1 /*
2  * Copyright 1998-1999 Precision Insight, Inc., Cedar Park, Texas.  All Rights Reserved.
3  * Copyright (c) 2005 Jesse Barnes <jbarnes@virtuousgeek.org>
4  * Copyright © 2010 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  * Authors:
26  *    Jesse Barns <jbarnes@virtuousgeek.org>
27  *    Chris Wilson <chris@chris-wilson.co.uk>
28  */
29 
30 #ifdef HAVE_CONFIG_H
31 #include "config.h"
32 #endif
33 
34 #include "sna.h"
35 
36 /**
37  * Returns whether the provided transform is affine.
38  *
39  * transform may be null.
40  */
sna_transform_is_affine(const PictTransform * t)41 bool sna_transform_is_affine(const PictTransform *t)
42 {
43 	if (t == NULL)
44 		return true;
45 
46 	return t->matrix[2][0] == 0 && t->matrix[2][1] == 0;
47 }
48 
49 bool
sna_transform_is_translation(const PictTransform * t,pixman_fixed_t * tx,pixman_fixed_t * ty)50 sna_transform_is_translation(const PictTransform *t,
51 			     pixman_fixed_t *tx,
52 			     pixman_fixed_t *ty)
53 {
54 	if (t == NULL) {
55 		*tx = *ty = 0;
56 		return true;
57 	}
58 
59 	if (t->matrix[0][0] != IntToxFixed(1) ||
60 	    t->matrix[0][1] != 0 ||
61 	    t->matrix[1][0] != 0 ||
62 	    t->matrix[1][1] != IntToxFixed(1) ||
63 	    t->matrix[2][0] != 0 ||
64 	    t->matrix[2][1] != 0 ||
65 	    t->matrix[2][2] != IntToxFixed(1))
66 		return false;
67 
68 	*tx = t->matrix[0][2];
69 	*ty = t->matrix[1][2];
70 	return true;
71 }
72 
73 bool
sna_transform_is_integer_translation(const PictTransform * t,int16_t * tx,int16_t * ty)74 sna_transform_is_integer_translation(const PictTransform *t, int16_t *tx, int16_t *ty)
75 {
76 	if (t == NULL) {
77 		*tx = *ty = 0;
78 		return true;
79 	}
80 
81 	if (t->matrix[0][0] != IntToxFixed(1) ||
82 	    t->matrix[0][1] != 0 ||
83 	    t->matrix[1][0] != 0 ||
84 	    t->matrix[1][1] != IntToxFixed(1) ||
85 	    t->matrix[2][0] != 0 ||
86 	    t->matrix[2][1] != 0 ||
87 	    t->matrix[2][2] != IntToxFixed(1))
88 		return false;
89 
90 	if (pixman_fixed_fraction(t->matrix[0][2]) ||
91 	    pixman_fixed_fraction(t->matrix[1][2]))
92 		return false;
93 
94 	*tx = pixman_fixed_to_int(t->matrix[0][2]);
95 	*ty = pixman_fixed_to_int(t->matrix[1][2]);
96 	return true;
97 }
98 
99 bool
sna_transform_is_imprecise_integer_translation(const PictTransform * t,int filter,bool precise,int16_t * tx,int16_t * ty)100 sna_transform_is_imprecise_integer_translation(const PictTransform *t,
101 					       int filter, bool precise,
102 					       int16_t *tx, int16_t *ty)
103 {
104 	if (t == NULL) {
105 		DBG(("%s: no transform\n", __FUNCTION__));
106 		*tx = *ty = 0;
107 		return true;
108 	}
109 
110 	DBG(("%s: FilterNearest?=%d, precise?=%d, transform=[%f %f %f, %f %f %f, %f %f %f]\n",
111 	     __FUNCTION__, filter==PictFilterNearest, precise,
112 	     t->matrix[0][0]/65536., t->matrix[0][1]/65536., t->matrix[0][2]/65536.,
113 	     t->matrix[1][0]/65536., t->matrix[1][1]/65536., t->matrix[1][2]/65536.,
114 	     t->matrix[2][0]/65536., t->matrix[2][1]/65536., t->matrix[2][2]/65536.));
115 
116 	if (t->matrix[0][0] != IntToxFixed(1) ||
117 	    t->matrix[0][1] != 0 ||
118 	    t->matrix[1][0] != 0 ||
119 	    t->matrix[1][1] != IntToxFixed(1) ||
120 	    t->matrix[2][0] != 0 ||
121 	    t->matrix[2][1] != 0 ||
122 	    t->matrix[2][2] != IntToxFixed(1)) {
123 		DBG(("%s: not unity scaling\n", __FUNCTION__));
124 		return false;
125 	}
126 
127 	if (filter != PictFilterNearest) {
128 		if (precise) {
129 			if (pixman_fixed_fraction(t->matrix[0][2]) ||
130 			    pixman_fixed_fraction(t->matrix[1][2])) {
131 				DBG(("%s: precise, fractional translation\n", __FUNCTION__));
132 				return false;
133 			}
134 		} else {
135 			int f;
136 
137 			f = pixman_fixed_fraction(t->matrix[0][2]);
138 			if (f > IntToxFixed(1)/4 && f < IntToxFixed(3)/4) {
139 				DBG(("%s: imprecise, fractional translation X: %x\n", __FUNCTION__, f));
140 				return false;
141 			}
142 
143 			f = pixman_fixed_fraction(t->matrix[1][2]);
144 			if (f > IntToxFixed(1)/4 && f < IntToxFixed(3)/4) {
145 				DBG(("%s: imprecise, fractional translation Y: %x\n", __FUNCTION__, f));
146 				return false;
147 			}
148 		}
149 	}
150 
151 	*tx = pixman_fixed_to_int(t->matrix[0][2] + IntToxFixed(1)/2);
152 	*ty = pixman_fixed_to_int(t->matrix[1][2] + IntToxFixed(1)/2);
153 	return true;
154 }
155 
156 /**
157  * Returns the floating-point coordinates transformed by the given transform.
158  */
159 void
sna_get_transformed_coordinates(int x,int y,const PictTransform * transform,float * x_out,float * y_out)160 sna_get_transformed_coordinates(int x, int y,
161 			       	const PictTransform *transform,
162 				float *x_out, float *y_out)
163 {
164 	if (transform == NULL) {
165 		*x_out = x;
166 		*y_out = y;
167 	} else
168 		_sna_get_transformed_coordinates(x, y, transform, x_out, y_out);
169 }
170 
171 /**
172  * Returns the un-normalized floating-point coordinates transformed by the given transform.
173  */
174 void
sna_get_transformed_coordinates_3d(int x,int y,const PictTransform * transform,float * x_out,float * y_out,float * w_out)175 sna_get_transformed_coordinates_3d(int x, int y,
176 				   const PictTransform *transform,
177 				   float *x_out, float *y_out, float *w_out)
178 {
179 	if (transform == NULL) {
180 		*x_out = x;
181 		*y_out = y;
182 		*w_out = 1;
183 	} else {
184 		int64_t result[3];
185 
186 		if (_sna_transform_point(transform, x, y, result)) {
187 			*x_out = result[0] / 65536.;
188 			*y_out = result[1] / 65536.;
189 			*w_out = result[2] / 65536.;
190 		} else {
191 			*x_out = *y_out = 0;
192 			*w_out = 1.;
193 		}
194 	}
195 }
196