xref: /linux/drivers/gpu/drm/drm_rect.c (revision db6d8d5fdf9537641c76ba7f32e02b4bcc600972)
1 /*
2  * Copyright (C) 2011-2013 Intel Corporation
3  *
4  * Permission is hereby granted, free of charge, to any person obtaining a
5  * copy of this software and associated documentation files (the "Software"),
6  * to deal in the Software without restriction, including without limitation
7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8  * and/or sell copies of the Software, and to permit persons to whom the
9  * Software is furnished to do so, subject to the following conditions:
10  *
11  * The above copyright notice and this permission notice (including the next
12  * paragraph) shall be included in all copies or substantial portions of the
13  * Software.
14  *
15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
18  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
20  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
21  * SOFTWARE.
22  */
23 
24 #include <linux/errno.h>
25 #include <linux/export.h>
26 #include <linux/kernel.h>
27 #include <drm/drmP.h>
28 #include <drm/drm_rect.h>
29 
30 /**
31  * drm_rect_intersect - intersect two rectangles
32  * @r1: first rectangle
33  * @r2: second rectangle
34  *
35  * Calculate the intersection of rectangles @r1 and @r2.
36  * @r1 will be overwritten with the intersection.
37  *
38  * RETURNS:
39  * %true if rectangle @r1 is still visible after the operation,
40  * %false otherwise.
41  */
42 bool drm_rect_intersect(struct drm_rect *r1, const struct drm_rect *r2)
43 {
44 	r1->x1 = max(r1->x1, r2->x1);
45 	r1->y1 = max(r1->y1, r2->y1);
46 	r1->x2 = min(r1->x2, r2->x2);
47 	r1->y2 = min(r1->y2, r2->y2);
48 
49 	return drm_rect_visible(r1);
50 }
51 EXPORT_SYMBOL(drm_rect_intersect);
52 
53 /**
54  * drm_rect_clip_scaled - perform a scaled clip operation
55  * @src: source window rectangle
56  * @dst: destination window rectangle
57  * @clip: clip rectangle
58  * @hscale: horizontal scaling factor
59  * @vscale: vertical scaling factor
60  *
61  * Clip rectangle @dst by rectangle @clip. Clip rectangle @src by the
62  * same amounts multiplied by @hscale and @vscale.
63  *
64  * RETURNS:
65  * %true if rectangle @dst is still visible after being clipped,
66  * %false otherwise
67  */
68 bool drm_rect_clip_scaled(struct drm_rect *src, struct drm_rect *dst,
69 			  const struct drm_rect *clip,
70 			  int hscale, int vscale)
71 {
72 	int diff;
73 
74 	diff = clip->x1 - dst->x1;
75 	if (diff > 0) {
76 		int64_t tmp = src->x1 + (int64_t) diff * hscale;
77 		src->x1 = clamp_t(int64_t, tmp, INT_MIN, INT_MAX);
78 	}
79 	diff = clip->y1 - dst->y1;
80 	if (diff > 0) {
81 		int64_t tmp = src->y1 + (int64_t) diff * vscale;
82 		src->y1 = clamp_t(int64_t, tmp, INT_MIN, INT_MAX);
83 	}
84 	diff = dst->x2 - clip->x2;
85 	if (diff > 0) {
86 		int64_t tmp = src->x2 - (int64_t) diff * hscale;
87 		src->x2 = clamp_t(int64_t, tmp, INT_MIN, INT_MAX);
88 	}
89 	diff = dst->y2 - clip->y2;
90 	if (diff > 0) {
91 		int64_t tmp = src->y2 - (int64_t) diff * vscale;
92 		src->y2 = clamp_t(int64_t, tmp, INT_MIN, INT_MAX);
93 	}
94 
95 	return drm_rect_intersect(dst, clip);
96 }
97 EXPORT_SYMBOL(drm_rect_clip_scaled);
98 
99 static int drm_calc_scale(int src, int dst)
100 {
101 	int scale = 0;
102 
103 	if (WARN_ON(src < 0 || dst < 0))
104 		return -EINVAL;
105 
106 	if (dst == 0)
107 		return 0;
108 
109 	scale = src / dst;
110 
111 	return scale;
112 }
113 
114 /**
115  * drm_rect_calc_hscale - calculate the horizontal scaling factor
116  * @src: source window rectangle
117  * @dst: destination window rectangle
118  * @min_hscale: minimum allowed horizontal scaling factor
119  * @max_hscale: maximum allowed horizontal scaling factor
120  *
121  * Calculate the horizontal scaling factor as
122  * (@src width) / (@dst width).
