1/*
2 * Copyright © 2007 Keith Packard
3 *
4 * Permission to use, copy, modify, distribute, and sell this software and its
5 * documentation for any purpose is hereby granted without fee, provided that
6 * the above copyright notice appear in all copies and that both that copyright
7 * notice and this permission notice appear in supporting documentation, and
8 * that the name of the copyright holders not be used in advertising or
9 * publicity pertaining to distribution of the software without specific,
10 * written prior permission.  The copyright holders make no representations
11 * about the suitability of this software for any purpose.  It is provided "as
12 * is" without express or implied warranty.
13 *
14 * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
15 * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
16 * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
17 * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
18 * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
19 * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
20 * OF THIS SOFTWARE.
21 */
22
23#include "randrstr.h"
24#include "rrtransform.h"
25
26void
27RRTransformInit(RRTransformPtr transform)
28{
29    pixman_transform_init_identity(&transform->transform);
30    pixman_f_transform_init_identity(&transform->f_transform);
31    pixman_f_transform_init_identity(&transform->f_inverse);
32    transform->filter = NULL;
33    transform->params = NULL;
34    transform->nparams = 0;
35}
36
37void
38RRTransformFini(RRTransformPtr transform)
39{
40    free(transform->params);
41}
42
43Bool
44RRTransformEqual(RRTransformPtr a, RRTransformPtr b)
45{
46    if (a && pixman_transform_is_identity(&a->transform))
47        a = NULL;
48    if (b && pixman_transform_is_identity(&b->transform))
49        b = NULL;
50    if (a == NULL && b == NULL)
51        return TRUE;
52    if (a == NULL || b == NULL)
53        return FALSE;
54    if (memcmp(&a->transform, &b->transform, sizeof(a->transform)) != 0)
55        return FALSE;
56    if (a->filter != b->filter)
57        return FALSE;
58    if (a->nparams != b->nparams)
59        return FALSE;
60    if (memcmp(a->params, b->params, a->nparams * sizeof(xFixed)) != 0)
61        return FALSE;
62    return TRUE;
63}
64
65Bool
66RRTransformSetFilter(RRTransformPtr dst,
67                     PictFilterPtr filter,
68                     xFixed * params, int nparams, int width, int height)
69{
70    xFixed *new_params;
71
72    if (nparams) {
73        new_params = xallocarray(nparams, sizeof(xFixed));
74        if (!new_params)
75            return FALSE;
76        memcpy(new_params, params, nparams * sizeof(xFixed));
77    }
78    else
79        new_params = NULL;
80    free(dst->params);
81    dst->filter = filter;
82    dst->params = new_params;
83    dst->nparams = nparams;
84    dst->width = width;
85    dst->height = height;
86    return TRUE;
87}
88
89Bool
90RRTransformCopy(RRTransformPtr dst, RRTransformPtr src)
91{
92    if (src && pixman_transform_is_identity(&src->transform))
93        src = NULL;
94
95    if (src) {
96        if (!RRTransformSetFilter(dst, src->filter,
97                                  src->params, src->nparams, src->width,
98                                  src->height))
99            return FALSE;
100        dst->transform = src->transform;
101        dst->f_transform = src->f_transform;
102        dst->f_inverse = src->f_inverse;
103    }
104    else {
105        if (!RRTransformSetFilter(dst, NULL, NULL, 0, 0, 0))
106            return FALSE;
107        pixman_transform_init_identity(&dst->transform);
108        pixman_f_transform_init_identity(&dst->f_transform);
109        pixman_f_transform_init_identity(&dst->f_inverse);
110    }
111    return TRUE;
112}
113
114#define F(x)	IntToxFixed(x)
115
116static void
117RRTransformRescale(struct pixman_f_transform *f_transform, double limit)
118{
119    double max = 0, v, scale;
120    int i, j;
121
122    for (j = 0; j < 3; j++)
123        for (i = 0; i < 3; i++)
124            if ((v = fabs(f_transform->m[j][i])) > max)
125                max = v;
126    scale = limit / max;
127    for (j = 0; j < 3; j++)
128        for (i = 0; i < 3; i++)
129            f_transform->m[j][i] *= scale;
130}
131
132/*
133 * Compute the complete transformation matrix including
134 * client-specified transform, rotation/reflection values and the crtc
135 * offset.
136 *
137 * Return TRUE if the resulting transform is not a simple translation.
