83 Added line clipping
Sam Lantinga <slouken@libsdl.org>
parents: 2859
diff changeset
141 recty1 = rect->y;
3da0bb421d83 Added line clipping
Sam Lantinga <slouken@libsdl.org>
parents: 2859
diff changeset
142 rectx2 = rect->x + rect->w - 1;
3da0bb421d83 Added line clipping
Sam Lantinga <slouken@libsdl.org>
parents: 2859
diff changeset
143 recty2 = rect->y + rect->h - 1;
3da0bb421d83 Added line clipping
Sam Lantinga <slouken@libsdl.org>
parents: 2859
diff changeset
144
3da0bb421d83 Added line clipping
Sam Lantinga <slouken@libsdl.org>
parents: 2859
diff changeset
145 /* Check to see if entire line is inside rect */
3da0bb421d83 Added line clipping
Sam Lantinga <slouken@libsdl.org>
parents: 2859
diff changeset
146 if (x1 >= rectx1 && x1 <= rectx2 && x2 >= rectx1 && x2 <= rectx2 &&
3da0bb421d83 Added line clipping
Sam Lantinga <slouken@libsdl.org>
parents: 2859
diff changeset
147 y1 >= recty1 && y1 <= recty2 && y2 >= recty1 && y2 <= recty2) {
3da0bb421d83 Added line clipping
Sam Lantinga <slouken@libsdl.org>
parents: 2859
diff changeset
148 return SDL_TRUE;
3da0bb421d83 Added line clipping
Sam Lantinga <slouken@libsdl.org>
parents: 2859
diff changeset
149 }
3da0bb421d83 Added line clipping
Sam Lantinga <slouken@libsdl.org>
parents: 2859
diff changeset
150
2994
7563b99e9a49 Date: Sat, 3 Jan 2009 22:11:18 -0500
Sam Lantinga <slouken@libsdl.org>
parents: 2920
diff changeset
151 /* Check to see if entire line is to one side of rect */
2909
3da0bb421d83 Added line clipping
Sam Lantinga <slouken@libsdl.org>
parents: 2859
diff changeset
152 if ((x1 < rectx1 && x2 < rectx1) || (x1 > rectx2 && x2 > rectx2) ||
3004
f3d7226a8dfd Fixed lines intersecting the top corners of a rectangle
Sam Lantinga <slouken@libsdl.org>
parents: 2997
diff changeset
153 (y1 < recty1 && y2 < recty1) || (y1 > recty2 && y2 > recty2)) {
2909
3da0bb421d83 Added line clipping
Sam Lantinga <slouken@libsdl.org>
parents: 2859
diff changeset
154 return SDL_FALSE;
3da0bb421d83 Added line clipping
Sam Lantinga <slouken@libsdl.org>
parents: 2859
diff changeset
155 }
3da0bb421d83 Added line clipping
Sam Lantinga <slouken@libsdl.org>
parents: 2859
diff changeset
156
2994
7563b99e9a49 Date: Sat, 3 Jan 2009 22:11:18 -0500
Sam Lantinga <slouken@libsdl.org>
parents: 2920
diff changeset
157 if (y1 == y2) {
2909
3da0bb421d83 Added line clipping
Sam Lantinga <slouken@libsdl.org>
parents: 2859
diff changeset
158 /* Horizontal line, easy to clip */
3da0bb421d83 Added line clipping
Sam Lantinga <slouken@libsdl.org>
parents: 2859
diff changeset
159 if (x1 < rectx1) {
3da0bb421d83 Added line clipping
Sam Lantinga <slouken@libsdl.org>
parents: 2859
diff changeset
160 *X1 = rectx1;
3da0bb421d83 Added line clipping
Sam Lantinga <slouken@libsdl.org>
parents: 2859
diff changeset
161 } else if (x1 > rectx2) {
3da0bb421d83 Added line clipping
Sam Lantinga <slouken@libsdl.org>
parents: 2859
diff changeset
162 *X1 = rectx2;
3da0bb421d83 Added line clipping
Sam Lantinga <slouken@libsdl.org>
parents: 2859
diff changeset
163 }
