SkMultiPictureDraw.cpp revision e99d499caa7dbc80b58e0faf5ce137e7d30cc5d0 
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// Need to include something before #if SK_SUPPORT_GPU so that the Android
9// framework build, which gets its defines from SkTypes rather than a makefile,
10// has the definition before checking it.
11#include "SkCanvas.h"
12#include "SkCanvasPriv.h"
13#include "SkMultiPictureDraw.h"
14#include "SkPicture.h"
15#include "SkTaskGroup.h"
16
17#if SK_SUPPORT_GPU
18#include "GrContext.h"
19#include "GrLayerHoister.h"
20#include "GrRecordReplaceDraw.h"
21#include "GrRenderTarget.h"
22#endif
23
24void SkMultiPictureDraw::DrawData::draw() {
25    fCanvas->drawPicture(fPicture, &fMatrix, fPaint);
26}
27
28void SkMultiPictureDraw::DrawData::init(SkCanvas* canvas, const SkPicture* picture,
29                                        const SkMatrix* matrix, const SkPaint* paint) {
30    fPicture = SkRef(picture);
31    fCanvas = SkRef(canvas);
32    if (matrix) {
33        fMatrix = *matrix;
34    } else {
35        fMatrix.setIdentity();
36    }
37    if (paint) {
38        fPaint = SkNEW_ARGS(SkPaint, (*paint));
39    } else {
40        fPaint = NULL;
41    }
42}
43
44void SkMultiPictureDraw::DrawData::Reset(SkTDArray<DrawData>& data) {
45    for (int i = 0; i < data.count(); ++i) {
46        data[i].fPicture->unref();
47        data[i].fCanvas->unref();
48        SkDELETE(data[i].fPaint);
49    }
50    data.rewind();
51}
52
53//////////////////////////////////////////////////////////////////////////////////////
54
55SkMultiPictureDraw::SkMultiPictureDraw(int reserve) {
56    if (reserve > 0) {
57        fGPUDrawData.setReserve(reserve);
58        fThreadSafeDrawData.setReserve(reserve);
59    }
60}
61
62void SkMultiPictureDraw::reset() {
63    DrawData::Reset(fGPUDrawData);
64    DrawData::Reset(fThreadSafeDrawData);
65}
66
67void SkMultiPictureDraw::add(SkCanvas* canvas,
68                             const SkPicture* picture,
69                             const SkMatrix* matrix,
70                             const SkPaint* paint) {
71    if (NULL == canvas || NULL == picture) {
72        SkDEBUGFAIL("parameters to SkMultiPictureDraw::add should be non-NULL");
73        return;
74    }
75
76    SkTDArray<DrawData>& array = canvas->getGrContext() ? fGPUDrawData : fThreadSafeDrawData;
77    array.append()->init(canvas, picture, matrix, paint);
78}
79
80class AutoMPDReset : SkNoncopyable {
81    SkMultiPictureDraw* fMPD;
82public:
83    AutoMPDReset(SkMultiPictureDraw* mpd) : fMPD(mpd) {}
84    ~AutoMPDReset() { fMPD->reset(); }
85};
86
87void SkMultiPictureDraw::draw() {
88    AutoMPDReset mpdreset(this);
89    // we place the taskgroup after the MPDReset, to ensure that we don't delete the DrawData
90    // objects until after we're finished the tasks (which have pointers to the data).
91
92    SkTaskGroup group;
93    group.batch(DrawData::Draw, fThreadSafeDrawData.begin(), fThreadSafeDrawData.count());
94    // we deliberately don't call wait() here, since the destructor will do that, this allows us
95    // to continue processing gpu-data without having to wait on the cpu tasks.
