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
tx() const90 float Transform::tx() const {
91 return mMatrix[2][0];
92 }
93
ty() const94 float Transform::ty() const {
95 return mMatrix[2][1];
96 }
97
reset()98 void Transform::reset() {
99 mType = IDENTITY;
100 for(int i=0 ; i<3 ; i++) {
101 vec3& v(mMatrix[i]);
102 for (int j=0 ; j<3 ; j++)
103 v[j] = ((i==j) ? 1.0f : 0.0f);
104 }
105 }
106
set(float tx,float ty)107 void Transform::set(float tx, float ty)
108 {
109 mMatrix[2][0] = tx;
110 mMatrix[2][1] = ty;
111 mMatrix[2][2] = 1.0f;
112
113 if (isZero(tx) && isZero(ty)) {
114 mType &= ~TRANSLATE;
115 } else {
116 mType |= TRANSLATE;
117 }
118 }
119
set(float a,float b,float c,float d)120 void Transform::set(float a, float b, float c, float d)
121 {
122 mat33& M(mMatrix);
123 M[0][0] = a; M[1][0] = b;
124 M[0][1] = c; M[1][1] = d;
125 M[0][2] = 0; M[1][2] = 0;
126 mType = UNKNOWN_TYPE;
127 }
128
set(uint32_t flags,float w,float h)129 status_t Transform::set(uint32_t flags, float w, float h)
130 {
131 if (flags & ROT_INVALID) {
132 // that's not allowed!
133 reset();
134 return BAD_VALUE;
135 }
136
137 Transform H, V, R;
138 if (flags & ROT_90) {
139 // w & h are inverted when rotating by 90 degrees
140 swap(w, h);
141 }
142
143 if (flags & FLIP_H) {
144 H.mType = (FLIP_H << 8) | SCALE;
145 H.mType |= isZero(w) ? IDENTITY : TRANSLATE;
146 mat33& M(H.mMatrix);
147 M[0][0] = -1;
148 M[2][0] = w;
149 }
150
151 if (flags & FLIP_V) {
152 V.mType = (FLIP_V << 8) | SCALE;
153 V.mType |= isZero(h) ? IDENTITY : TRANSLATE;
154 mat33& M(V.mMatrix);
155 M[1][1] = -1;
156 M[2][1] = h;
157 }
158
159 if (flags & ROT_90) {
160 const float original_w = h;
161 R.mType = (ROT_90 << 8) | ROTATE;
162 R.mType |= isZero(original_w) ? IDENTITY : TRANSLATE;
163 mat33& M(R.mMatrix);
164 M[0][0] = 0; M[1][0] =-1; M[2][0] = original_w;
165 M[0][1] = 1; M[1][1] = 0;
166 }
167
168 *this = (R*(H*V));
169 return NO_ERROR;
170 }
171
transform(const vec2 & v) const172 vec2 Transform::transform(const vec2& v) const {
173 vec2 r;
174 const mat33& M(mMatrix);
175 r[0] = M[0][0]*v[0] + M[1][0]*v[1] + M[2][0];
176 r[1] = M[0][1]*v[0] + M[1][1]*v[1] + M[2][1];
177 return r;
178 }
179
transform(const vec3 & v) const180 vec3 Transform::transform(const vec3& v) const {
181 vec3 r;
182 const mat33& M(mMatrix);
183 r[0] = M[0][0]*v[0] + M[1][0]*v[1] + M[2][0]*v[2];
184 r[1] = M[0][1]*v[0] + M[1][1]*v[1] + M[2][1]*v[2];
185 r[2] = M[0][2]*v[0] + M[1][2]*v[1] + M[2][2]*v[2];
186 return r;
187 }
188
transform(int x,int y) const189 vec2 Transform::transform(int x, int y) const
190 {
191 return transform(vec2(x,y));
192 }
193
makeBounds(int w,int h) const194 Rect Transform::makeBounds(int w, int h) const
195 {
196 return transform( Rect(w, h) );
197 }
198
transform(const Rect & bounds) const199 Rect Transform::transform(const Rect& bounds) const
200 {
201 Rect r;
202 vec2 lt( bounds.left, bounds.top );
203 vec2 rt( bounds.right, bounds.top );
204 vec2 lb( bounds.left, bounds.bottom );
205 vec2 rb( bounds.right, bounds.bottom );
206
207 lt = transform(lt);
208 rt = transform(rt);
209 lb = transform(lb);
210 rb = transform(rb);
211
212 r.left = floorf(min(lt[0], rt[0], lb[0], rb[0]) + 0.5f);
213 r.top = floorf(min(lt[1], rt[1], lb[1], rb[1]) + 0.5f);
214 r.right = floorf(max(lt[0], rt[0], lb[0], rb[0]) + 0.5f);
215 r.bottom = floorf(max(lt[1], rt[1], lb[1], rb[1]) + 0.5f);
216
217 return r;
218 }
219
transform(const Region & reg) const220 Region Transform::transform(const Region& reg) const
221 {
222 Region out;
223 if (CC_UNLIKELY(type() > TRANSLATE)) {
224 if (CC_LIKELY(preserveRects())) {
225 Region::const_iterator it = reg.begin();
226 Region::const_iterator const end = reg.end();
227 while (it != end) {
228 out.orSelf(transform(*it++));
229 }
230 } else {
231 out.set(transform(reg.bounds()));
232 }
233 } else {
234 int xpos = floorf(tx() + 0.5f);