3da0bb421d83 Added line clipping
Sam Lantinga <slouken@libsdl.org>
parents: 2859
diff changeset
164 if (x2 < rectx1) {
3da0bb421d83 Added line clipping
Sam Lantinga <slouken@libsdl.org>
parents: 2859
diff changeset
165 *X2 = rectx1;
3da0bb421d83 Added line clipping
Sam Lantinga <slouken@libsdl.org>
parents: 2859
diff changeset
166 } else if (x2 > rectx2) {
3da0bb421d83 Added line clipping
Sam Lantinga <slouken@libsdl.org>
parents: 2859
diff changeset
167 *X2 = rectx2;
3da0bb421d83 Added line clipping
Sam Lantinga <slouken@libsdl.org>
parents: 2859
diff changeset
168 }
3da0bb421d83 Added line clipping
Sam Lantinga <slouken@libsdl.org>
parents: 2859
diff changeset
169 return SDL_TRUE;
3da0bb421d83 Added line clipping
Sam Lantinga <slouken@libsdl.org>
parents: 2859
diff changeset
170 }
3da0bb421d83 Added line clipping
Sam Lantinga <slouken@libsdl.org>
parents: 2859
diff changeset
171
3da0bb421d83 Added line clipping
Sam Lantinga <slouken@libsdl.org>
parents: 2859
diff changeset
172 if (x1 == x2) {
3da0bb421d83 Added line clipping
Sam Lantinga <slouken@libsdl.org>
parents: 2859
diff changeset
173 /* Vertical line, easy to clip */
3da0bb421d83 Added line clipping
Sam Lantinga <slouken@libsdl.org>
parents: 2859
diff changeset
174 if (y1 < recty1) {
3da0bb421d83 Added line clipping
Sam Lantinga <slouken@libsdl.org>
parents: 2859
diff changeset
175 *Y1 = recty1;
3da0bb421d83 Added line clipping
Sam Lantinga <slouken@libsdl.org>
parents: 2859
diff changeset
176 } else if (y1 > recty2) {
3da0bb421d83 Added line clipping
Sam Lantinga <slouken@libsdl.org>
parents: 2859
diff changeset
177 *Y1 = recty2;
3da0bb421d83 Added line clipping
Sam Lantinga <slouken@libsdl.org>
parents: 2859
diff changeset
178 }
3da0bb421d83 Added line clipping
Sam Lantinga <slouken@libsdl.org>
parents: 2859
diff changeset
179 if (y2 < recty1) {
3da0bb421d83 Added line clipping
Sam Lantinga <slouken@libsdl.org>
parents: 2859
diff changeset
180 *Y2 = recty1;
3da0bb421d83 Added line clipping
Sam Lantinga <slouken@libsdl.org>
parents: 2859
diff changeset
181 } else if (y2 > recty2) {
3da0bb421d83 Added line clipping
Sam Lantinga <slouken@libsdl.org>
parents: 2859
diff changeset
182 *Y2 = recty2;
3da0bb421d83 Added line clipping
Sam Lantinga <slouken@libsdl.org>
parents: 2859
diff changeset
183 }
3da0bb421d83 Added line clipping
Sam Lantinga <slouken@libsdl.org>
parents: 2859
diff changeset
184 return SDL_TRUE;
3da0bb421d83 Added line clipping
Sam Lantinga <slouken@libsdl.org>
parents: 2859
diff changeset
185 }
3da0bb421d83 Added line clipping
Sam Lantinga <slouken@libsdl.org>
parents: 2859
diff changeset
186
2997
Sam Lantinga <slouken@libsdl.org>
parents: 2994
diff changeset
187 else {
Sam Lantinga <slouken@libsdl.org>
parents: 2994
diff changeset
188 /* The task of clipping a line with finite slope ratios in a fixed-
Sam Lantinga <slouken@libsdl.org>
parents: 2994
diff changeset
189 * precision coordinate space is not as immediately simple as it is
Sam Lantinga <slouken@libsdl.org>
parents: 2994
diff changeset
