xref: /netbsd-src/sys/external/bsd/drm2/dist/drm/drm_rect.c (revision 82d56013d7b633d116a93943de88e08335357a7c)
1 /*	$NetBSD: drm_rect.c,v 1.2 2018/08/27 04:58:19 riastradh Exp $	*/
2 
3 /*
4  * Copyright (C) 2011-2013 Intel Corporation
5  *
6  * Permission is hereby granted, free of charge, to any person obtaining a
7  * copy of this software and associated documentation files (the "Software"),
8  * to deal in the Software without restriction, including without limitation
9  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
10  * and/or sell copies of the Software, and to permit persons to whom the
11  * Software is furnished to do so, subject to the following conditions:
12  *
13  * The above copyright notice and this permission notice (including the next
14  * paragraph) shall be included in all copies or substantial portions of the
15  * Software.
16  *
17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
18  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
19  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
20  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
21  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
22  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
23  * SOFTWARE.
24  */
25 
26 #include <sys/cdefs.h>
27 __KERNEL_RCSID(0, "$NetBSD: drm_rect.c,v 1.2 2018/08/27 04:58:19 riastradh Exp $");
28 
29 #include <linux/errno.h>
30 #include <linux/export.h>
31 #include <linux/kernel.h>
32 #include <drm/drmP.h>
33 #include <drm/drm_rect.h>
34 
35 /**
36  * drm_rect_intersect - intersect two rectangles
37  * @r1: first rectangle
38  * @r2: second rectangle
39  *
40  * Calculate the intersection of rectangles @r1 and @r2.
41  * @r1 will be overwritten with the intersection.
42  *
43  * RETURNS:
44  * %true if rectangle @r1 is still visible after the operation,
45  * %false otherwise.
46  */
47 bool drm_rect_intersect(struct drm_rect *r1, const struct drm_rect *r2)
48 {
49 	r1->x1 = max(r1->x1, r2->x1);
50 	r1->y1 = max(r1->y1, r2->y1);
51 	r1->x2 = min(r1->x2, r2->x2);
52 	r1->y2 = min(r1->y2, r2->y2);
53 
54 	return drm_rect_visible(r1);
55 }
56 EXPORT_SYMBOL(drm_rect_intersect);
57 
58 /**
59  * drm_rect_clip_scaled - perform a scaled clip operation
60  * @src: source window rectangle
61  * @dst: destination window rectangle
62  * @clip: clip rectangle
63  * @hscale: horizontal scaling factor
64  * @vscale: vertical scaling factor
65  *
66  * Clip rectangle @dst by rectangle @clip. Clip rectangle @src by the
67  * same amounts multiplied by @hscale and @vscale.
68  *
69  * RETURNS:
70  * %true if rectangle @dst is still visible after being clipped,
71  * %false otherwise
72  */
73 bool drm_rect_clip_scaled(struct drm_rect *src, struct drm_rect *dst,
74 			  const struct drm_rect *clip,
75 			  int hscale, int vscale)
76 {
77 	int diff;
78 
79 	diff = clip->x1 - dst->x1;
80 	if (diff > 0) {
81 		int64_t tmp = src->x1 + (int64_t) diff * hscale;
82 		src->x1 = clamp_t(int64_t, tmp, INT_MIN, INT_MAX);
83 	}
84 	diff = clip->y1 - dst->y1;
85 	if (diff > 0) {
86 		int64_t tmp = src->y1 + (int64_t) diff * vscale;
87 		src->y1 = clamp_t(int64_t, tmp, INT_MIN, INT_MAX);
88 	}
89 	diff = dst->x2 - clip->x2;
90 	if (diff > 0) {
91 		int64_t tmp = src->x2 - (int64_t) diff * hscale;
92 		src->x2 = clamp_t(int64_t, tmp, INT_MIN, INT_MAX);
93 	}
94 	diff = dst->y2 - clip->y2;
95 	if (diff > 0) {
96 		int64_t tmp = src->y2 - (int64_t) diff * vscale;
97 		src->y2 = clamp_t(int64_t, tmp, INT_MIN, INT_MAX);
98 	}
99 
100 	return drm_rect_intersect(dst, clip);
101 }
102 EXPORT_SYMBOL(drm_rect_clip_scaled);
103 
104 static int drm_calc_scale(int src, int dst)
105 {
106 	int scale = 0;
107 
108 	if (src < 0 || dst < 0)
109 		return -EINVAL;
110 
111 	if (dst == 0)
112 		return 0;
113 
114 	scale = src / dst;
115 
116 	return scale;
117 }
118 
119 /**
120  * drm_rect_calc_hscale - calculate the horizontal scaling factor
121  * @src: source window rectangle
122  * @dst: destination window rectangle
123  * @min_hscale: minimum allowed horizontal scaling factor
124  * @max_hscale: maximum allowed horizontal scaling factor
125  *
126  * Calculate the horizontal scaling factor as
127  * (@src width) / (@dst width).