96
97    const int count = fGPUDrawData.count();
98    if (0 == count) {
99        return;
100    }
101
102#if !defined(SK_IGNORE_GPU_LAYER_HOISTING) && SK_SUPPORT_GPU
103    GrContext* context = fGPUDrawData[0].fCanvas->getGrContext();
104    SkASSERT(context);
105
106    // Start by collecting all the layers that are going to be atlased and render
107    // them (if necessary). Hoisting the free floating layers is deferred until
108    // drawing the canvas that requires them.
109    SkTDArray<GrHoistedLayer> atlasedNeedRendering, atlasedRecycled;
110
111    for (int i = 0; i < count; ++i) {
112        const DrawData& data = fGPUDrawData[i];
113        // we only expect 1 context for all the canvases
114        SkASSERT(data.fCanvas->getGrContext() == context);
115
116        if (!data.fPaint) {
117            SkRect clipBounds;
118            if (!data.fCanvas->getClipBounds(&clipBounds)) {
119                continue;
120            }
121
122            SkMatrix initialMatrix = data.fCanvas->getTotalMatrix();
123            initialMatrix.preConcat(data.fMatrix);
124
125            GrRenderTarget* rt = data.fCanvas->internal_private_accessTopLayerRenderTarget();
126            SkASSERT(rt);
127
128            // TODO: sorting the cacheable layers from smallest to largest
129            // would improve the packing and reduce the number of swaps
130            // TODO: another optimization would be to make a first pass to
131            // lock any required layer that is already in the atlas
132            GrLayerHoister::FindLayersToAtlas(context, data.fPicture, initialMatrix,
133                                              clipBounds,
134                                              &atlasedNeedRendering, &atlasedRecycled,
135                                              rt->numSamples());
136        }
137    }
138
139    GrLayerHoister::DrawLayersToAtlas(context, atlasedNeedRendering);
140
141    SkTDArray<GrHoistedLayer> needRendering, recycled;
142#endif
143
144    for (int i = 0; i < count; ++i) {
145        const DrawData& data = fGPUDrawData[i];
146        SkCanvas* canvas = data.fCanvas;
147        const SkPicture* picture = data.fPicture;
148
149#if !defined(SK_IGNORE_GPU_LAYER_HOISTING) && SK_SUPPORT_GPU
150        if (!data.fPaint) {
151
152            SkRect clipBounds;
153            if (!canvas->getClipBounds(&clipBounds)) {
154                continue;
155            }
156
157            SkAutoCanvasMatrixPaint acmp(canvas, &data.fMatrix, data.fPaint, picture->cullRect());
158
159            const SkMatrix initialMatrix = canvas->getTotalMatrix();
160
161            GrRenderTarget* rt = data.fCanvas->internal_private_accessTopLayerRenderTarget();
162            SkASSERT(rt);
163
164            // Find the layers required by this canvas. It will return atlased
165            // layers in the 'recycled' list since they have already been drawn.
166            GrLayerHoister::FindLayersToHoist(context, picture, initialMatrix,
167                                              clipBounds, &needRendering, &recycled,
168                                              rt->numSamples());
169
170            GrLayerHoister::DrawLayers(context, needRendering);
171
172            // Render the entire picture using new layers
173            GrRecordReplaceDraw(picture, canvas, context->getLayerCache(),
174                                initialMatrix, NULL);
175
176            GrLayerHoister::UnlockLayers(context, needRendering);
177            GrLayerHoister::UnlockLayers(context, recycled);
178
179            needRendering.rewind();
180            recycled.rewind();
181        } else
182#endif
183        {
184            canvas->drawPicture(picture, &data.fMatrix, data.fPaint);
185        }
186    }
187
188#if !defined(SK_IGNORE_GPU_LAYER_HOISTING) && SK_SUPPORT_GPU
189    GrLayerHoister::UnlockLayers(context, atlasedNeedRendering);
190    GrLayerHoister::UnlockLayers(context, atlasedRecycled);
191#if !GR_CACHE_HOISTED_LAYERS
192    GrLayerHoister::PurgeCache(context);
193#endif
194#endif
195}
196
197