190 * with coordinates of arbitrary precision. If the ratio of slopes
Sam Lantinga <slouken@libsdl.org>
parents: 2994
diff changeset
191 * between the input line segment and the result line segment is not
Sam Lantinga <slouken@libsdl.org>
parents: 2994
diff changeset
192 * a whole number, you have in fact *moved* the line segment a bit,
Sam Lantinga <slouken@libsdl.org>
parents: 2994
diff changeset
193 * and there can be no avoiding it without more precision
Sam Lantinga <slouken@libsdl.org>
parents: 2994
diff changeset
194 */
Sam Lantinga <slouken@libsdl.org>
parents: 2994
diff changeset
195 int *x_result_[] = { X1, X2, NULL }, **x_result = x_result_;
Sam Lantinga <slouken@libsdl.org>
parents: 2994
diff changeset
196 int *y_result_[] = { Y1, Y2, NULL }, **y_result = y_result_;
2994
7563b99e9a49 Date: Sat, 3 Jan 2009 22:11:18 -0500
Sam Lantinga <slouken@libsdl.org>
parents: 2920
diff changeset
197 SDL_bool intersection = SDL_FALSE;
7563b99e9a49 Date: Sat, 3 Jan 2009 22:11:18 -0500
Sam Lantinga <slouken@libsdl.org>
parents: 2920
diff changeset
198 double b, m, left, right, bottom, top;
7563b99e9a49 Date: Sat, 3 Jan 2009 22:11:18 -0500
Sam Lantinga <slouken@libsdl.org>
parents: 2920
diff changeset
199 int xl, xh, yl, yh;
7563b99e9a49 Date: Sat, 3 Jan 2009 22:11:18 -0500
Sam Lantinga <slouken@libsdl.org>
parents: 2920
diff changeset
200
7563b99e9a49 Date: Sat, 3 Jan 2009 22:11:18 -0500
Sam Lantinga <slouken@libsdl.org>
parents: 2920
diff changeset
201 /* solve mx+b line formula */
2997
Sam Lantinga <slouken@libsdl.org>
parents: 2994
diff changeset
202 m = (double) (y1 - y2) / (double) (x1 - x2);
2994
7563b99e9a49 Date: Sat, 3 Jan 2009 22:11:18 -0500
Sam Lantinga <slouken@libsdl.org>
parents: 2920
diff changeset
203 b = y2 - m * (double) x2;
7563b99e9a49 Date: Sat, 3 Jan 2009 22:11:18 -0500
Sam Lantinga <slouken@libsdl.org>
parents: 2920
diff changeset
204
7563b99e9a49 Date: Sat, 3 Jan 2009 22:11:18 -0500
Sam Lantinga <slouken@libsdl.org>
parents: 2920
diff changeset
205 /* find some linear intersections */
7563b99e9a49 Date: Sat, 3 Jan 2009 22:11:18 -0500
Sam Lantinga <slouken@libsdl.org>
parents: 2920
diff changeset
206 left = (m * (double) rectx1) + b;
7563b99e9a49 Date: Sat, 3 Jan 2009 22:11:18 -0500
Sam Lantinga <slouken@libsdl.org>
parents: 2920
diff changeset
207 right = (m * (double) rectx2) + b;
7563b99e9a49 Date: Sat, 3 Jan 2009 22:11:18 -0500
Sam Lantinga <slouken@libsdl.org>
parents: 2920
diff changeset
208 top = (recty1 - b) / m;
7563b99e9a49 Date: Sat, 3 Jan 2009 22:11:18 -0500
Sam Lantinga <slouken@libsdl.org>
parents: 2920
diff changeset
209 bottom = (recty2 - b) / m;
7563b99e9a49 Date: Sat, 3 Jan 2009 22:11:18 -0500
Sam Lantinga <slouken@libsdl.org>
parents: 2920
diff changeset
210
7563b99e9a49 Date: Sat, 3 Jan 2009 22:11:18 -0500
Sam Lantinga <slouken@libsdl.org>
parents: 2920
diff changeset
211 /* sort end-points' x and y components individually */
7563b99e9a49 Date: Sat, 3 Jan 2009 22:11:18 -0500
Sam Lantinga <slouken@libsdl.org>
parents: 2920
diff changeset
