1 | /* |
2 | Simple DirectMedia Layer |
3 | Copyright (C) 1997-2021 Sam Lantinga <slouken@libsdl.org> |
4 | |
5 | This software is provided 'as-is', without any express or implied |
6 | warranty. In no event will the authors be held liable for any damages |
7 | arising from the use of this software. |
8 | |
9 | Permission is granted to anyone to use this software for any purpose, |
10 | including commercial applications, and to alter it and redistribute it |
11 | freely, subject to the following restrictions: |
12 | |
13 | 1. The origin of this software must not be misrepresented; you must not |
14 | claim that you wrote the original software. If you use this software |
15 | in a product, an acknowledgment in the product documentation would be |
16 | appreciated but is not required. |
17 | 2. Altered source versions must be plainly marked as such, and must not be |
18 | misrepresented as being the original software. |
19 | 3. This notice may not be removed or altered from any source distribution. |
20 | */ |
21 | |
22 | /** |
23 | * \file SDL_rect.h |
24 | * |
25 | * Header file for SDL_rect definition and management functions. |
26 | */ |
27 | |
28 | #ifndef SDL_rect_h_ |
29 | #define SDL_rect_h_ |
30 | |
31 | #include "SDL_stdinc.h" |
32 | #include "SDL_error.h" |
33 | #include "SDL_pixels.h" |
34 | #include "SDL_rwops.h" |
35 | |
36 | #include "begin_code.h" |
37 | /* Set up for C function definitions, even when using C++ */ |
38 | #ifdef __cplusplus |
39 | extern "C" { |
40 | #endif |
41 | |
42 | /** |
43 | * The structure that defines a point (integer) |
44 | * |
45 | * \sa SDL_EnclosePoints |
46 | * \sa SDL_PointInRect |
47 | */ |
48 | typedef struct SDL_Point |
49 | { |
50 | int x; |
51 | int y; |
52 | } SDL_Point; |
53 | |
54 | /** |
55 | * The structure that defines a point (floating point) |
56 | * |
57 | * \sa SDL_EnclosePoints |
58 | * \sa SDL_PointInRect |
59 | */ |
60 | typedef struct SDL_FPoint |
61 | { |
62 | float x; |
63 | float y; |
64 | } SDL_FPoint; |
65 | |
66 | |
67 | /** |
68 | * A rectangle, with the origin at the upper left (integer). |
69 | * |
70 | * \sa SDL_RectEmpty |
71 | * \sa SDL_RectEquals |
72 | * \sa SDL_HasIntersection |
73 | * \sa SDL_IntersectRect |
74 | * \sa SDL_UnionRect |
75 | * \sa SDL_EnclosePoints |
76 | */ |
77 | typedef struct SDL_Rect |
78 | { |
79 | int x, y; |
80 | int w, h; |
81 | } SDL_Rect; |
82 | |
83 | |
84 | /** |
85 | * A rectangle, with the origin at the upper left (floating point). |
86 | */ |
87 | typedef struct SDL_FRect |
88 | { |
89 | float x; |
90 | float y; |
91 | float w; |
92 | float h; |
93 | } SDL_FRect; |
94 | |
95 | |
96 | /** |
97 | * Returns true if point resides inside a rectangle. |
98 | */ |
99 | SDL_FORCE_INLINE SDL_bool SDL_PointInRect(const SDL_Point *p, const SDL_Rect *r) |
100 | { |
101 | return ( (p->x >= r->x) && (p->x < (r->x + r->w)) && |
102 | (p->y >= r->y) && (p->y < (r->y + r->h)) ) ? SDL_TRUE : SDL_FALSE; |
103 | } |
104 | |
105 | /** |
106 | * Returns true if the rectangle has no area. |
107 | */ |
108 | SDL_FORCE_INLINE SDL_bool SDL_RectEmpty(const SDL_Rect *r) |
109 | { |
110 | return ((!r) || (r->w <= 0) || (r->h <= 0)) ? SDL_TRUE : SDL_FALSE; |
111 | } |
112 | |
113 | /** |
114 | * Returns true if the two rectangles are equal. |
115 | */ |
116 | SDL_FORCE_INLINE SDL_bool SDL_RectEquals(const SDL_Rect *a, const SDL_Rect *b) |
117 | { |
118 | return (a && b && (a->x == b->x) && (a->y == b->y) && |
119 | (a->w == b->w) && (a->h == b->h)) ? SDL_TRUE : SDL_FALSE; |
120 | } |
121 | |
122 | /** |
123 | * Determine whether two rectangles intersect. |
124 | * |
125 | * If either pointer is NULL the function will return SDL_FALSE. |
126 | * |
127 | * \param A an SDL_Rect structure representing the first rectangle |
128 | * \param B an SDL_Rect structure representing the second rectangle |
