xref: /openbsd-src/sys/dev/pci/drm/drm_rect.c (revision 0b7734b3d77bb9b21afec6f4621cae6c805dbd45)
1 /*	$OpenBSD: drm_rect.c,v 1.1 2015/09/23 23:12:11 kettenis Exp $	*/
2 /*
3  * Copyright (C) 2011-2013 Intel Corporation
4  *
5  * Permission is hereby granted, free of charge, to any person obtaining a
6  * copy of this software and associated documentation files (the "Software"),
7  * to deal in the Software without restriction, including without limitation
8  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
9  * and/or sell copies of the Software, and to permit persons to whom the
10  * Software is furnished to do so, subject to the following conditions:
11  *
12  * The above copyright notice and this permission notice (including the next
13  * paragraph) shall be included in all copies or substantial portions of the
14  * Software.
15  *
16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
22  * SOFTWARE.
23  */
24 
25 #include <dev/pci/drm/drmP.h>
26 #include <dev/pci/drm/drm_rect.h>
27 
28 /**
29  * drm_rect_intersect - intersect two rectangles
30  * @r1: first rectangle
31  * @r2: second rectangle
32  *
33  * Calculate the intersection of rectangles @r1 and @r2.
34  * @r1 will be overwritten with the intersection.
35  *
36  * RETURNS:
37  * %true if rectangle @r1 is still visible after the operation,
38  * %false otherwise.
39  */
40 bool drm_rect_intersect(struct drm_rect *r1, const struct drm_rect *r2)
41 {
42 	r1->x1 = max(r1->x1, r2->x1);
43 	r1->y1 = max(r1->y1, r2->y1);
44 	r1->x2 = min(r1->x2, r2->x2);
45 	r1->y2 = min(r1->y2, r2->y2);
46 
47 	return drm_rect_visible(r1);
48 }
49 EXPORT_SYMBOL(drm_rect_intersect);
50 
51 /**
52  * drm_rect_clip_scaled - perform a scaled clip operation
53  * @src: source window rectangle
54  * @dst: destination window rectangle
55  * @clip: clip rectangle
56  * @hscale: horizontal scaling factor
57  * @vscale: vertical scaling factor
58  *
59  * Clip rectangle @dst by rectangle @clip. Clip rectangle @src by the
60  * same amounts multiplied by @hscale and @vscale.
61  *
62  * RETURNS:
63  * %true if rectangle @dst is still visible after being clipped,
64  * %false otherwise
65  */
66 bool drm_rect_clip_scaled(struct drm_rect *src, struct drm_rect *dst,
67 			  const struct drm_rect *clip,
68 			  int hscale, int vscale)
69 {
70 	int diff;
71 
72 	diff = clip->x1 - dst->x1;
73 	if (diff > 0) {
74 		int64_t tmp = src->x1 + (int64_t) diff * hscale;
75 		src->x1 = clamp_t(int64_t, tmp, INT_MIN, INT_MAX);
76 	}
77 	diff = clip->y1 - dst->y1;
78 	if (diff > 0) {
79 		int64_t tmp = src->y1 + (int64_t) diff * vscale;
80 		src->y1 = clamp_t(int64_t, tmp, INT_MIN, INT_MAX);
81 	}
82 	diff = dst->x2 - clip->x2;
83 	if (diff > 0) {
84 		int64_t tmp = src->x2 - (int64_t) diff * hscale;
85 		src->x2 = clamp_t(int64_t, tmp, INT_MIN, INT_MAX);
86 	}
87 	diff = dst->y2 - clip->y2;
88 	if (diff > 0) {
89 		int64_t tmp = src->y2 - (int64_t) diff * vscale;
90 		src->y2 = clamp_t(int64_t, tmp, INT_MIN, INT_MAX);
91 	}
92 
93 	return drm_rect_intersect(dst, clip);
94 }
95 EXPORT_SYMBOL(drm_rect_clip_scaled);
96 
97 static int drm_calc_scale(int src, int dst)
98 {
99 	int scale = 0;
100 
101 	if (src < 0 || dst < 0)
102 		return -EINVAL;
103 
104 	if (dst == 0)
105 		return 0;
106 
107 	scale = src / dst;
108 
109 	return scale;
110 }
111 
112 /**
113  * drm_rect_calc_hscale - calculate the horizontal scaling factor
114  * @src: source window rectangle
115  * @dst: destination window rectangle
116  * @min_hscale: minimum allowed horizontal scaling factor
117  * @max_hscale: maximum allowed horizontal scaling factor
118  *
119  * Calculate the horizontal scaling factor as
120  * (@src width) / (@dst width).
121  *
122  * RETURNS:
123  * The horizontal scaling factor, or errno of out of limits.
124  */
125 int drm_rect_calc_hscale(const struct drm_rect *src,
126 			 const struct drm_rect *dst,
127 			 int min_hscale, int max_hscale)
128 {
129 	int src_w = drm_rect_width(src);
130 	int dst_w = drm_rect_width(dst);
131 	int hscale = drm_calc_scale(src_w, dst_w);
132 
133 	if (hscale < 0 || dst_w == 0)
134 		return hscale;
135 
136 	if (hscale < min_hscale || hscale > max_hscale)
137 		return -ERANGE;
138 
139 	return hscale;
140 }
141 EXPORT_SYMBOL(drm_rect_calc_hscale);
142 
143 /**
144  * drm_rect_calc_vscale - calculate the vertical scaling factor
145  * @src: source window rectangle
146  * @dst: destination window rectangle
147  * @min_vscale: minimum allowed vertical scaling factor
148  * @max_vscale: maximum allowed vertical scaling factor
149  *
150  * Calculate the vertical scaling factor as
151  * (@src height) / (@dst height).