212 if (x1 < x2) {
7563b99e9a49 Date: Sat, 3 Jan 2009 22:11:18 -0500
Sam Lantinga <slouken@libsdl.org>
parents: 2920
diff changeset
213 xl = x1;
7563b99e9a49 Date: Sat, 3 Jan 2009 22:11:18 -0500
Sam Lantinga <slouken@libsdl.org>
parents: 2920
diff changeset
214 xh = x2;
7563b99e9a49 Date: Sat, 3 Jan 2009 22:11:18 -0500
Sam Lantinga <slouken@libsdl.org>
parents: 2920
diff changeset
215 } else {
7563b99e9a49 Date: Sat, 3 Jan 2009 22:11:18 -0500
Sam Lantinga <slouken@libsdl.org>
parents: 2920
diff changeset
216 xl = x2;
7563b99e9a49 Date: Sat, 3 Jan 2009 22:11:18 -0500
Sam Lantinga <slouken@libsdl.org>
parents: 2920
diff changeset
217 xh = x1;
7563b99e9a49 Date: Sat, 3 Jan 2009 22:11:18 -0500
Sam Lantinga <slouken@libsdl.org>
parents: 2920
diff changeset
218 }
7563b99e9a49 Date: Sat, 3 Jan 2009 22:11:18 -0500
Sam Lantinga <slouken@libsdl.org>
parents: 2920
diff changeset
219 if (y1 < y2) {
7563b99e9a49 Date: Sat, 3 Jan 2009 22:11:18 -0500
Sam Lantinga <slouken@libsdl.org>
parents: 2920
diff changeset
220 yl = y1;
7563b99e9a49 Date: Sat, 3 Jan 2009 22:11:18 -0500
Sam Lantinga <slouken@libsdl.org>
parents: 2920
diff changeset
221 yh = y2;
7563b99e9a49 Date: Sat, 3 Jan 2009 22:11:18 -0500
Sam Lantinga <slouken@libsdl.org>
parents: 2920
diff changeset
222 } else {
7563b99e9a49 Date: Sat, 3 Jan 2009 22:11:18 -0500
Sam Lantinga <slouken@libsdl.org>
parents: 2920
diff changeset
223 yl = y2;
7563b99e9a49 Date: Sat, 3 Jan 2009 22:11:18 -0500
Sam Lantinga <slouken@libsdl.org>
parents: 2920
diff changeset
224 yh = y1;
7563b99e9a49 Date: Sat, 3 Jan 2009 22:11:18 -0500
Sam Lantinga <slouken@libsdl.org>
parents: 2920
diff changeset
225 }
7563b99e9a49 Date: Sat, 3 Jan 2009 22:11:18 -0500
Sam Lantinga <slouken@libsdl.org>
parents: 2920
diff changeset
226
7563b99e9a49 Date: Sat, 3 Jan 2009 22:11:18 -0500
Sam Lantinga <slouken@libsdl.org>
parents: 2920
diff changeset
227 #define RISING(a, b, c) (((a)<=(b))&&((b)<=(c)))
7563b99e9a49 Date: Sat, 3 Jan 2009 22:11:18 -0500
Sam Lantinga <slouken@libsdl.org>
parents: 2920
diff changeset
228
7563b99e9a49 Date: Sat, 3 Jan 2009 22:11:18 -0500
Sam Lantinga <slouken@libsdl.org>
parents: 2920
diff changeset
229 /* check for a point that's entirely inside the rect */
7563b99e9a49 Date: Sat, 3 Jan 2009 22:11:18 -0500
Sam Lantinga <slouken@libsdl.org>
parents: 2920
diff changeset
230 if (RISING(rectx1, x1, rectx2) && RISING(recty1, y1, recty2)) {
7563b99e9a49 Date: Sat, 3 Jan 2009 22:11:18 -0500
Sam Lantinga <slouken@libsdl.org>
parents: 2920
diff changeset
231 x_result++;
7563b99e9a49 Date: Sat, 3 Jan 2009 22:11:18 -0500
Sam Lantinga <slouken@libsdl.org>
parents: 2920
diff changeset
232 y_result++;
7563b99e9a49 Date: Sat, 3 Jan 2009 22:11:18 -0500
Sam Lantinga <slouken@libsdl.org>
parents: 2920
diff changeset
233 intersection = SDL_TRUE;
2997
Sam Lantinga <slouken@libsdl.org>
parents: 2994
diff changeset
234 } else
Sam Lantinga <slouken@libsdl.org>
parents: 2994
diff changeset
235 /* it was determined earlier that *both* end-points are not contained */
2994
