1/*
2 Simple DirectMedia Layer
3 Copyright (C) 1997-2024 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
39extern "C" {
40#endif
41
42/**
43 * The structure that defines a point (integer)
44 *
45 * \sa SDL_EnclosePoints
46 * \sa SDL_PointInRect
47 */
48typedef 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_EncloseFPoints
58 * \sa SDL_PointInFRect
59 */
60typedef 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_IntersectRectAndLine
75 * \sa SDL_UnionRect
76 * \sa SDL_EnclosePoints
77 */
78typedef struct SDL_Rect
79{
80 int x, y;
81 int w, h;
82} SDL_Rect;
83
84
85/**
86 * A rectangle, with the origin at the upper left (floating point).
87 *
88 * \sa SDL_FRectEmpty
89 * \sa SDL_FRectEquals
90 * \sa SDL_FRectEqualsEpsilon
91 * \sa SDL_HasIntersectionF
92 * \sa SDL_IntersectFRect
93 * \sa SDL_IntersectFRectAndLine
94 * \sa SDL_UnionFRect
95 * \sa SDL_EncloseFPoints
96 * \sa SDL_PointInFRect
97 */
98typedef struct SDL_FRect
99{
100 float x;
101 float y;
102 float w;
103 float h;
104} SDL_FRect;
105
106
107/**
108 * Returns true if point resides inside a rectangle.
109 */
110SDL_FORCE_INLINE SDL_bool SDL_PointInRect(const SDL_Point *p, const SDL_Rect *r)
111{
112 return ( (p->x >= r->x) && (p->x < (r->x + r->w)) &&
113 (p->y >= r->y) && (p->y < (r->y + r->h)) ) ? SDL_TRUE : SDL_FALSE;
114}
115
116/**
117 * Returns true if the rectangle has no area.
118 */
119SDL_FORCE_INLINE SDL_bool SDL_RectEmpty(const SDL_Rect *r)
120{
121 return ((!r) || (r->w <= 0) || (r->h <= 0)) ? SDL_TRUE : SDL_FALSE;
122}
123
124/**
125 * Returns true if the two rectangles are equal.
126 */
127SDL_FORCE_INLINE SDL_bool SDL_RectEquals(const SDL_Rect *a, const SDL_Rect *b)
128{
129 return (a && b && (a->x == b->x) && (a->y == b->y) &&
130 (a->w == b->w) && (a->h == b->h)) ? SDL_TRUE : SDL_FALSE;
131}
132
133/**
134 * Determine whether two rectangles intersect.
135 *
136 * If either pointer is NULL the function will return SDL_FALSE.
137 *
138 * \param A an SDL_Rect structure representing the first rectangle
139 * \param B an SDL_Rect structure representing the second rectangle
140 * \returns SDL_TRUE if there is an intersection, SDL_FALSE otherwise.
141 *
142 * \since This function is available since SDL 2.0.0.
143 *
144 * \sa SDL_IntersectRect
145 */
146extern DECLSPEC SDL_bool SDLCALL SDL_HasIntersection(const SDL_Rect * A,
147 const SDL_Rect * B);
148
149/**
150 * Calculate the intersection of two rectangles.
151 *
152 * If `result` is NULL then this function will return SDL_FALSE.
153 *
154 * \param A an SDL_Rect structure representing the first rectangle
155 * \param B an SDL_Rect structure representing the second rectangle
156 * \param result an SDL_Rect structure filled in with the intersection of
157 * rectangles `A` and `B`
158 * \returns SDL_TRUE if there is an intersection, SDL_FALSE otherwise.
159 *
160 * \since This function is available since SDL 2.0.0.
161 *
162 * \sa SDL_HasIntersection
163 */
164extern DECLSPEC SDL_bool SDLCALL SDL_IntersectRect(const SDL_Rect * A,
165 const SDL_Rect * B,
166 SDL_Rect * result);
167
168/**
169 * Calculate the union of two rectangles.
170 *
171 * \param A an SDL_Rect structure representing the first rectangle
172 * \param B an SDL_Rect structure representing the second rectangle
173 * \param result an SDL_Rect structure filled in with the union of rectangles
174 * `A` and `B`
175 *
176 * \since This function is available since SDL 2.0.0.
