1 /*
2 * Copyright (C) 2007 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 #include <math.h>
18
19 #include <cutils/compiler.h>
20 #include <utils/String8.h>
21 #include <ui/Region.h>
22
23 #include "clz.h"
24 #include "Transform.h"
25
26 // ---------------------------------------------------------------------------
27
28 namespace android {
29
30 // ---------------------------------------------------------------------------
31
Transform()32 Transform::Transform() {
33 reset();
34 }
35
Transform(const Transform & other)36 Transform::Transform(const Transform& other)
37 : mMatrix(other.mMatrix), mType(other.mType) {
38 }
39
Transform(uint32_t orientation)40 Transform::Transform(uint32_t orientation) {
41 set(orientation, 0, 0);
42 }
43
~Transform()44 Transform::~Transform() {
45 }
46
47 static const float EPSILON = 0.0f;
48
isZero(float f)49 bool Transform::isZero(float f) {
50 return fabs(f) <= EPSILON;
51 }
52
absIsOne(float f)53 bool Transform::absIsOne(float f) {
54 return isZero(fabs(f) - 1.0f);
55 }
56
operator *(const Transform & rhs) const57 Transform Transform::operator * (const Transform& rhs) const
58 {
59 if (CC_LIKELY(mType == IDENTITY))
60 return rhs;
61
62 Transform r(*this);
63 if (rhs.mType == IDENTITY)
64 return r;
65
66 // TODO: we could use mType to optimize the matrix multiply
67 const mat33& A(mMatrix);
68 const mat33& B(rhs.mMatrix);
69 mat33& D(r.mMatrix);
70 for (int i=0 ; i<3 ; i++) {
71 const float v0 = A[0][i];
72 const float v1 = A[1][i];
73 const float v2 = A[2][i];
74 D[0][i] = v0*B[0][0] + v1*B[0][1] + v2*B[0][2];
75 D[1][i] = v0*B[1][0] + v1*B[1][1] + v2*B[1][2];
76 D[2][i] = v0*B[2][0] + v1*B[2][1] + v2*B[2][2];
77 }
78 r.mType |= rhs.mType;
79
80 // TODO: we could recompute this value from r and rhs
81 r.mType &= 0xFF;
82 r.mType |= UNKNOWN_TYPE;
83 return r;
84 }
85
operator [](size_t i) const86 const vec3& Transform::operator [] (size_t i) const {
87 return mMatrix[i];
88 }
89
transformed() const90 bool Transform::transformed() const {
91 return type() > TRANSLATE;
92 }
93
tx() const94 float Transform::tx() const {
95 return mMatrix[2][0];
96 }
97
ty() const98 float Transform::ty() const {
99 return mMatrix[2][1];
100 }
101
reset()102 void Transform::reset() {
103 mType = IDENTITY;
104 for(int i=0 ; i<3 ; i++) {
105 vec3& v(mMatrix[i]);
106 for (int j=0 ; j<3 ; j++)
107 v[j] = ((i==j) ? 1.0f : 0.0f);
108 }
109 }
110
set(float tx,float ty)111 void Transform::set(float tx, float ty)
112 {
113 mMatrix[2][0] = tx;
114 mMatrix[2][1] = ty;
115 mMatrix[2][2] = 1.0f;
116
117 if (isZero(tx) && isZero(ty)) {
118 mType &= ~TRANSLATE;
119 } else {
120 mType |= TRANSLATE;
121 }
122 }
123
set(float a,float b,float c,float d)124 void Transform::set(float a, float b, float c, float d)
125 {
126 mat33& M(mMatrix);
127 M[0][0] = a; M[1][0] = b;
128 M[0][1] = c; M[1][1] = d;
129 M[0][2] = 0; M[1][2] = 0;
130 mType = UNKNOWN_TYPE;
131 }
132
set(uint32_t flags,float w,float h)133 status_t Transform::set(uint32_t flags, float w, float h)
134 {
135 if (flags & ROT_INVALID) {
136 // that's not allowed!