123  *
124  * RETURNS:
125  * The horizontal scaling factor, or errno of out of limits.
126  */
127 int drm_rect_calc_hscale(const struct drm_rect *src,
128 			 const struct drm_rect *dst,
129 			 int min_hscale, int max_hscale)
130 {
131 	int src_w = drm_rect_width(src);
132 	int dst_w = drm_rect_width(dst);
133 	int hscale = drm_calc_scale(src_w, dst_w);
134 
135 	if (hscale < 0 || dst_w == 0)
136 		return hscale;
137 
138 	if (hscale < min_hscale || hscale > max_hscale)
139 		return -ERANGE;
140 
141 	return hscale;
142 }
143 EXPORT_SYMBOL(drm_rect_calc_hscale);
144 
145 /**
146  * drm_rect_calc_vscale - calculate the vertical scaling factor
147  * @src: source window rectangle
148  * @dst: destination window rectangle
149  * @min_vscale: minimum allowed vertical scaling factor
150  * @max_vscale: maximum allowed vertical scaling factor
151  *
152  * Calculate the vertical scaling factor as
153  * (@src height) / (@dst height).
154  *
155  * RETURNS:
156  * The vertical scaling factor, or errno of out of limits.
157  */
158 int drm_rect_calc_vscale(const struct drm_rect *src,
159 			 const struct drm_rect *dst,
160 			 int min_vscale, int max_vscale)
161 {
162 	int src_h = drm_rect_height(src);
163 	int dst_h = drm_rect_height(dst);
164 	int vscale = drm_calc_scale(src_h, dst_h);
165 
166 	if (vscale < 0 || dst_h == 0)
167 		return vscale;
168 
169 	if (vscale < min_vscale || vscale > max_vscale)
170 		return -ERANGE;
171 
172 	return vscale;
173 }
174 EXPORT_SYMBOL(drm_rect_calc_vscale);
175 
176 /**
177  * drm_calc_hscale_relaxed - calculate the horizontal scaling factor
178  * @src: source window rectangle
179  * @dst: destination window rectangle
180  * @min_hscale: minimum allowed horizontal scaling factor
181  * @max_hscale: maximum allowed horizontal scaling factor
182  *
183  * Calculate the horizontal scaling factor as
184  * (@src width) / (@dst width).
185  *
186  * If the calculated scaling factor is below @min_vscale,
187  * decrease the height of rectangle @dst to compensate.
188  *
189  * If the calculated scaling factor is above @max_vscale,
190  * decrease the height of rectangle @src to compensate.
191  *
192  * RETURNS:
193  * The horizontal scaling factor.
194  */
195 int drm_rect_calc_hscale_relaxed(struct drm_rect *src,
196 				 struct drm_rect *dst,
197 				 int min_hscale, int max_hscale)
198 {
199 	int src_w = drm_rect_width(src);
200 	int dst_w = drm_rect_width(dst);
201 	int hscale = drm_calc_scale(src_w, dst_w);
202 
203 	if (hscale < 0 || dst_w == 0)
204 		return hscale;
205 
206 	if (hscale < min_hscale) {
207 		int max_dst_w = src_w / min_hscale;
208 
209 		drm_rect_adjust_size(dst, max_dst_w - dst_w, 0);
210 
211 		return min_hscale;
212 	}
213 
214 	if (hscale > max_hscale) {
215 		int max_src_w = dst_w * max_hscale;
216 
217 		drm_rect_adjust_size(src, max_src_w - src_w, 0);
218 
219 		return max_hscale;
220 	}
221 
222 	return hscale;
223 }
224 EXPORT_SYMBOL(drm_rect_calc_hscale_relaxed);
225 
226 /**
227  * drm_rect_calc_vscale_relaxed - calculate the vertical scaling factor
228  * @src: source window rectangle
229  * @dst: destination window rectangle
230  * @min_vscale: minimum allowed vertical scaling factor
231  * @max_vscale: maximum allowed vertical scaling factor
232  *
233  * Calculate the vertical scaling factor as
234  * (@src height) / (@dst height).