177 */
178extern DECLSPEC void SDLCALL SDL_UnionRect(const SDL_Rect * A,
179 const SDL_Rect * B,
180 SDL_Rect * result);
181
182/**
183 * Calculate a minimal rectangle enclosing a set of points.
184 *
185 * If `clip` is not NULL then only points inside of the clipping rectangle are
186 * considered.
187 *
188 * \param points an array of SDL_Point structures representing points to be
189 * enclosed
190 * \param count the number of structures in the `points` array
191 * \param clip an SDL_Rect used for clipping or NULL to enclose all points
192 * \param result an SDL_Rect structure filled in with the minimal enclosing
193 * rectangle
194 * \returns SDL_TRUE if any points were enclosed or SDL_FALSE if all the
195 * points were outside of the clipping rectangle.
196 *
197 * \since This function is available since SDL 2.0.0.
198 */
199extern DECLSPEC SDL_bool SDLCALL SDL_EnclosePoints(const SDL_Point * points,
200 int count,
201 const SDL_Rect * clip,
202 SDL_Rect * result);
203
204/**
205 * Calculate the intersection of a rectangle and line segment.
206 *
207 * This function is used to clip a line segment to a rectangle. A line segment
208 * contained entirely within the rectangle or that does not intersect will
209 * remain unchanged. A line segment that crosses the rectangle at either or
210 * both ends will be clipped to the boundary of the rectangle and the new
211 * coordinates saved in `X1`, `Y1`, `X2`, and/or `Y2` as necessary.
212 *
213 * \param rect an SDL_Rect structure representing the rectangle to intersect
214 * \param X1 a pointer to the starting X-coordinate of the line
215 * \param Y1 a pointer to the starting Y-coordinate of the line
216 * \param X2 a pointer to the ending X-coordinate of the line
217 * \param Y2 a pointer to the ending Y-coordinate of the line
218 * \returns SDL_TRUE if there is an intersection, SDL_FALSE otherwise.
219 *
220 * \since This function is available since SDL 2.0.0.
221 */
222extern DECLSPEC SDL_bool SDLCALL SDL_IntersectRectAndLine(const SDL_Rect *
223 rect, int *X1,
224 int *Y1, int *X2,
225 int *Y2);
226
227
228/* SDL_FRect versions... */
229
230/**
231 * Returns true if point resides inside a rectangle.
232 */
233SDL_FORCE_INLINE SDL_bool SDL_PointInFRect(const SDL_FPoint *p, const SDL_FRect *r)
234{
235 return ( (p->x >= r->x) && (p->x < (r->x + r->w)) &&
236 (p->y >= r->y) && (p->y < (r->y + r->h)) ) ? SDL_TRUE : SDL_FALSE;
237}
238
239/**
240 * Returns true if the rectangle has no area.
241 */
242SDL_FORCE_INLINE SDL_bool SDL_FRectEmpty(const SDL_FRect *r)
243{
244 return ((!r) || (r->w <= 0.0f) || (r->h <= 0.0f)) ? SDL_TRUE : SDL_FALSE;
245}
246
247/**
248 * Returns true if the two rectangles are equal, within some given epsilon.
249 *
250 * \since This function is available since SDL 2.0.22.
251 */
252SDL_FORCE_INLINE SDL_bool SDL_FRectEqualsEpsilon(const SDL_FRect *a, const SDL_FRect *b, const float epsilon)
253{
254 return (a && b && ((a == b) ||
255 ((SDL_fabsf(x: a->x - b->x) <= epsilon) &&
256 (SDL_fabsf(x: a->y - b->y) <= epsilon) &&
257 (SDL_fabsf(x: a->w - b->w) <= epsilon) &&
258 (SDL_fabsf(x: a->h - b->h) <= epsilon))))
259 ? SDL_TRUE : SDL_FALSE;
260}
261
262/**
263 * Returns true if the two rectangles are equal, using a default epsilon.
264 *
265 * \since This function is available since SDL 2.0.22.
266 */
267SDL_FORCE_INLINE SDL_bool SDL_FRectEquals(const SDL_FRect *a, const SDL_FRect *b)
268{
269 return SDL_FRectEqualsEpsilon(a, b, SDL_FLT_EPSILON);
270}
271
272/**
273 * Determine whether two rectangles intersect with float precision.