152  *
153  * RETURNS:
154  * The vertical scaling factor, or errno of out of limits.
155  */
156 int drm_rect_calc_vscale(const struct drm_rect *src,
157 			 const struct drm_rect *dst,
158 			 int min_vscale, int max_vscale)
159 {
160 	int src_h = drm_rect_height(src);
161 	int dst_h = drm_rect_height(dst);
162 	int vscale = drm_calc_scale(src_h, dst_h);
163 
164 	if (vscale < 0 || dst_h == 0)
165 		return vscale;
166 
167 	if (vscale < min_vscale || vscale > max_vscale)
168 		return -ERANGE;
169 
170 	return vscale;
171 }
172 EXPORT_SYMBOL(drm_rect_calc_vscale);
173 
174 /**
175  * drm_calc_hscale_relaxed - calculate the horizontal scaling factor
176  * @src: source window rectangle
177  * @dst: destination window rectangle
178  * @min_hscale: minimum allowed horizontal scaling factor
179  * @max_hscale: maximum allowed horizontal scaling factor
180  *
181  * Calculate the horizontal scaling factor as
182  * (@src width) / (@dst width).
183  *
184  * If the calculated scaling factor is below @min_vscale,
185  * decrease the height of rectangle @dst to compensate.
186  *
187  * If the calculated scaling factor is above @max_vscale,
188  * decrease the height of rectangle @src to compensate.
189  *
190  * RETURNS:
191  * The horizontal scaling factor.
192  */
193 int drm_rect_calc_hscale_relaxed(struct drm_rect *src,
194 				 struct drm_rect *dst,
195 				 int min_hscale, int max_hscale)
196 {
197 	int src_w = drm_rect_width(src);
198 	int dst_w = drm_rect_width(dst);
199 	int hscale = drm_calc_scale(src_w, dst_w);
200 
201 	if (hscale < 0 || dst_w == 0)
202 		return hscale;
203 
204 	if (hscale < min_hscale) {
205 		int max_dst_w = src_w / min_hscale;
206 
207 		drm_rect_adjust_size(dst, max_dst_w - dst_w, 0);
208 
209 		return min_hscale;
210 	}
211 
212 	if (hscale > max_hscale) {
213 		int max_src_w = dst_w * max_hscale;
214 
215 		drm_rect_adjust_size(src, max_src_w - src_w, 0);
216 
217 		return max_hscale;
218 	}
219 
220 	return hscale;
221 }
222 EXPORT_SYMBOL(drm_rect_calc_hscale_relaxed);
223 
224 /**
225  * drm_rect_calc_vscale_relaxed - calculate the vertical scaling factor
226  * @src: source window rectangle
227  * @dst: destination window rectangle
228  * @min_vscale: minimum allowed vertical scaling factor
229  * @max_vscale: maximum allowed vertical scaling factor
230  *
231  * Calculate the vertical scaling factor as
232  * (@src height) / (@dst height).
233  *
234  * If the calculated scaling factor is below @min_vscale,
235  * decrease the height of rectangle @dst to compensate.
236  *
237  * If the calculated scaling factor is above @max_vscale,
238  * decrease the height of rectangle @src to compensate.
239  *
240  * RETURNS:
241  * The vertical scaling factor.
242  */
243 int drm_rect_calc_vscale_relaxed(struct drm_rect *src,
244 				 struct drm_rect *dst,
245 				 int min_vscale, int max_vscale)
246 {
247 	int src_h = drm_rect_height(src);
248 	int dst_h = drm_rect_height(dst);
249 	int vscale = drm_calc_scale(src_h, dst_h);
250 
251 	if (vscale < 0 || dst_h == 0)
252 		return vscale;
253 
254 	if (vscale < min_vscale) {
255 		int max_dst_h = src_h / min_vscale;
256 
257 		drm_rect_adjust_size(dst, 0, max_dst_h - dst_h);
258 
259 		return min_vscale;
260 	}
261 
262 	if (vscale > max_vscale) {
263 		int max_src_h = dst_h * max_vscale;
264 
265 		drm_rect_adjust_size(src, 0, max_src_h - src_h);
266 
267 		return max_vscale;
268 	}
269 
270 	return vscale;
271 }
272 EXPORT_SYMBOL(drm_rect_calc_vscale_relaxed);
273 
274 /**
275  * drm_rect_debug_print - print the rectangle information
276  * @r: rectangle to print
277  * @fixed_point: rectangle is in 16.16 fixed point format
278  */
279 void drm_rect_debug_print(const struct drm_rect *r, bool fixed_point)
280 {
281 #ifdef DRMDEBUG
282 	int w = drm_rect_width(r);
283 	int h = drm_rect_height(r);
284 #endif
285 
286 	if (fixed_point)
287 		DRM_DEBUG_KMS("%d.%06ux%d.%06u%+d.%06u%+d.%06u\n",
288 			      w >> 16, ((w & 0xffff) * 15625) >> 10,
289 			      h >> 16, ((h & 0xffff) * 15625) >> 10,
290 			      r->x1 >> 16, ((r->x1 & 0xffff) * 15625) >> 10,
291 			      r->y1 >> 16, ((r->y1 & 0xffff) * 15625) >> 10);
292 	else
293 		DRM_DEBUG_KMS("%dx%d%+d%+d\n", w, h, r->x1, r->y1);
294 }
295 EXPORT_SYMBOL(drm_rect_debug_print);
296