138 */
139Bool
140RRTransformCompute(int x,
141                   int y,
142                   int width,
143                   int height,
144                   Rotation rotation,
145                   RRTransformPtr rr_transform,
146                   PictTransformPtr transform,
147                   struct pixman_f_transform *f_transform,
148                   struct pixman_f_transform *f_inverse)
149{
150    PictTransform t_transform, inverse;
151    struct pixman_f_transform tf_transform, tf_inverse;
152    Bool overflow = FALSE;
153
154    if (!transform)
155        transform = &t_transform;
156    if (!f_transform)
157        f_transform = &tf_transform;
158    if (!f_inverse)
159        f_inverse = &tf_inverse;
160
161    pixman_transform_init_identity(transform);
162    pixman_transform_init_identity(&inverse);
163    pixman_f_transform_init_identity(f_transform);
164    pixman_f_transform_init_identity(f_inverse);
165    if (rotation != RR_Rotate_0) {
166        double f_rot_cos, f_rot_sin, f_rot_dx, f_rot_dy;
167        double f_scale_x, f_scale_y, f_scale_dx, f_scale_dy;
168        xFixed rot_cos, rot_sin, rot_dx, rot_dy;
169        xFixed scale_x, scale_y, scale_dx, scale_dy;
170
171        /* rotation */
172        switch (rotation & 0xf) {
173        default:
174        case RR_Rotate_0:
175            f_rot_cos = 1;
176            f_rot_sin = 0;
177            f_rot_dx = 0;
178            f_rot_dy = 0;
179            rot_cos = F(1);
180            rot_sin = F(0);
181            rot_dx = F(0);
182            rot_dy = F(0);
183            break;
184        case RR_Rotate_90:
185            f_rot_cos = 0;
186            f_rot_sin = 1;
187            f_rot_dx = height;
188            f_rot_dy = 0;
189            rot_cos = F(0);
190            rot_sin = F(1);
191            rot_dx = F(height);
192            rot_dy = F(0);
193            break;
194        case RR_Rotate_180:
195            f_rot_cos = -1;
196            f_rot_sin = 0;
197            f_rot_dx = width;
198            f_rot_dy = height;
199            rot_cos = F(~0u);
200            rot_sin = F(0);
201            rot_dx = F(width);
202            rot_dy = F(height);
203            break;
204        case RR_Rotate_270:
205            f_rot_cos = 0;
206            f_rot_sin = -1;
207            f_rot_dx = 0;
208            f_rot_dy = width;
209            rot_cos = F(0);
210            rot_sin = F(~0u);
211            rot_dx = F(0);
212            rot_dy = F(width);
213            break;
214        }
215
216        pixman_transform_rotate(transform, &inverse, rot_cos, rot_sin);
217        pixman_transform_translate(transform, &inverse, rot_dx, rot_dy);
218        pixman_f_transform_rotate(f_transform, f_inverse, f_rot_cos, f_rot_sin);
219        pixman_f_transform_translate(f_transform, f_inverse, f_rot_dx,
220                                     f_rot_dy);
221
222        /* reflection */
223        f_scale_x = 1;
224        f_scale_dx = 0;
225        f_scale_y = 1;
226        f_scale_dy = 0;
227        scale_x = F(1);
228        scale_dx = 0;
229        scale_y = F(1);
230        scale_dy = 0;
231        if (rotation & RR_Reflect_X) {
232            f_scale_x = -1;
233            scale_x = F(~0u);
234            if (rotation & (RR_Rotate_0 | RR_Rotate_180)) {
235                f_scale_dx = width;
236                scale_dx = F(width);
237            }
238            else {
239                f_scale_dx = height;
240                scale_dx = F(height);
241            }
242        }
243        if (rotation & RR_Reflect_Y) {
244            f_scale_y = -1;
245            scale_y = F(~0u);
246            if (rotation & (RR_Rotate_0 | RR_Rotate_180)) {
247                f_scale_dy = height;
248                scale_dy = F(height);
249            }
250            else {
251                f_scale_dy = width;
252                scale_dy = F(width);
253            }
254        }
255
256        pixman_transform_scale(transform, &inverse, scale_x, scale_y);
257        pixman_f_transform_scale(f_transform, f_inverse, f_scale_x, f_scale_y);
258        pixman_transform_translate(transform, &inverse, scale_dx, scale_dy);
259        pixman_f_transform_translate(f_transform, f_inverse, f_scale_dx,
260                                     f_scale_dy);
261    }
262
263#ifdef RANDR_12_INTERFACE
264    if (rr_transform) {
265        if (!pixman_transform_multiply
266            (transform, &rr_transform->transform, transform))
267            overflow = TRUE;
268        pixman_f_transform_multiply(f_transform, &rr_transform->f_transform,
269                                    f_transform);
270        pixman_f_transform_multiply(f_inverse, f_inverse,
271                                    &rr_transform->f_inverse);
272    }
273#endif
274    /*
275     * Compute the class of the resulting transform
276     */
277    if (!overflow && pixman_transform_is_identity(transform)) {
278        pixman_transform_init_translate(transform, F(x), F(y));
279
280        pixman_f_transform_init_translate(f_transform, x, y);
281        pixman_f_transform_init_translate(f_inverse, -x, -y);
282        return FALSE;
283    }
284    else {
285        pixman_f_transform_translate(f_transform, f_inverse, x, y);
286        if (!pixman_transform_translate(transform, &inverse, F(x), F(y)))
287            overflow = TRUE;
288        if (overflow) {
289            struct pixman_f_transform f_scaled;
290
291            f_scaled = *f_transform;
292            RRTransformRescale(&f_scaled, 16384.0);
293            pixman_transform_from_pixman_f_transform(transform, &f_scaled);
294        }
295        return TRUE;
296    }
297}
298