7563b99e9a49 Date: Sat, 3 Jan 2009 22:11:18 -0500
Sam Lantinga <slouken@libsdl.org>
parents: 2920
diff changeset
236 if (RISING(rectx1, x2, rectx2) && RISING(recty1, y2, recty2)) {
7563b99e9a49 Date: Sat, 3 Jan 2009 22:11:18 -0500
Sam Lantinga <slouken@libsdl.org>
parents: 2920
diff changeset
237 **(x_result++) = x2;
7563b99e9a49 Date: Sat, 3 Jan 2009 22:11:18 -0500
Sam Lantinga <slouken@libsdl.org>
parents: 2920
diff changeset
238 **(y_result++) = y2;
7563b99e9a49 Date: Sat, 3 Jan 2009 22:11:18 -0500
Sam Lantinga <slouken@libsdl.org>
parents: 2920
diff changeset
239 intersection = SDL_TRUE;
7563b99e9a49 Date: Sat, 3 Jan 2009 22:11:18 -0500
Sam Lantinga <slouken@libsdl.org>
parents: 2920
diff changeset
240 }
7563b99e9a49 Date: Sat, 3 Jan 2009 22:11:18 -0500
Sam Lantinga <slouken@libsdl.org>
parents: 2920
diff changeset
241
7563b99e9a49 Date: Sat, 3 Jan 2009 22:11:18 -0500
Sam Lantinga <slouken@libsdl.org>
parents: 2920
diff changeset
242 if (RISING(recty1, left, recty2) && RISING(xl, rectx1, xh)) {
7563b99e9a49 Date: Sat, 3 Jan 2009 22:11:18 -0500
Sam Lantinga <slouken@libsdl.org>
parents: 2920
diff changeset
243 **(x_result++) = rectx1;
7563b99e9a49 Date: Sat, 3 Jan 2009 22:11:18 -0500
Sam Lantinga <slouken@libsdl.org>
parents: 2920
diff changeset
244 **(y_result++) = (int) left;
7563b99e9a49 Date: Sat, 3 Jan 2009 22:11:18 -0500
Sam Lantinga <slouken@libsdl.org>
parents: 2920
diff changeset
245 intersection = SDL_TRUE;
7563b99e9a49 Date: Sat, 3 Jan 2009 22:11:18 -0500
Sam Lantinga <slouken@libsdl.org>
parents: 2920
diff changeset
246 }
7563b99e9a49 Date: Sat, 3 Jan 2009 22:11:18 -0500
Sam Lantinga <slouken@libsdl.org>
parents: 2920
diff changeset
247
2997
Sam Lantinga <slouken@libsdl.org>
parents: 2994
diff changeset
248 if (*x_result == NULL)
Sam Lantinga <slouken@libsdl.org>
parents: 2994
diff changeset
249 return intersection;
2994
7563b99e9a49 Date: Sat, 3 Jan 2009 22:11:18 -0500
Sam Lantinga <slouken@libsdl.org>
parents: 2920
diff changeset
250 if (RISING(recty1, right, recty2) && RISING(xl, rectx2, xh)) {
7563b99e9a49 Date: Sat, 3 Jan 2009 22:11:18 -0500
Sam Lantinga <slouken@libsdl.org>
parents: 2920
diff changeset
251 **(x_result++) = rectx2;
7563b99e9a49 Date: Sat, 3 Jan 2009 22:11:18 -0500
Sam Lantinga <slouken@libsdl.org>
parents: 2920
diff changeset
252 **(y_result++) = (int) right;
7563b99e9a49 Date: Sat, 3 Jan 2009 22:11:18 -0500
Sam Lantinga <slouken@libsdl.org>
parents: 2920
diff changeset
253 intersection = SDL_TRUE;
7563b99e9a49 Date: Sat, 3 Jan 2009 22:11:18 -0500
Sam Lantinga <slouken@libsdl.org>
parents: 2920
diff changeset
254 }
7563b99e9a49 Date: Sat, 3 Jan 2009 22:11:18 -0500
Sam Lantinga <slouken@libsdl.org>
parents: 2920
diff changeset
255
2997
Sam Lantinga <slouken@libsdl.org>
parents: 2994
diff changeset
256 if (*x_result == NULL)
Sam Lantinga <slouken@libsdl.org>
parents: 2994
diff changeset
257 return intersection;
2994
7563b99e9a49 Date: Sat, 3 Jan 2009 22:11:18 -0500
Sam Lantinga <slouken@libsdl.org>
parents: 2920
diff changeset