235 int ypos = floorf(ty() + 0.5f);
236 out = reg.translate(xpos, ypos);
237 }
238 return out;
239 }
240
type() const241 uint32_t Transform::type() const
242 {
243 if (mType & UNKNOWN_TYPE) {
244 // recompute what this transform is
245
246 const mat33& M(mMatrix);
247 const float a = M[0][0];
248 const float b = M[1][0];
249 const float c = M[0][1];
250 const float d = M[1][1];
251 const float x = M[2][0];
252 const float y = M[2][1];
253
254 bool scale = false;
255 uint32_t flags = ROT_0;
256 if (isZero(b) && isZero(c)) {
257 if (a<0) flags |= FLIP_H;
258 if (d<0) flags |= FLIP_V;
259 if (!absIsOne(a) || !absIsOne(d)) {
260 scale = true;
261 }
262 } else if (isZero(a) && isZero(d)) {
263 flags |= ROT_90;
264 if (b>0) flags |= FLIP_V;
265 if (c<0) flags |= FLIP_H;
266 if (!absIsOne(b) || !absIsOne(c)) {
267 scale = true;
268 }
269 } else {
270 // there is a skew component and/or a non 90 degrees rotation
271 flags = ROT_INVALID;
272 }
273
274 mType = flags << 8;
275 if (flags & ROT_INVALID) {
276 mType |= UNKNOWN;
277 } else {
278 if ((flags & ROT_90) || ((flags & ROT_180) == ROT_180))
279 mType |= ROTATE;
280 if (flags & FLIP_H)
281 mType ^= SCALE;
282 if (flags & FLIP_V)
283 mType ^= SCALE;
284 if (scale)
285 mType |= SCALE;
286 }
287
288 if (!isZero(x) || !isZero(y))
289 mType |= TRANSLATE;
290 }
291 return mType;
292 }
293
inverse() const294 Transform Transform::inverse() const {
295 // our 3x3 matrix is always of the form of a 2x2 transformation
296 // followed by a translation: T*M, therefore:
297 // (T*M)^-1 = M^-1 * T^-1
298 Transform result;
299 if (mType <= TRANSLATE) {
300 // 1 0 0
301 // 0 1 0
302 // x y 1
303 result = *this;
304 result.mMatrix[2][0] = -result.mMatrix[2][0];
305 result.mMatrix[2][1] = -result.mMatrix[2][1];
306 } else {
307 // a c 0
308 // b d 0
309 // x y 1
310 const mat33& M(mMatrix);
311 const float a = M[0][0];
312 const float b = M[1][0];
313 const float c = M[0][1];
314 const float d = M[1][1];
315 const float x = M[2][0];
316 const float y = M[2][1];
317
318 const float idet = 1.0 / (a*d - b*c);
319 result.mMatrix[0][0] = d*idet;
320 result.mMatrix[0][1] = -c*idet;
321 result.mMatrix[1][0] = -b*idet;
322 result.mMatrix[1][1] = a*idet;
323 result.mType = mType;
324
325 vec2 T(-x, -y);
326 T = result.transform(T);
327 result.mMatrix[2][0] = T[0];
328 result.mMatrix[2][1] = T[1];
329 }
330 return result;
331 }
332
getType() const333 uint32_t Transform::getType() const {
334 return type() & 0xFF;
335 }
336
getOrientation() const337 uint32_t Transform::getOrientation() const
338 {
339 return (type() >> 8) & 0xFF;
340 }
341
preserveRects() const342 bool Transform::preserveRects() const
343 {
344 return (getOrientation() & ROT_INVALID) ? false : true;
345 }
346
dump(const char * name) const347 void Transform::dump(const char* name) const
348 {
349 type(); // updates the type
350
351 String8 flags, type;
352 const mat33& m(mMatrix);
353 uint32_t orient = mType >> 8;
354
355 if (orient&ROT_INVALID) {
356 flags.append("ROT_INVALID ");
357 } else {
358 if (orient&ROT_90) {
359 flags.append("ROT_90 ");
360 } else {
361 flags.append("ROT_0 ");
362 }
363 if (orient&FLIP_V)
364 flags.append("FLIP_V ");
365 if (orient&FLIP_H)
366 flags.append("FLIP_H ");
367 }
368
369 if (!(mType&(SCALE|ROTATE|TRANSLATE)))
370 type.append("IDENTITY ");
371 if (mType&SCALE)
372 type.append("SCALE ");
373 if (mType&ROTATE)
374 type.append("ROTATE ");
375 if (mType&TRANSLATE)
376 type.append("TRANSLATE ");
377
378 ALOGD("%s 0x%08x (%s, %s)", name, mType, flags.string(), type.string());
379 ALOGD("%.4f %.4f %.4f", m[0][0], m[1][0], m[2][0]);
380 ALOGD("%.4f %.4f %.4f", m[0][1], m[1][1], m[2][1]);
381 ALOGD("%.4f %.4f %.4f", m[0][2], m[1][2], m[2][2]);
382 }
383
384 // ---------------------------------------------------------------------------
385
386 }; // namespace android
387