235  *
236  * If the calculated scaling factor is below @min_vscale,
237  * decrease the height of rectangle @dst to compensate.
238  *
239  * If the calculated scaling factor is above @max_vscale,
240  * decrease the height of rectangle @src to compensate.
241  *
242  * RETURNS:
243  * The vertical scaling factor.
244  */
245 int drm_rect_calc_vscale_relaxed(struct drm_rect *src,
246 				 struct drm_rect *dst,
247 				 int min_vscale, int max_vscale)
248 {
249 	int src_h = drm_rect_height(src);
250 	int dst_h = drm_rect_height(dst);
251 	int vscale = drm_calc_scale(src_h, dst_h);
252 
253 	if (vscale < 0 || dst_h == 0)
254 		return vscale;
255 
256 	if (vscale < min_vscale) {
257 		int max_dst_h = src_h / min_vscale;
258 
259 		drm_rect_adjust_size(dst, 0, max_dst_h - dst_h);
260 
261 		return min_vscale;
262 	}
263 
264 	if (vscale > max_vscale) {
265 		int max_src_h = dst_h * max_vscale;
266 
267 		drm_rect_adjust_size(src, 0, max_src_h - src_h);
268 
269 		return max_vscale;
270 	}
271 
272 	return vscale;
273 }
274 EXPORT_SYMBOL(drm_rect_calc_vscale_relaxed);
275 
276 /**
277  * drm_rect_debug_print - print the rectangle information
278  * @prefix: prefix string
279  * @r: rectangle to print
280  * @fixed_point: rectangle is in 16.16 fixed point format
281  */
282 void drm_rect_debug_print(const char *prefix, const struct drm_rect *r, bool fixed_point)
283 {
284 	int w = drm_rect_width(r);
285 	int h = drm_rect_height(r);
286 
287 	if (fixed_point)
288 		DRM_DEBUG_KMS("%s%d.%06ux%d.%06u%+d.%06u%+d.%06u\n", prefix,
289 			      w >> 16, ((w & 0xffff) * 15625) >> 10,
290 			      h >> 16, ((h & 0xffff) * 15625) >> 10,
291 			      r->x1 >> 16, ((r->x1 & 0xffff) * 15625) >> 10,
292 			      r->y1 >> 16, ((r->y1 & 0xffff) * 15625) >> 10);
293 	else
294 		DRM_DEBUG_KMS("%s%dx%d%+d%+d\n", prefix, w, h, r->x1, r->y1);
295 }
296 EXPORT_SYMBOL(drm_rect_debug_print);
297 
298 /**
299  * drm_rect_rotate - Rotate the rectangle
300  * @r: rectangle to be rotated
301  * @width: Width of the coordinate space
302  * @height: Height of the coordinate space
303  * @rotation: Transformation to be applied
304  *
305  * Apply @rotation to the coordinates of rectangle @r.
306  *
307  * @width and @height combined with @rotation define
308  * the location of the new origin.
309  *
310  * @width correcsponds to the horizontal and @height
311  * to the vertical axis of the untransformed coordinate
312  * space.