258 if (RISING(rectx1, top, rectx2) && RISING(yl, recty1, yh)) {
7563b99e9a49 Date: Sat, 3 Jan 2009 22:11:18 -0500
Sam Lantinga <slouken@libsdl.org>
parents: 2920
diff changeset
259 **(x_result++) = (int) top;
7563b99e9a49 Date: Sat, 3 Jan 2009 22:11:18 -0500
Sam Lantinga <slouken@libsdl.org>
parents: 2920
diff changeset
260 **(y_result++) = recty1;
7563b99e9a49 Date: Sat, 3 Jan 2009 22:11:18 -0500
Sam Lantinga <slouken@libsdl.org>
parents: 2920
diff changeset
261 intersection = SDL_TRUE;
7563b99e9a49 Date: Sat, 3 Jan 2009 22:11:18 -0500
Sam Lantinga <slouken@libsdl.org>
parents: 2920
diff changeset
262 }
7563b99e9a49 Date: Sat, 3 Jan 2009 22:11:18 -0500
Sam Lantinga <slouken@libsdl.org>
parents: 2920
diff changeset
263
2997
Sam Lantinga <slouken@libsdl.org>
parents: 2994
diff changeset
264 if (*x_result == NULL)
Sam Lantinga <slouken@libsdl.org>
parents: 2994
diff changeset
265 return intersection;
2994
7563b99e9a49 Date: Sat, 3 Jan 2009 22:11:18 -0500
Sam Lantinga <slouken@libsdl.org>
parents: 2920
diff changeset
266 if (RISING(rectx1, bottom, rectx2) && RISING(yl, recty2, yh)) {
7563b99e9a49 Date: Sat, 3 Jan 2009 22:11:18 -0500
Sam Lantinga <slouken@libsdl.org>
parents: 2920
diff changeset
267 **(x_result++) = (int) bottom;
7563b99e9a49 Date: Sat, 3 Jan 2009 22:11:18 -0500
Sam Lantinga <slouken@libsdl.org>
parents: 2920
diff changeset
268 **(y_result++) = recty2;
7563b99e9a49 Date: Sat, 3 Jan 2009 22:11:18 -0500
Sam Lantinga <slouken@libsdl.org>
parents: 2920
diff changeset
269 intersection = SDL_TRUE;
7563b99e9a49 Date: Sat, 3 Jan 2009 22:11:18 -0500
Sam Lantinga <slouken@libsdl.org>
parents: 2920
diff changeset
270 }
7563b99e9a49 Date: Sat, 3 Jan 2009 22:11:18 -0500
Sam Lantinga <slouken@libsdl.org>
parents: 2920
diff changeset
271
7563b99e9a49 Date: Sat, 3 Jan 2009 22:11:18 -0500
Sam Lantinga <slouken@libsdl.org>
parents: 2920
diff changeset
272 return intersection;
7563b99e9a49 Date: Sat, 3 Jan 2009 22:11:18 -0500
Sam Lantinga <slouken@libsdl.org>
parents: 2920
diff changeset
273 }
7563b99e9a49 Date: Sat, 3 Jan 2009 22:11:18 -0500
Sam Lantinga <slouken@libsdl.org>
parents: 2920
diff changeset
274
2909
3da0bb421d83 Added line clipping
Sam Lantinga <slouken@libsdl.org>
parents: 2859
diff changeset
275 return SDL_FALSE;
3da0bb421d83 Added line clipping
Sam Lantinga <slouken@libsdl.org>
parents: 2859
diff changeset
276 }
3da0bb421d83 Added line clipping
Sam Lantinga <slouken@libsdl.org>
parents: 2859
diff changeset
277
1895
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
278 void
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
279 SDL_AddDirtyRect(SDL_DirtyRectList * list, const SDL_Rect * rect)
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
280 {
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
281 SDL_DirtyRect *dirty;
2223
175754591a13 Optimized dirty rect code
Sam Lantinga <slouken@libsdl.org>
parents: 1895
diff changeset
282
175754591a13 Optimized dirty rect code
Sam Lantinga <slouken@libsdl.org>
parents: 1895
diff changeset
