1 /*
2 * Copyright 2013 Google Inc.
3 *
4 * Use of this source code is governed by a BSD-style license that can be
5 * found in the LICENSE file.
6 */
7
8 #include "SkCachingPixelRef.h"
9 #include "SkBitmapCache.h"
10 #include "SkRect.h"
11
Install(SkImageGenerator * generator,SkBitmap * dst)12 bool SkCachingPixelRef::Install(SkImageGenerator* generator,
13 SkBitmap* dst) {
14 SkImageInfo info;
15 SkASSERT(dst != NULL);
16 if ((NULL == generator)
17 || !(generator->getInfo(&info))
18 || !dst->setInfo(info)) {
19 SkDELETE(generator);
20 return false;
21 }
22 SkAutoTUnref<SkCachingPixelRef> ref(SkNEW_ARGS(SkCachingPixelRef,
23 (info, generator, dst->rowBytes())));
24 dst->setPixelRef(ref);
25 return true;
26 }
27
SkCachingPixelRef(const SkImageInfo & info,SkImageGenerator * generator,size_t rowBytes)28 SkCachingPixelRef::SkCachingPixelRef(const SkImageInfo& info,
29 SkImageGenerator* generator,
30 size_t rowBytes)
31 : INHERITED(info)
32 , fImageGenerator(generator)
33 , fErrorInDecoding(false)
34 , fRowBytes(rowBytes) {
35 SkASSERT(fImageGenerator != NULL);
36 }
~SkCachingPixelRef()37 SkCachingPixelRef::~SkCachingPixelRef() {
38 SkDELETE(fImageGenerator);
39 // Assert always unlock before unref.
40 }
41
onNewLockPixels(LockRec * rec)42 bool SkCachingPixelRef::onNewLockPixels(LockRec* rec) {
43 if (fErrorInDecoding) {
44 return false; // don't try again.
45 }
46
47 const SkImageInfo& info = this->info();
48 if (!SkBitmapCache::Find(this->getGenerationID(),
49 SkIRect::MakeWH(info.width(), info.height()),
50 &fLockedBitmap)) {
51 // Cache has been purged, must re-decode.
52 if (!fLockedBitmap.tryAllocPixels(info, fRowBytes)) {
53 fErrorInDecoding = true;
54 return false;
55 }
56 if (!fImageGenerator->getPixels(info, fLockedBitmap.getPixels(), fRowBytes)) {
57 fErrorInDecoding = true;
58 return false;
59 }
60 fLockedBitmap.setImmutable();
61 SkBitmapCache::Add(this->getGenerationID(),
62 SkIRect::MakeWH(info.width(), info.height()),
63 fLockedBitmap);
64 }
65
66 // Now bitmap should contain a concrete PixelRef of the decoded image.
67 void* pixels = fLockedBitmap.getPixels();
68 SkASSERT(pixels != NULL);
69 rec->fPixels = pixels;
70 rec->fColorTable = NULL;
71 rec->fRowBytes = fLockedBitmap.rowBytes();
72 return true;
73 }
74
onUnlockPixels()75 void SkCachingPixelRef::onUnlockPixels() {
76 fLockedBitmap.reset();
77 }
78