PathCache.cpp revision 0a8c51b1d0d66d6060afcec1eab33091d49332ae 
1/*
2 * Copyright (C) 2013 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#define LOG_TAG "OpenGLRenderer"
18#define ATRACE_TAG ATRACE_TAG_VIEW
19
20#include <SkBitmap.h>
21#include <SkCanvas.h>
22#include <SkPaint.h>
23#include <SkPath.h>
24#include <SkRect.h>
25
26#include <utils/JenkinsHash.h>
27#include <utils/Trace.h>
28
29#include "Caches.h"
30#include "PathCache.h"
31
32#include "thread/Signal.h"
33#include "thread/Task.h"
34#include "thread/TaskProcessor.h"
35
36namespace android {
37namespace uirenderer {
38
39///////////////////////////////////////////////////////////////////////////////
40// Cache entries
41///////////////////////////////////////////////////////////////////////////////
42
43PathDescription::PathDescription():
44        type(kShapeNone),
45        join(SkPaint::kDefault_Join),
46        cap(SkPaint::kDefault_Cap),
47        style(SkPaint::kFill_Style),
48        miter(4.0f),
49        strokeWidth(1.0f),
50        pathEffect(NULL) {
51    memset(&shape, 0, sizeof(Shape));
52}
53
54PathDescription::PathDescription(ShapeType type, SkPaint* paint):
55        type(type),
56        join(paint->getStrokeJoin()),
57        cap(paint->getStrokeCap()),
58        style(paint->getStyle()),
59        miter(paint->getStrokeMiter()),
60        strokeWidth(paint->getStrokeWidth()),
61        pathEffect(paint->getPathEffect()) {
62    memset(&shape, 0, sizeof(Shape));
63}
64
65hash_t PathDescription::hash() const {
66    uint32_t hash = JenkinsHashMix(0, type);
67    hash = JenkinsHashMix(hash, join);
68    hash = JenkinsHashMix(hash, cap);
69    hash = JenkinsHashMix(hash, style);
70    hash = JenkinsHashMix(hash, android::hash_type(miter));
71    hash = JenkinsHashMix(hash, android::hash_type(strokeWidth));
72    hash = JenkinsHashMix(hash, android::hash_type(pathEffect));
73    hash = JenkinsHashMixBytes(hash, (uint8_t*) &shape, sizeof(Shape));
74    return JenkinsHashWhiten(hash);
75}
76
77int PathDescription::compare(const PathDescription& rhs) const {
78    return memcmp(this, &rhs, sizeof(PathDescription));
79}
80
81///////////////////////////////////////////////////////////////////////////////
82// Utilities
83///////////////////////////////////////////////////////////////////////////////
84
85bool PathCache::canDrawAsConvexPath(SkPath* path, SkPaint* paint) {
86    // NOTE: This should only be used after PathTessellator handles joins properly
87    return paint->getPathEffect() == NULL && path->getConvexity() == SkPath::kConvex_Convexity;
88}
89
90void PathCache::computePathBounds(const SkPath* path, const SkPaint* paint,
91        float& left, float& top, float& offset, uint32_t& width, uint32_t& height) {
92    const SkRect& bounds = path->getBounds();
93    PathCache::computeBounds(bounds, paint, left, top, offset, width, height);
94}
95
96void PathCache::computeBounds(const SkRect& bounds, const SkPaint* paint,
97        float& left, float& top, float& offset, uint32_t& width, uint32_t& height) {
98    const float pathWidth = fmax(bounds.width(), 1.0f);
99    const float pathHeight = fmax(bounds.height(), 1.0f);
100
101    left = bounds.fLeft;
102    top = bounds.fTop;
103
104    offset = (int) floorf(fmax(paint->getStrokeWidth(), 1.0f) * 1.5f + 0.5f);
105
106    width = uint32_t(pathWidth + offset * 2.0 + 0.5);
107    height = uint32_t(pathHeight + offset * 2.0 + 0.5);
108}
109
110static void initBitmap(SkBitmap& bitmap, uint32_t width, uint32_t height) {
111    bitmap.setConfig(SkBitmap::kA8_Config, width, height);
112    bitmap.allocPixels();
113    bitmap.eraseColor(0);
114}
115
116static void initPaint(SkPaint& paint) {
117    // Make sure the paint is opaque, color, alpha, filter, etc.