283 /* FIXME: At what point is this optimization too expensive? */
175754591a13 Optimized dirty rect code
Sam Lantinga <slouken@libsdl.org>
parents: 1895
diff changeset
284 for (dirty = list->list; dirty; dirty = dirty->next) {
175754591a13 Optimized dirty rect code
Sam Lantinga <slouken@libsdl.org>
parents: 1895
diff changeset
285 if (SDL_HasIntersection(&dirty->rect, rect)) {
175754591a13 Optimized dirty rect code
Sam Lantinga <slouken@libsdl.org>
parents: 1895
diff changeset
286 SDL_UnionRect(&dirty->rect, rect, &dirty->rect);
175754591a13 Optimized dirty rect code
Sam Lantinga <slouken@libsdl.org>
parents: 1895
diff changeset
287 return;
175754591a13 Optimized dirty rect code
Sam Lantinga <slouken@libsdl.org>
parents: 1895
diff changeset
288 }
175754591a13 Optimized dirty rect code
Sam Lantinga <slouken@libsdl.org>
parents: 1895
diff changeset
289 }
1895
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
290
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
291 if (list->free) {
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
292 dirty = list->free;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
293 list->free = dirty->next;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
294 } else {
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
295 dirty = (SDL_DirtyRect *) SDL_malloc(sizeof(*dirty));
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
296 if (!dirty) {
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
297 return;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
298 }
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
299 }
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
300 dirty->rect = *rect;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
301 dirty->next = list->list;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
302 list->list = dirty;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
303 }
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
304
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
305 void
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
306 SDL_ClearDirtyRects(SDL_DirtyRectList * list)
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
307 {
2224
29cc9e9c76bd Whoops, it's not quite that easy - fixed bug in SDL_ClearDirtyRects()
Sam Lantinga <slouken@libsdl.org>
parents: 2223
diff changeset
308 SDL_DirtyRect *prev, *curr;
29cc9e9c76bd Whoops, it's not quite that easy - fixed bug in SDL_ClearDirtyRects()
Sam Lantinga <slouken@libsdl.org>
parents: 2223
diff changeset
309
29cc9e9c76bd Whoops, it's not quite that easy - fixed bug in SDL_ClearDirtyRects()
Sam Lantinga <slouken@libsdl.org>
parents: 2223
diff changeset
310 /* Skip to the end of the free list */
29cc9e9c76bd Whoops, it's not quite that easy - fixed bug in SDL_ClearDirtyRects()
Sam Lantinga <slouken@libsdl.org>
parents: 2223
diff changeset
311 prev = NULL;
29cc9e9c76bd Whoops, it's not quite that easy - fixed bug in SDL_ClearDirtyRects()
Sam Lantinga <slouken@libsdl.org>
parents: 2223
diff changeset
312 for (curr = list->free; curr; curr = curr->next) {