128  *
129  * RETURNS:
130  * The horizontal scaling factor, or errno of out of limits.
131  */
132 int drm_rect_calc_hscale(const struct drm_rect *src,
133 			 const struct drm_rect *dst,
134 			 int min_hscale, int max_hscale)
135 {
136 	int src_w = drm_rect_width(src);
137 	int dst_w = drm_rect_width(dst);
138 	int hscale = drm_calc_scale(src_w, dst_w);
139 
140 	if (hscale < 0 || dst_w == 0)
141 		return hscale;
142 
143 	if (hscale < min_hscale || hscale > max_hscale)
144 		return -ERANGE;
145 
146 	return hscale;
147 }
148 EXPORT_SYMBOL(drm_rect_calc_hscale);
149 
150 /**
151  * drm_rect_calc_vscale - calculate the vertical scaling factor
152  * @src: source window rectangle
153  * @dst: destination window rectangle
154  * @min_vscale: minimum allowed vertical scaling factor
155  * @max_vscale: maximum allowed vertical scaling factor
156  *
157  * Calculate the vertical scaling factor as
158  * (@src height) / (@dst height).
159  *
160  * RETURNS:
161  * The vertical scaling factor, or errno of out of limits.
162  */
163 int drm_rect_calc_vscale(const struct drm_rect *src,
164 			 const struct drm_rect *dst,
165 			 int min_vscale, int max_vscale)
166 {
167 	int src_h = drm_rect_height(src);
168 	int dst_h = drm_rect_height(dst);
169 	int vscale = drm_calc_scale(src_h, dst_h);
170 
171 	if (vscale < 0 || dst_h == 0)
172 		return vscale;
173 
174 	if (vscale < min_vscale || vscale > max_vscale)
175 		return -ERANGE;
176 
177 	return vscale;
178 }
179 EXPORT_SYMBOL(drm_rect_calc_vscale);
180 
181 /**
182  * drm_calc_hscale_relaxed - calculate the horizontal scaling factor
183  * @src: source window rectangle
184  * @dst: destination window rectangle
185  * @min_hscale: minimum allowed horizontal scaling factor
186  * @max_hscale: maximum allowed horizontal scaling factor
187  *
188  * Calculate the horizontal scaling factor as
189  * (@src width) / (@dst width).
190  *
191  * If the calculated scaling factor is below @min_vscale,
192  * decrease the height of rectangle @dst to compensate.
193  *
194  * If the calculated scaling factor is above @max_vscale,
195  * decrease the height of rectangle @src to compensate.
196  *
197  * RETURNS:
198  * The horizontal scaling factor.