118    // will be applied later when compositing the alpha8 texture
119    paint.setColor(0xff000000);
120    paint.setAlpha(255);
121    paint.setColorFilter(NULL);
122    paint.setMaskFilter(NULL);
123    paint.setShader(NULL);
124    SkXfermode* mode = SkXfermode::Create(SkXfermode::kSrc_Mode);
125    SkSafeUnref(paint.setXfermode(mode));
126}
127
128static void drawPath(const SkPath *path, const SkPaint* paint, SkBitmap& bitmap,
129        float left, float top, float offset, uint32_t width, uint32_t height) {
130    initBitmap(bitmap, width, height);
131
132    SkPaint pathPaint(*paint);
133    initPaint(pathPaint);
134
135    SkCanvas canvas(bitmap);
136    canvas.translate(-left + offset, -top + offset);
137    canvas.drawPath(*path, pathPaint);
138}
139
140static PathTexture* createTexture(float left, float top, float offset,
141        uint32_t width, uint32_t height, uint32_t id) {
142    PathTexture* texture = new PathTexture(Caches::getInstance());
143    texture->left = left;
144    texture->top = top;
145    texture->offset = offset;
146    texture->width = width;
147    texture->height = height;
148    texture->generation = id;
149    return texture;
150}
151
152///////////////////////////////////////////////////////////////////////////////
153// Cache constructor/destructor
154///////////////////////////////////////////////////////////////////////////////
155
156PathCache::PathCache():
157        mCache(LruCache<PathDescription, PathTexture*>::kUnlimitedCapacity),
158        mSize(0), mMaxSize(MB(DEFAULT_PATH_CACHE_SIZE)) {
159    char property[PROPERTY_VALUE_MAX];
160    if (property_get(PROPERTY_PATH_CACHE_SIZE, property, NULL) > 0) {
161        INIT_LOGD("  Setting %s cache size to %sMB", name, property);
162        setMaxSize(MB(atof(property)));
163    } else {
164        INIT_LOGD("  Using default %s cache size of %.2fMB", name, DEFAULT_PATH_CACHE_SIZE);
165    }
166    init();
167}
168
169PathCache::~PathCache() {
170    mCache.clear();
171}
172
173void PathCache::init() {
174    mCache.setOnEntryRemovedListener(this);
175
176    GLint maxTextureSize;
177    glGetIntegerv(GL_MAX_TEXTURE_SIZE, &maxTextureSize);
178    mMaxTextureSize = maxTextureSize;
179
180    mDebugEnabled = readDebugLevel() & kDebugCaches;
181}
182
183///////////////////////////////////////////////////////////////////////////////
184// Size management
185///////////////////////////////////////////////////////////////////////////////
186
187uint32_t PathCache::getSize() {
188    return mSize;
189}
190
191uint32_t PathCache::getMaxSize() {
192    return mMaxSize;
193}
194
195void PathCache::setMaxSize(uint32_t maxSize) {
196    mMaxSize = maxSize;
197    while (mSize > mMaxSize) {
198        mCache.removeOldest();
199    }
200}
201
202///////////////////////////////////////////////////////////////////////////////
203// Callbacks
204///////////////////////////////////////////////////////////////////////////////
205
206void PathCache::operator()(PathDescription& entry, PathTexture*& texture) {
207    removeTexture(texture);
208}
209
210///////////////////////////////////////////////////////////////////////////////
211// Caching
212///////////////////////////////////////////////////////////////////////////////
213
214void PathCache::removeTexture(PathTexture* texture) {
215    if (texture) {
216        const uint32_t size = texture->width * texture->height;
217        mSize -= size;
218
219        PATH_LOGD("PathCache::delete name, size, mSize = %d, %d, %d",
220                texture->id, size, mSize);
221        if (mDebugEnabled) {
222            ALOGD("Shape deleted, size = %d", size);
223        }
224
225        if (texture->id) {
226            Caches::getInstance().deleteTexture(texture->id);
227        }
228        delete texture;
229    }
230}
231
232void PathCache::purgeCache(uint32_t width, uint32_t height) {
233    const uint32_t size = width * height;
234    // Don't even try to cache a bitmap that's bigger than the cache
235    if (size < mMaxSize) {
236        while (mSize + size > mMaxSize) {
237            mCache.removeOldest();
238        }
239    }
240}
241
242void PathCache::trim() {
243    while (mSize > mMaxSize) {
244        mCache.removeOldest();
245    }