274 *
275 * If either pointer is NULL the function will return SDL_FALSE.
276 *
277 * \param A an SDL_FRect structure representing the first rectangle
278 * \param B an SDL_FRect structure representing the second rectangle
279 * \returns SDL_TRUE if there is an intersection, SDL_FALSE otherwise.
280 *
281 * \since This function is available since SDL 2.0.22.
282 *
283 * \sa SDL_IntersectRect
284 */
285extern DECLSPEC SDL_bool SDLCALL SDL_HasIntersectionF(const SDL_FRect * A,
286 const SDL_FRect * B);
287
288/**
289 * Calculate the intersection of two rectangles with float precision.
290 *
291 * If `result` is NULL then this function will return SDL_FALSE.
292 *
293 * \param A an SDL_FRect structure representing the first rectangle
294 * \param B an SDL_FRect structure representing the second rectangle
295 * \param result an SDL_FRect structure filled in with the intersection of
296 * rectangles `A` and `B`
297 * \returns SDL_TRUE if there is an intersection, SDL_FALSE otherwise.
298 *
299 * \since This function is available since SDL 2.0.22.
300 *
301 * \sa SDL_HasIntersectionF
302 */
303extern DECLSPEC SDL_bool SDLCALL SDL_IntersectFRect(const SDL_FRect * A,
304 const SDL_FRect * B,
305 SDL_FRect * result);
306
307/**
308 * Calculate the union of two rectangles with float precision.
309 *
310 * \param A an SDL_FRect structure representing the first rectangle
311 * \param B an SDL_FRect structure representing the second rectangle
312 * \param result an SDL_FRect structure filled in with the union of rectangles
313 * `A` and `B`
314 *
315 * \since This function is available since SDL 2.0.22.
316 */
317extern DECLSPEC void SDLCALL SDL_UnionFRect(const SDL_FRect * A,
318 const SDL_FRect * B,
319 SDL_FRect * result);
320
321/**
322 * Calculate a minimal rectangle enclosing a set of points with float
323 * precision.
324 *
325 * If `clip` is not NULL then only points inside of the clipping rectangle are
326 * considered.
327 *
328 * \param points an array of SDL_FPoint structures representing points to be
329 * enclosed
330 * \param count the number of structures in the `points` array
331 * \param clip an SDL_FRect used for clipping or NULL to enclose all points
332 * \param result an SDL_FRect structure filled in with the minimal enclosing
333 * rectangle
334 * \returns SDL_TRUE if any points were enclosed or SDL_FALSE if all the
335 * points were outside of the clipping rectangle.
336 *
337 * \since This function is available since SDL 2.0.22.
338 */
339extern DECLSPEC SDL_bool SDLCALL SDL_EncloseFPoints(const SDL_FPoint * points,
340 int count,
341 const SDL_FRect * clip,
342 SDL_FRect * result);
343
344/**
345 * Calculate the intersection of a rectangle and line segment with float
346 * precision.
347 *
348 * This function is used to clip a line segment to a rectangle. A line segment
349 * contained entirely within the rectangle or that does not intersect will
350 * remain unchanged. A line segment that crosses the rectangle at either or
351 * both ends will be clipped to the boundary of the rectangle and the new
352 * coordinates saved in `X1`, `Y1`, `X2`, and/or `Y2` as necessary.
353 *
354 * \param rect an SDL_FRect structure representing the rectangle to intersect
355 * \param X1 a pointer to the starting X-coordinate of the line
356 * \param Y1 a pointer to the starting Y-coordinate of the line
357 * \param X2 a pointer to the ending X-coordinate of the line
358 * \param Y2 a pointer to the ending Y-coordinate of the line
359 * \returns SDL_TRUE if there is an intersection, SDL_FALSE otherwise.
360 *
361 * \since This function is available since SDL 2.0.22.
362 */
363extern DECLSPEC SDL_bool SDLCALL SDL_IntersectFRectAndLine(const SDL_FRect *
364 rect, float *X1,
365 float *Y1, float *X2,
366 float *Y2);
367
368/* Ends C function definitions when using C++ */
369#ifdef __cplusplus
370}
371#endif
372#include "close_code.h"
373
374#endif /* SDL_rect_h_ */
375
376/* vi: set ts=4 sw=4 expandtab: */
377