129 | * \returns SDL_TRUE if there is an intersection, SDL_FALSE otherwise. |
130 | * |
131 | * \since This function is available since SDL 2.0.0. |
132 | * |
133 | * \sa SDL_IntersectRect |
134 | */ |
135 | extern DECLSPEC SDL_bool SDLCALL SDL_HasIntersection(const SDL_Rect * A, |
136 | const SDL_Rect * B); |
137 | |
138 | /** |
139 | * Calculate the intersection of two rectangles. |
140 | * |
141 | * If `result` is NULL then this function will return SDL_FALSE. |
142 | * |
143 | * \param A an SDL_Rect structure representing the first rectangle |
144 | * \param B an SDL_Rect structure representing the second rectangle |
145 | * \param result an SDL_Rect structure filled in with the intersection of |
146 | * rectangles `A` and `B` |
147 | * \returns SDL_TRUE if there is an intersection, SDL_FALSE otherwise. |
148 | * |
149 | * \since This function is available since SDL 2.0.0. |
150 | * |
151 | * \sa SDL_HasIntersection |
152 | */ |
153 | extern DECLSPEC SDL_bool SDLCALL SDL_IntersectRect(const SDL_Rect * A, |
154 | const SDL_Rect * B, |
155 | SDL_Rect * result); |
156 | |
157 | /** |
158 | * Calculate the union of two rectangles. |
159 | * |
160 | * \param A an SDL_Rect structure representing the first rectangle |
161 | * \param B an SDL_Rect structure representing the second rectangle |
162 | * \param result an SDL_Rect structure filled in with the union of rectangles |
163 | * `A` and `B` |
164 | */ |
165 | extern DECLSPEC void SDLCALL SDL_UnionRect(const SDL_Rect * A, |
166 | const SDL_Rect * B, |
167 | SDL_Rect * result); |
168 | |
169 | /** |
170 | * Calculate a minimal rectangle enclosing a set of points. |
171 | * |
172 | * If `clip` is not NULL then only points inside of the clipping rectangle |
173 | * are considered. |
174 | * |
175 | * \param points an array of SDL_Point structures representing points to be |
176 | * enclosed |
177 | * \param count the number of structures in the `points` array |
178 | * \param clip an SDL_Rect used for clipping or NULL to enclose all points |
179 | * \param result an SDL_Rect structure filled in with the minimal enclosing |
180 | * rectangle |
181 | * \returns SDL_TRUE if any points were enclosed or SDL_FALSE if all the |
182 | * points were outside of the clipping rectangle. |
183 | */ |
184 | extern DECLSPEC SDL_bool SDLCALL SDL_EnclosePoints(const SDL_Point * points, |
185 | int count, |
186 | const SDL_Rect * clip, |
187 | SDL_Rect * result); |
188 | |
189 | /** |
190 | * Calculate the intersection of a rectangle and line segment. |
191 | * |
192 | * This function is used to clip a line segment to a rectangle. A line segment |
193 | * contained entirely within the rectangle or that does not intersect will |
194 | * remain unchanged. A line segment that crosses the rectangle at either or |
195 | * both ends will be clipped to the boundary of the rectangle and the new |
196 | * coordinates saved in `X1`, `Y1`, `X2`, and/or `Y2` as necessary. |
197 | * |
198 | * \param rect an SDL_Rect structure representing the rectangle to intersect |
199 | * \param X1 a pointer to the starting X-coordinate of the line |
200 | * \param Y1 a pointer to the starting Y-coordinate of the line |
201 | * \param X2 a pointer to the ending X-coordinate of the line |
202 | * \param Y2 a pointer to the ending Y-coordinate of the line |
203 | * \returns SDL_TRUE if there is an intersection, SDL_FALSE otherwise. |
204 | */ |
205 | extern DECLSPEC SDL_bool SDLCALL SDL_IntersectRectAndLine(const SDL_Rect * |
206 | rect, int *X1, |
207 | int *Y1, int *X2, |
208 | int *Y2); |
209 | |
210 | /* Ends C function definitions when using C++ */ |
211 | #ifdef __cplusplus |
212 | } |
213 | #endif |
214 | #include "close_code.h" |
215 | |
216 | #endif /* SDL_rect_h_ */ |
217 | |
218 | /* vi: set ts=4 sw=4 expandtab: */ |
219 | |