137 reset();
138 return BAD_VALUE;
139 }
140
141 Transform H, V, R;
142 if (flags & ROT_90) {
143 // w & h are inverted when rotating by 90 degrees
144 swap(w, h);
145 }
146
147 if (flags & FLIP_H) {
148 H.mType = (FLIP_H << 8) | SCALE;
149 H.mType |= isZero(w) ? IDENTITY : TRANSLATE;
150 mat33& M(H.mMatrix);
151 M[0][0] = -1;
152 M[2][0] = w;
153 }
154
155 if (flags & FLIP_V) {
156 V.mType = (FLIP_V << 8) | SCALE;
157 V.mType |= isZero(h) ? IDENTITY : TRANSLATE;
158 mat33& M(V.mMatrix);
159 M[1][1] = -1;
160 M[2][1] = h;
161 }
162
163 if (flags & ROT_90) {
164 const float original_w = h;
165 R.mType = (ROT_90 << 8) | ROTATE;
166 R.mType |= isZero(original_w) ? IDENTITY : TRANSLATE;
167 mat33& M(R.mMatrix);
168 M[0][0] = 0; M[1][0] =-1; M[2][0] = original_w;
169 M[0][1] = 1; M[1][1] = 0;
170 }
171
172 *this = (R*(H*V));
173 return NO_ERROR;
174 }
175
transform(const vec2 & v) const176 vec2 Transform::transform(const vec2& v) const {
177 vec2 r;
178 const mat33& M(mMatrix);
179 r[0] = M[0][0]*v[0] + M[1][0]*v[1] + M[2][0];
180 r[1] = M[0][1]*v[0] + M[1][1]*v[1] + M[2][1];
181 return r;
182 }
183
transform(const vec3 & v) const184 vec3 Transform::transform(const vec3& v) const {
185 vec3 r;
186 const mat33& M(mMatrix);
187 r[0] = M[0][0]*v[0] + M[1][0]*v[1] + M[2][0]*v[2];
188 r[1] = M[0][1]*v[0] + M[1][1]*v[1] + M[2][1]*v[2];
189 r[2] = M[0][2]*v[0] + M[1][2]*v[1] + M[2][2]*v[2];
190 return r;
191 }
192
transform(int x,int y) const193 vec2 Transform::transform(int x, int y) const
194 {
195 return transform(vec2(x,y));
196 }
197
makeBounds(int w,int h) const198 Rect Transform::makeBounds(int w, int h) const
199 {
200 return transform( Rect(w, h) );
201 }
202
transform(const Rect & bounds) const203 Rect Transform::transform(const Rect& bounds) const
204 {
205 Rect r;
206 vec2 lt( bounds.left, bounds.top );
207 vec2 rt( bounds.right, bounds.top );
208 vec2 lb( bounds.left, bounds.bottom );
209 vec2 rb( bounds.right, bounds.bottom );
210
211 lt = transform(lt);
212 rt = transform(rt);
213 lb = transform(lb);
214 rb = transform(rb);
215
216 r.left = floorf(min(lt[0], rt[0], lb[0], rb[0]) + 0.5f);
217 r.top = floorf(min(lt[1], rt[1], lb[1], rb[1]) + 0.5f);
218 r.right = floorf(max(lt[0], rt[0], lb[0], rb[0]) + 0.5f);
219 r.bottom = floorf(max(lt[1], rt[1], lb[1], rb[1]) + 0.5f);
220
221 return r;
222 }
223
transform(const Region & reg) const224 Region Transform::transform(const Region& reg) const
225 {
226 Region out;
227 if (CC_UNLIKELY(transformed())) {
228 if (CC_LIKELY(preserveRects())) {
229 Region::const_iterator it = reg.begin();
230 Region::const_iterator const end = reg.end();
231 while (it != end) {
232 out.orSelf(transform(*it++));
233 }
234 } else {
235 out.set(transform(reg.bounds()));
236 }
237 } else {
238 int xpos = floorf(tx() + 0.5f);
239 int ypos = floorf(ty() + 0.5f);
240 out = reg.translate(xpos, ypos);
241 }
242 return out;
243 }
244
type() const245 uint32_t Transform::type() const
246 {
247 if (mType & UNKNOWN_TYPE) {
248 // recompute what this transform is
249
250 const mat33& M(mMatrix);
251 const float a = M[0][0];
252 const float b = M[1][0];
253 const float c = M[0][1];
254 const float d = M[1][1];
255 const float x = M[2][0];
256 const float y = M[2][1];
257
258 bool scale = false;
259 uint32_t flags = ROT_0;
260 if (isZero(b) && isZero(c)) {