313  */
314 void drm_rect_rotate(struct drm_rect *r,
315 		     int width, int height,
316 		     unsigned int rotation)
317 {
318 	struct drm_rect tmp;
319 
320 	if (rotation & (DRM_REFLECT_X | DRM_REFLECT_Y)) {
321 		tmp = *r;
322 
323 		if (rotation & DRM_REFLECT_X) {
324 			r->x1 = width - tmp.x2;
325 			r->x2 = width - tmp.x1;
326 		}
327 
328 		if (rotation & DRM_REFLECT_Y) {
329 			r->y1 = height - tmp.y2;
330 			r->y2 = height - tmp.y1;
331 		}
332 	}
333 
334 	switch (rotation & DRM_ROTATE_MASK) {
335 	case DRM_ROTATE_0:
336 		break;
337 	case DRM_ROTATE_90:
338 		tmp = *r;
339 		r->x1 = tmp.y1;
340 		r->x2 = tmp.y2;
341 		r->y1 = width - tmp.x2;
342 		r->y2 = width - tmp.x1;
343 		break;
344 	case DRM_ROTATE_180:
345 		tmp = *r;
346 		r->x1 = width - tmp.x2;
347 		r->x2 = width - tmp.x1;
348 		r->y1 = height - tmp.y2;
349 		r->y2 = height - tmp.y1;
350 		break;
351 	case DRM_ROTATE_270:
352 		tmp = *r;
353 		r->x1 = height - tmp.y2;
354 		r->x2 = height - tmp.y1;
355 		r->y1 = tmp.x1;
356 		r->y2 = tmp.x2;
357 		break;
358 	default:
359 		break;
360 	}
361 }
362 EXPORT_SYMBOL(drm_rect_rotate);
363 
364 /**
365  * drm_rect_rotate_inv - Inverse rotate the rectangle
366  * @r: rectangle to be rotated
367  * @width: Width of the coordinate space
368  * @height: Height of the coordinate space
369  * @rotation: Transformation whose inverse is to be applied
370  *
371  * Apply the inverse of @rotation to the coordinates
372  * of rectangle @r.
373  *
374  * @width and @height combined with @rotation define
375  * the location of the new origin.
376  *
377  * @width correcsponds to the horizontal and @height
378  * to the vertical axis of the original untransformed
379  * coordinate space, so that you never have to flip
380  * them when doing a rotatation and its inverse.
381  * That is, if you do:
382  *
383  * drm_rotate(&r, width, height, rotation);
384  * drm_rotate_inv(&r, width, height, rotation);
385  *
386  * you will always get back the original rectangle.
387  */
388 void drm_rect_rotate_inv(struct drm_rect *r,
389 			 int width, int height,
390 			 unsigned int rotation)
391 {
392 	struct drm_rect tmp;
393 
394 	switch (rotation & DRM_ROTATE_MASK) {
395 	case DRM_ROTATE_0:
396 		break;
397 	case DRM_ROTATE_90:
398 		tmp = *r;
399 		r->x1 = width - tmp.y2;
400 		r->x2 = width - tmp.y1;
401 		r->y1 = tmp.x1;
402 		r->y2 = tmp.x2;
403 		break;
404 	case DRM_ROTATE_180:
405 		tmp = *r;
406 		r->x1 = width - tmp.x2;
407 		r->x2 = width - tmp.x1;
408 		r->y1 = height - tmp.y2;
409 		r->y2 = height - tmp.y1;
410 		break;
411 	case DRM_ROTATE_270:
412 		tmp = *r;
413 		r->x1 = tmp.y1;
414 		r->x2 = tmp.y2;
415 		r->y1 = height - tmp.x2;
416 		r->y2 = height - tmp.x1;
417 		break;
418 	default:
419 		break;
420 	}
421 
422 	if (rotation & (DRM_REFLECT_X | DRM_REFLECT_Y)) {
423 		tmp = *r;
424 
425 		if (rotation & DRM_REFLECT_X) {
426 			r->x1 = width - tmp.x2;
427 			r->x2 = width - tmp.x1;
428 		}
429 
430 		if (rotation & DRM_REFLECT_Y) {
431 			r->y1 = height - tmp.y2;
432 			r->y2 = height - tmp.y1;
433 		}
434 	}
435 }
436 EXPORT_SYMBOL(drm_rect_rotate_inv);
437