246}
247
248PathTexture* PathCache::addTexture(const PathDescription& entry, const SkPath *path,
249        const SkPaint* paint) {
250    ATRACE_CALL();
251
252    float left, top, offset;
253    uint32_t width, height;
254    computePathBounds(path, paint, left, top, offset, width, height);
255
256    if (!checkTextureSize(width, height)) return NULL;
257
258    purgeCache(width, height);
259
260    SkBitmap bitmap;
261    drawPath(path, paint, bitmap, left, top, offset, width, height);
262
263    PathTexture* texture = createTexture(left, top, offset, width, height,
264            path->getGenerationID());
265    generateTexture(entry, &bitmap, texture);
266
267    return texture;
268}
269
270void PathCache::generateTexture(const PathDescription& entry, SkBitmap* bitmap,
271        PathTexture* texture, bool addToCache) {
272    generateTexture(*bitmap, texture);
273
274    uint32_t size = texture->width * texture->height;
275    if (size < mMaxSize) {
276        mSize += size;
277        PATH_LOGD("PathCache::get/create: name, size, mSize = %d, %d, %d",
278                texture->id, size, mSize);
279        if (mDebugEnabled) {
280            ALOGD("Shape created, size = %d", size);
281        }
282        if (addToCache) {
283            mCache.put(entry, texture);
284        }
285    } else {
286        // It's okay to add a texture that's bigger than the cache since
287        // we'll trim the cache later when addToCache is set to false
288        if (!addToCache) {
289            mSize += size;
290        }
291        texture->cleanup = true;
292    }
293}
294
295void PathCache::clear() {
296    mCache.clear();
297}
298
299void PathCache::generateTexture(SkBitmap& bitmap, Texture* texture) {
300    SkAutoLockPixels alp(bitmap);
301    if (!bitmap.readyToDraw()) {
302        ALOGE("Cannot generate texture from bitmap");
303        return;
304    }
305
306    glGenTextures(1, &texture->id);
307
308    Caches::getInstance().bindTexture(texture->id);
309    // Textures are Alpha8
310    glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
311
312    texture->blend = true;
313    glTexImage2D(GL_TEXTURE_2D, 0, GL_ALPHA, texture->width, texture->height, 0,
314            GL_ALPHA, GL_UNSIGNED_BYTE, bitmap.getPixels());
315
316    texture->setFilter(GL_LINEAR);
317    texture->setWrap(GL_CLAMP_TO_EDGE);
318}
319
320///////////////////////////////////////////////////////////////////////////////
321// Path precaching
322///////////////////////////////////////////////////////////////////////////////
323
324PathCache::PathProcessor::PathProcessor(Caches& caches):
325        TaskProcessor<SkBitmap*>(&caches.tasks), mMaxTextureSize(caches.maxTextureSize) {
326}
327
328void PathCache::PathProcessor::onProcess(const sp<Task<SkBitmap*> >& task) {
329    sp<PathTask> t = static_cast<PathTask* >(task.get());
330    ATRACE_NAME("pathPrecache");
331
332    float left, top, offset;
333    uint32_t width, height;
334    PathCache::computePathBounds(t->path, t->paint, left, top, offset, width, height);
335
336    PathTexture* texture = t->texture;
337    texture->left = left;
338    texture->top = top;
339    texture->offset = offset;
340    texture->width = width;
341    texture->height = height;
342
343    if (width <= mMaxTextureSize && height <= mMaxTextureSize) {
344        SkBitmap* bitmap = new SkBitmap();
345        drawPath(t->path, t->paint, *bitmap, left, top, offset, width, height);
346        t->setResult(bitmap);
347    } else {
348        texture->width = 0;
349        texture->height = 0;
350        t->setResult(NULL);
351    }
352}
353
354///////////////////////////////////////////////////////////////////////////////
355// Paths
356///////////////////////////////////////////////////////////////////////////////
357
358void PathCache::remove(Vector<PathDescription>& pathsToRemove, const path_pair_t& pair) {
359    LruCache<PathDescription, PathTexture*>::Iterator i(mCache);
360
361    while (i.next()) {
362        const PathDescription& key = i.key();
363        if (key.type == kShapePath &&
364                (key.shape.path.mPath == pair.getFirst() ||
365                        key.shape.path.mPath == pair.getSecond())) {
366            pathsToRemove.push(key);