199  */
200 int drm_rect_calc_hscale_relaxed(struct drm_rect *src,
201 				 struct drm_rect *dst,
202 				 int min_hscale, int max_hscale)
203 {
204 	int src_w = drm_rect_width(src);
205 	int dst_w = drm_rect_width(dst);
206 	int hscale = drm_calc_scale(src_w, dst_w);
207 
208 	if (hscale < 0 || dst_w == 0)
209 		return hscale;
210 
211 	if (hscale < min_hscale) {
212 		int max_dst_w = src_w / min_hscale;
213 
214 		drm_rect_adjust_size(dst, max_dst_w - dst_w, 0);
215 
216 		return min_hscale;
217 	}
218 
219 	if (hscale > max_hscale) {
220 		int max_src_w = dst_w * max_hscale;
221 
222 		drm_rect_adjust_size(src, max_src_w - src_w, 0);
223 
224 		return max_hscale;
225 	}
226 
227 	return hscale;
228 }
229 EXPORT_SYMBOL(drm_rect_calc_hscale_relaxed);
230 
231 /**
232  * drm_rect_calc_vscale_relaxed - calculate the vertical scaling factor
233  * @src: source window rectangle
234  * @dst: destination window rectangle
235  * @min_vscale: minimum allowed vertical scaling factor
236  * @max_vscale: maximum allowed vertical scaling factor
237  *
238  * Calculate the vertical scaling factor as
239  * (@src height) / (@dst height).
240  *
241  * If the calculated scaling factor is below @min_vscale,
242  * decrease the height of rectangle @dst to compensate.
243  *
244  * If the calculated scaling factor is above @max_vscale,
245  * decrease the height of rectangle @src to compensate.
246  *
247  * RETURNS:
248  * The vertical scaling factor.
249  */
250 int drm_rect_calc_vscale_relaxed(struct drm_rect *src,
251 				 struct drm_rect *dst,
252 				 int min_vscale, int max_vscale)
253 {
254 	int src_h = drm_rect_height(src);
255 	int dst_h = drm_rect_height(dst);
256 	int vscale = drm_calc_scale(src_h, dst_h);
257 
258 	if (vscale < 0 || dst_h == 0)
259 		return vscale;
260 
261 	if (vscale < min_vscale) {
262 		int max_dst_h = src_h / min_vscale;
263 
264 		drm_rect_adjust_size(dst, 0, max_dst_h - dst_h);
265 
266 		return min_vscale;
267 	}
268 
269 	if (vscale > max_vscale) {
270 		int max_src_h = dst_h * max_vscale;
271 
272 		drm_rect_adjust_size(src, 0, max_src_h - src_h);
273 
274 		return max_vscale;
275 	}
276 
277 	return vscale;
278 }
279 EXPORT_SYMBOL(drm_rect_calc_vscale_relaxed);
280 
281 /**
282  * drm_rect_debug_print - print the rectangle information
283  * @r: rectangle to print
284  * @fixed_point: rectangle is in 16.16 fixed point format
285  */
286 void drm_rect_debug_print(const struct drm_rect *r, bool fixed_point)
287 {
288 	int w = drm_rect_width(r);
289 	int h = drm_rect_height(r);
290 
291 	if (fixed_point)
292 		DRM_DEBUG_KMS("%d.%06ux%d.%06u%+d.%06u%+d.%06u\n",
293 			      w >> 16, ((w & 0xffff) * 15625) >> 10,
294 			      h >> 16, ((h & 0xffff) * 15625) >> 10,
295 			      r->x1 >> 16, ((r->x1 & 0xffff) * 15625) >> 10,
296 			      r->y1 >> 16, ((r->y1 & 0xffff) * 15625) >> 10);
297 	else
298 		DRM_DEBUG_KMS("%dx%d%+d%+d\n", w, h, r->x1, r->y1);
299 }
300 EXPORT_SYMBOL(drm_rect_debug_print);
301 
302 /**
303  * drm_rect_rotate - Rotate the rectangle
304  * @r: rectangle to be rotated
305  * @width: Width of the coordinate space
306  * @height: Height of the coordinate space
307  * @rotation: Transformation to be applied
308  *
309  * Apply @rotation to the coordinates of rectangle @r.
310  *
311  * @width and @height combined with @rotation define
312  * the location of the new origin.
313  *
314  * @width correcsponds to the horizontal and @height
315  * to the vertical axis of the untransformed coordinate
316  * space.