261 if (a<0) flags |= FLIP_H;
262 if (d<0) flags |= FLIP_V;
263 if (!absIsOne(a) || !absIsOne(d)) {
264 scale = true;
265 }
266 } else if (isZero(a) && isZero(d)) {
267 flags |= ROT_90;
268 if (b>0) flags |= FLIP_V;
269 if (c<0) flags |= FLIP_H;
270 if (!absIsOne(b) || !absIsOne(c)) {
271 scale = true;
272 }
273 } else {
274 // there is a skew component and/or a non 90 degrees rotation
275 flags = ROT_INVALID;
276 }
277
278 mType = flags << 8;
279 if (flags & ROT_INVALID) {
280 mType |= UNKNOWN;
281 } else {
282 if ((flags & ROT_90) || ((flags & ROT_180) == ROT_180))
283 mType |= ROTATE;
284 if (flags & FLIP_H)
285 mType ^= SCALE;
286 if (flags & FLIP_V)
287 mType ^= SCALE;
288 if (scale)
289 mType |= SCALE;
290 }
291
292 if (!isZero(x) || !isZero(y))
293 mType |= TRANSLATE;
294 }
295 return mType;
296 }
297
inverse() const298 Transform Transform::inverse() const {
299 // our 3x3 matrix is always of the form of a 2x2 transformation
300 // followed by a translation: T*M, therefore:
301 // (T*M)^-1 = M^-1 * T^-1
302 Transform result;
303 if (mType <= TRANSLATE) {
304 // 1 0 0
305 // 0 1 0
306 // x y 1
307 result = *this;
308 result.mMatrix[2][0] = -result.mMatrix[2][0];
309 result.mMatrix[2][1] = -result.mMatrix[2][1];
310 } else {
311 // a c 0
312 // b d 0
313 // x y 1
314 const mat33& M(mMatrix);
315 const float a = M[0][0];
316 const float b = M[1][0];
317 const float c = M[0][1];
318 const float d = M[1][1];
319 const float x = M[2][0];
320 const float y = M[2][1];
321
322 const float idet = 1.0 / (a*d - b*c);
323 result.mMatrix[0][0] = d*idet;
324 result.mMatrix[0][1] = -c*idet;
325 result.mMatrix[1][0] = -b*idet;
326 result.mMatrix[1][1] = a*idet;
327 result.mType = mType;
328
329 vec2 T(-x, -y);
330 T = result.transform(T);
331 result.mMatrix[2][0] = T[0];
332 result.mMatrix[2][1] = T[1];
333 }
334 return result;
335 }
336
getType() const337 uint32_t Transform::getType() const {
338 return type() & 0xFF;
339 }
340
getOrientation() const341 uint32_t Transform::getOrientation() const
342 {
343 return (type() >> 8) & 0xFF;
344 }
345
preserveRects() const346 bool Transform::preserveRects() const
347 {
348 return (getOrientation() & ROT_INVALID) ? false : true;
349 }
350
dump(const char * name) const351 void Transform::dump(const char* name) const
352 {
353 type(); // updates the type
354
355 String8 flags, type;
356 const mat33& m(mMatrix);
357 uint32_t orient = mType >> 8;
358
359 if (orient&ROT_INVALID) {
360 flags.append("ROT_INVALID ");
361 } else {
362 if (orient&ROT_90) {
363 flags.append("ROT_90 ");
364 } else {
365 flags.append("ROT_0 ");
366 }
367 if (orient&FLIP_V)
368 flags.append("FLIP_V ");
369 if (orient&FLIP_H)
370 flags.append("FLIP_H ");
371 }
372
373 if (!(mType&(SCALE|ROTATE|TRANSLATE)))
374 type.append("IDENTITY ");
375 if (mType&SCALE)
376 type.append("SCALE ");
377 if (mType&ROTATE)
378 type.append("ROTATE ");
379 if (mType&TRANSLATE)
380 type.append("TRANSLATE ");
381
382 ALOGD("%s 0x%08x (%s, %s)", name, mType, flags.string(), type.string());
383 ALOGD("%.4f %.4f %.4f", m[0][0], m[1][0], m[2][0]);
384 ALOGD("%.4f %.4f %.4f", m[0][1], m[1][1], m[2][1]);
385 ALOGD("%.4f %.4f %.4f", m[0][2], m[1][2], m[2][2]);
386 }
387
388 // ---------------------------------------------------------------------------
389
390 }; // namespace android
391