367        }
368    }
369}
370
371void PathCache::removeDeferred(SkPath* path) {
372    Mutex::Autolock l(mLock);
373    mGarbage.push(path_pair_t(path, const_cast<SkPath*>(path->getSourcePath())));
374}
375
376void PathCache::clearGarbage() {
377    Vector<PathDescription> pathsToRemove;
378
379    { // scope for the mutex
380        Mutex::Autolock l(mLock);
381        size_t count = mGarbage.size();
382        for (size_t i = 0; i < count; i++) {
383            remove(pathsToRemove, mGarbage.itemAt(i));
384        }
385        mGarbage.clear();
386    }
387
388    for (size_t i = 0; i < pathsToRemove.size(); i++) {
389        mCache.remove(pathsToRemove.itemAt(i));
390    }
391}
392
393/**
394 * To properly handle path mutations at draw time we always make a copy
395 * of paths objects when recording display lists. The source path points
396 * to the path we originally copied the path from. This ensures we use
397 * the original path as a cache key the first time a path is inserted
398 * in the cache. The source path is also used to reclaim garbage when a
399 * Dalvik Path object is collected.
400 */
401static SkPath* getSourcePath(SkPath* path) {
402    const SkPath* sourcePath = path->getSourcePath();
403    if (sourcePath && sourcePath->getGenerationID() == path->getGenerationID()) {
404        return const_cast<SkPath*>(sourcePath);
405    }
406    return path;
407}
408
409PathTexture* PathCache::get(SkPath* path, SkPaint* paint) {
410    path = getSourcePath(path);
411
412    PathDescription entry(kShapePath, paint);
413    entry.shape.path.mPath = path;
414
415    PathTexture* texture = mCache.get(entry);
416
417    if (!texture) {
418        texture = addTexture(entry, path, paint);
419    } else {
420        // A bitmap is attached to the texture, this means we need to
421        // upload it as a GL texture
422        const sp<Task<SkBitmap*> >& task = texture->task();
423        if (task != NULL) {
424            // But we must first wait for the worker thread to be done
425            // producing the bitmap, so let's wait
426            SkBitmap* bitmap = task->getResult();
427            if (bitmap) {
428                generateTexture(entry, bitmap, texture, false);
429                texture->clearTask();
430            } else {
431                ALOGW("Path too large to be rendered into a texture");
432                texture->clearTask();
433                texture = NULL;
434                mCache.remove(entry);
435            }
436        } else if (path->getGenerationID() != texture->generation) {
437            // The size of the path might have changed so we first
438            // remove the entry from the cache
439            mCache.remove(entry);
440            texture = addTexture(entry, path, paint);
441        }
442    }
443
444    return texture;
445}
446
447void PathCache::precache(SkPath* path, SkPaint* paint) {
448    if (!Caches::getInstance().tasks.canRunTasks()) {
449        return;
450    }
451
452    path = getSourcePath(path);
453
454    PathDescription entry(kShapePath, paint);
455    entry.shape.path.mPath = path;
456
457    PathTexture* texture = mCache.get(entry);
458
459    bool generate = false;
460    if (!texture) {
461        generate = true;
462    } else if (path->getGenerationID() != texture->generation) {
463        mCache.remove(entry);
464        generate = true;
465    }
466
467    if (generate) {
468        // It is important to specify the generation ID so we do not
469        // attempt to precache the same path several times
470        texture = createTexture(0.0f, 0.0f, 0.0f, 0, 0, path->getGenerationID());
471        sp<PathTask> task = new PathTask(path, paint, texture);
472        texture->setTask(task);
473
474        // During the precaching phase we insert path texture objects into
475        // the cache that do not point to any GL texture. They are instead
476        // treated as a task for the precaching worker thread. This is why
477        // we do not check the cache limit when inserting these objects.
478        // The conversion into GL texture will happen in get(), when a client
479        // asks for a path texture. This is also when the cache limit will
480        // be enforced.