317  */
318 void drm_rect_rotate(struct drm_rect *r,
319 		     int width, int height,
320 		     unsigned int rotation)
321 {
322 	struct drm_rect tmp;
323 
324 	if (rotation & (BIT(DRM_REFLECT_X) | BIT(DRM_REFLECT_Y))) {
325 		tmp = *r;
326 
327 		if (rotation & BIT(DRM_REFLECT_X)) {
328 			r->x1 = width - tmp.x2;
329 			r->x2 = width - tmp.x1;
330 		}
331 
332 		if (rotation & BIT(DRM_REFLECT_Y)) {
333 			r->y1 = height - tmp.y2;
334 			r->y2 = height - tmp.y1;
335 		}
336 	}
337 
338 	switch (rotation & DRM_ROTATE_MASK) {
339 	case BIT(DRM_ROTATE_0):
340 		break;
341 	case BIT(DRM_ROTATE_90):
342 		tmp = *r;
343 		r->x1 = tmp.y1;
344 		r->x2 = tmp.y2;
345 		r->y1 = width - tmp.x2;
346 		r->y2 = width - tmp.x1;
347 		break;
348 	case BIT(DRM_ROTATE_180):
349 		tmp = *r;
350 		r->x1 = width - tmp.x2;
351 		r->x2 = width - tmp.x1;
352 		r->y1 = height - tmp.y2;
353 		r->y2 = height - tmp.y1;
354 		break;
355 	case BIT(DRM_ROTATE_270):
356 		tmp = *r;
357 		r->x1 = height - tmp.y2;
358 		r->x2 = height - tmp.y1;
359 		r->y1 = tmp.x1;
360 		r->y2 = tmp.x2;
361 		break;
362 	default:
363 		break;
364 	}
365 }
366 EXPORT_SYMBOL(drm_rect_rotate);
367 
368 /**
369  * drm_rect_rotate_inv - Inverse rotate the rectangle
370  * @r: rectangle to be rotated
371  * @width: Width of the coordinate space
372  * @height: Height of the coordinate space
373  * @rotation: Transformation whose inverse is to be applied
374  *
375  * Apply the inverse of @rotation to the coordinates
376  * of rectangle @r.
377  *
378  * @width and @height combined with @rotation define
379  * the location of the new origin.
380  *
381  * @width correcsponds to the horizontal and @height
382  * to the vertical axis of the original untransformed
383  * coordinate space, so that you never have to flip
384  * them when doing a rotatation and its inverse.
385  * That is, if you do:
386  *
387  * drm_rotate(&r, width, height, rotation);
388  * drm_rotate_inv(&r, width, height, rotation);
389  *
390  * you will always get back the original rectangle.
391  */
392 void drm_rect_rotate_inv(struct drm_rect *r,
393 			 int width, int height,
394 			 unsigned int rotation)
395 {
396 	struct drm_rect tmp;
397 
398 	switch (rotation & DRM_ROTATE_MASK) {
399 	case BIT(DRM_ROTATE_0):
400 		break;
401 	case BIT(DRM_ROTATE_90):
402 		tmp = *r;
403 		r->x1 = width - tmp.y2;
404 		r->x2 = width - tmp.y1;
405 		r->y1 = tmp.x1;
406 		r->y2 = tmp.x2;
407 		break;
408 	case BIT(DRM_ROTATE_180):
409 		tmp = *r;
410 		r->x1 = width - tmp.x2;
411 		r->x2 = width - tmp.x1;
412 		r->y1 = height - tmp.y2;
413 		r->y2 = height - tmp.y1;
414 		break;
415 	case BIT(DRM_ROTATE_270):
416 		tmp = *r;
417 		r->x1 = tmp.y1;
418 		r->x2 = tmp.y2;
419 		r->y1 = height - tmp.x2;
420 		r->y2 = height - tmp.x1;
421 		break;
422 	default:
423 		break;
424 	}
425 
426 	if (rotation & (BIT(DRM_REFLECT_X) | BIT(DRM_REFLECT_Y))) {
427 		tmp = *r;
428 
429 		if (rotation & BIT(DRM_REFLECT_X)) {
430 			r->x1 = width - tmp.x2;
431 			r->x2 = width - tmp.x1;
432 		}
433 
434 		if (rotation & BIT(DRM_REFLECT_Y)) {
435 			r->y1 = height - tmp.y2;
436 			r->y2 = height - tmp.y1;
437 		}
438 	}
439 }
440 EXPORT_SYMBOL(drm_rect_rotate_inv);
441