GrLayerCache.cpp revision 9b14f26d0f3a974f3dd626c8354e1db1cfcd322f 
1/*
2 * Copyright 2014 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 "GrAtlas.h"
9#include "GrGpu.h"
10#include "GrLayerCache.h"
11
12/**
13 *  PictureLayerKey just wraps a saveLayer's id in the picture for GrTHashTable.
14 */
15class GrLayerCache::PictureLayerKey {
16public:
17    PictureLayerKey(uint32_t pictureID, int layerID)
18        : fPictureID(pictureID)
19        , fLayerID(layerID) {
20    }
21
22    uint32_t pictureID() const { return fPictureID; }
23    int layerID() const { return fLayerID; }
24
25    uint32_t getHash() const { return (fPictureID << 16) | fLayerID; }
26
27    static bool LessThan(const GrCachedLayer& layer, const PictureLayerKey& key) {
28        if (layer.pictureID() == key.pictureID()) {
29            return layer.layerID() < key.layerID();
30        }
31
32        return layer.pictureID() < key.pictureID();
33    }
34
35    static bool Equals(const GrCachedLayer& layer, const PictureLayerKey& key) {
36        return layer.pictureID() == key.pictureID() && layer.layerID() == key.layerID();
37    }
38
39private:
40    uint32_t fPictureID;
41    int      fLayerID;
42};
43
44GrLayerCache::GrLayerCache(GrGpu* gpu)
45    : fGpu(SkRef(gpu))
46    , fLayerPool(16) {      // TODO: may need to increase this later
47}
48
49GrLayerCache::~GrLayerCache() {
50}
51
52void GrLayerCache::init() {
53    static const int kAtlasTextureWidth = 1024;
54    static const int kAtlasTextureHeight = 1024;
55
56    SkASSERT(NULL == fAtlasMgr.get());
57
58    // The layer cache only gets 1 plot
59    SkISize textureSize = SkISize::Make(kAtlasTextureWidth, kAtlasTextureHeight);
60    fAtlasMgr.reset(SkNEW_ARGS(GrAtlasMgr, (fGpu, kSkia8888_GrPixelConfig,
61                                            textureSize, 1, 1, false)));
62}
63
64void GrLayerCache::freeAll() {
65    fLayerHash.deleteAll();
66    fAtlasMgr.free();
67}
68
69GrCachedLayer* GrLayerCache::createLayer(const SkPicture* picture, int layerID) {
70    GrCachedLayer* layer = fLayerPool.alloc();
71
72    SkASSERT(picture->uniqueID() != SK_InvalidGenID);
73    layer->init(picture->uniqueID(), layerID);
74    fLayerHash.insert(PictureLayerKey(picture->uniqueID(), layerID), layer);
75    return layer;
76}
77
78
79GrCachedLayer* GrLayerCache::findLayerOrCreate(const SkPicture* picture, int layerID) {
80    SkASSERT(picture->uniqueID() != SK_InvalidGenID);
81    GrCachedLayer* layer = fLayerHash.find(PictureLayerKey(picture->uniqueID(), layerID));
82    if (NULL == layer) {
83        layer = this->createLayer(picture, layerID);
84    }
85    return layer;
86}
87