481        mCache.put(entry, texture);
482
483        if (mProcessor == NULL) {
484            mProcessor = new PathProcessor(Caches::getInstance());
485        }
486        mProcessor->add(task);
487    }
488}
489
490///////////////////////////////////////////////////////////////////////////////
491// Rounded rects
492///////////////////////////////////////////////////////////////////////////////
493
494PathTexture* PathCache::getRoundRect(float width, float height,
495        float rx, float ry, SkPaint* paint) {
496    PathDescription entry(kShapeRoundRect, paint);
497    entry.shape.roundRect.mWidth = width;
498    entry.shape.roundRect.mHeight = height;
499    entry.shape.roundRect.mRx = rx;
500    entry.shape.roundRect.mRy = ry;
501
502    PathTexture* texture = get(entry);
503
504    if (!texture) {
505        SkPath path;
506        SkRect r;
507        r.set(0.0f, 0.0f, width, height);
508        path.addRoundRect(r, rx, ry, SkPath::kCW_Direction);
509
510        texture = addTexture(entry, &path, paint);
511    }
512
513    return texture;
514}
515
516///////////////////////////////////////////////////////////////////////////////
517// Circles
518///////////////////////////////////////////////////////////////////////////////
519
520PathTexture* PathCache::getCircle(float radius, SkPaint* paint) {
521    PathDescription entry(kShapeCircle, paint);
522    entry.shape.circle.mRadius = radius;
523
524    PathTexture* texture = get(entry);
525
526    if (!texture) {
527        SkPath path;
528        path.addCircle(radius, radius, radius, SkPath::kCW_Direction);
529
530        texture = addTexture(entry, &path, paint);
531    }
532
533    return texture;
534}
535
536///////////////////////////////////////////////////////////////////////////////
537// Ovals
538///////////////////////////////////////////////////////////////////////////////
539
540PathTexture* PathCache::getOval(float width, float height, SkPaint* paint) {
541    PathDescription entry(kShapeOval, paint);
542    entry.shape.oval.mWidth = width;
543    entry.shape.oval.mHeight = height;
544
545    PathTexture* texture = get(entry);
546
547    if (!texture) {
548        SkPath path;
549        SkRect r;
550        r.set(0.0f, 0.0f, width, height);
551        path.addOval(r, SkPath::kCW_Direction);
552
553        texture = addTexture(entry, &path, paint);
554    }
555
556    return texture;
557}
558
559///////////////////////////////////////////////////////////////////////////////
560// Rects
561///////////////////////////////////////////////////////////////////////////////
562
563PathTexture* PathCache::getRect(float width, float height, SkPaint* paint) {
564    PathDescription entry(kShapeRect, paint);
565    entry.shape.rect.mWidth = width;
566    entry.shape.rect.mHeight = height;
567
568    PathTexture* texture = get(entry);
569
570    if (!texture) {
571        SkPath path;
572        SkRect r;
573        r.set(0.0f, 0.0f, width, height);
574        path.addRect(r, SkPath::kCW_Direction);
575
576        texture = addTexture(entry, &path, paint);
577    }
578
579    return texture;
580}
581
582///////////////////////////////////////////////////////////////////////////////
583// Arcs
584///////////////////////////////////////////////////////////////////////////////
585
586PathTexture* PathCache::getArc(float width, float height,
587        float startAngle, float sweepAngle, bool useCenter, SkPaint* paint) {
588    PathDescription entry(kShapeArc, paint);
589    entry.shape.arc.mWidth = width;
590    entry.shape.arc.mHeight = height;
591    entry.shape.arc.mStartAngle = startAngle;
592    entry.shape.arc.mSweepAngle = sweepAngle;
593    entry.shape.arc.mUseCenter = useCenter;
594
595    PathTexture* texture = get(entry);
596
597    if (!texture) {
598        SkPath path;
599        SkRect r;
600        r.set(0.0f, 0.0f, width, height);
601        if (useCenter) {
602            path.moveTo(r.centerX(), r.centerY());
603        }
604        path.arcTo(r, startAngle, sweepAngle, !useCenter);
605        if (useCenter) {
606            path.close();
607        }
608
609        texture = addTexture(entry, &path, paint);
610    }
611
612    return texture;
613}
614
615}; // namespace uirenderer
616}; // namespace android
617