29cc9e9c76bd Whoops, it's not quite that easy - fixed bug in SDL_ClearDirtyRects()
Sam Lantinga <slouken@libsdl.org>
parents: 2223
diff changeset
313 prev = curr;
29cc9e9c76bd Whoops, it's not quite that easy - fixed bug in SDL_ClearDirtyRects()
Sam Lantinga <slouken@libsdl.org>
parents: 2223
diff changeset
314 }
29cc9e9c76bd Whoops, it's not quite that easy - fixed bug in SDL_ClearDirtyRects()
Sam Lantinga <slouken@libsdl.org>
parents: 2223
diff changeset
315
29cc9e9c76bd Whoops, it's not quite that easy - fixed bug in SDL_ClearDirtyRects()
Sam Lantinga <slouken@libsdl.org>
parents: 2223
diff changeset
316 /* Add the list entries to the end */
29cc9e9c76bd Whoops, it's not quite that easy - fixed bug in SDL_ClearDirtyRects()
Sam Lantinga <slouken@libsdl.org>
parents: 2223
diff changeset
317 if (prev) {
29cc9e9c76bd Whoops, it's not quite that easy - fixed bug in SDL_ClearDirtyRects()
Sam Lantinga <slouken@libsdl.org>
parents: 2223
diff changeset
318 prev->next = list->list;
29cc9e9c76bd Whoops, it's not quite that easy - fixed bug in SDL_ClearDirtyRects()
Sam Lantinga <slouken@libsdl.org>
parents: 2223
diff changeset
319 } else {
29cc9e9c76bd Whoops, it's not quite that easy - fixed bug in SDL_ClearDirtyRects()
Sam Lantinga <slouken@libsdl.org>
parents: 2223
diff changeset
320 list->free = list->list;
29cc9e9c76bd Whoops, it's not quite that easy - fixed bug in SDL_ClearDirtyRects()
Sam Lantinga <slouken@libsdl.org>
parents: 2223
diff changeset
321 }
2223
175754591a13 Optimized dirty rect code
Sam Lantinga <slouken@libsdl.org>
parents: 1895
diff changeset
322 list->list = NULL;
1895
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
323 }
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
324
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
325 void
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
326 SDL_FreeDirtyRects(SDL_DirtyRectList * list)
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
327 {
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
328 while (list->list) {
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
329 SDL_DirtyRect *elem = list->list;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
330 list->list = elem->next;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
331 SDL_free(elem);
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
332 }
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
333 while (list->free) {
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
334 SDL_DirtyRect *elem = list->free;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
335 list->free = elem->next;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
336 SDL_free(elem);
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
337 }
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
338 }
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
339
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head.
Sam Lantinga <slouken@libsdl.org>
parents:
diff changeset
340 /* vi: set ts=4 sw=4 expandtab: */