SkMultiPictureDraw.cpp revision 96fcdcc219d2a0d3579719b84b28bede76efba64 
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 = new SkPaint(*paint);
39    } else {
40        fPaint = nullptr;
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        delete 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 (nullptr == canvas || nullptr == picture) {
72        SkDEBUGFAIL("parameters to SkMultiPictureDraw::add should be non-nullptr");
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
87//#define FORCE_SINGLE_THREAD_DRAWING_FOR_TESTING
88
89void SkMultiPictureDraw::draw(bool flush) {
90    AutoMPDReset mpdreset(this);
91
92#ifdef FORCE_SINGLE_THREAD_DRAWING_FOR_TESTING
93    for (int i = 0; i < fThreadSafeDrawData.count(); ++i) {
94        fThreadSafeDrawData[i].draw();
95    }
96#else
97    sk_parallel_for(fThreadSafeDrawData.count(), [&](int i) {
98        fThreadSafeDrawData[i].draw();
99    });
100#endif
101
102    // N.B. we could get going on any GPU work from this main thread while the CPU work runs.
103    // But in practice, we've either got GPU work or CPU work, not both.
104
105    const int count = fGPUDrawData.count();
106    if (0 == count) {
107        return;
108    }
109
110#if !defined(SK_IGNORE_GPU_LAYER_HOISTING) && SK_SUPPORT_GPU
111    GrContext* context = fGPUDrawData[0].fCanvas->getGrContext();
112    SkASSERT(context);
113
114    // Start by collecting all the layers that are going to be atlased and render
115    // them (if necessary). Hoisting the free floating layers is deferred until
116    // drawing the canvas that requires them.
117    SkTDArray<GrHoistedLayer> atlasedNeedRendering, atlasedRecycled;
118
119    for (int i = 0; i < count; ++i) {
120        const DrawData& data = fGPUDrawData[i];
121        // we only expect 1 context for all the canvases
122        SkASSERT(data.fCanvas->getGrContext() == context);
123
124        if (!data.fPaint) {
125            SkRect clipBounds;
126            if (!data.fCanvas->getClipBounds(&clipBounds)) {
127                continue;
128            }
129
130            SkMatrix initialMatrix = data.fCanvas->getTotalMatrix();
131            initialMatrix.preConcat(data.fMatrix);
132
133            GrRenderTarget* rt = data.fCanvas->internal_private_accessTopLayerRenderTarget();
134            SkASSERT(rt);
135
136            // TODO: sorting the cacheable layers from smallest to largest
137            // would improve the packing and reduce the number of swaps
138            // TODO: another optimization would be to make a first pass to
139            // lock any required layer that is already in the atlas
140            GrLayerHoister::FindLayersToAtlas(context, data.fPicture, initialMatrix,
141                                              clipBounds,
142                                              &atlasedNeedRendering, &atlasedRecycled,
143                                              rt->numColorSamples());
144        }
145    }
146
147    GrLayerHoister::DrawLayersToAtlas(context, atlasedNeedRendering);
148
149    SkTDArray<GrHoistedLayer> needRendering, recycled;
150#endif
151
152    for (int i = 0; i < count; ++i) {
153        const DrawData& data = fGPUDrawData[i];
154        SkCanvas* canvas = data.fCanvas;
155        const SkPicture* picture = data.fPicture;
156
157#if !defined(SK_IGNORE_GPU_LAYER_HOISTING) && SK_SUPPORT_GPU
158        if (!data.fPaint) {
159
160            SkRect clipBounds;
161            if (!canvas->getClipBounds(&clipBounds)) {
162                continue;
163            }
164
165            SkAutoCanvasMatrixPaint acmp(canvas, &data.fMatrix, data.fPaint, picture->cullRect());
166
167            const SkMatrix initialMatrix = canvas->getTotalMatrix();
168
169            GrRenderTarget* rt = data.fCanvas->internal_private_accessTopLayerRenderTarget();
170            SkASSERT(rt);
171
172            // Find the layers required by this canvas. It will return atlased
173            // layers in the 'recycled' list since they have already been drawn.
174            GrLayerHoister::FindLayersToHoist(context, picture, initialMatrix,
175                                              clipBounds, &needRendering, &recycled,
176                                              rt->numColorSamples());
177
178            GrLayerHoister::DrawLayers(context, needRendering);
179
180            // Render the entire picture using new layers
181            GrRecordReplaceDraw(picture, canvas, context->getLayerCache(),
182                                initialMatrix, nullptr);
183
184            GrLayerHoister::UnlockLayers(context, needRendering);
185            GrLayerHoister::UnlockLayers(context, recycled);
186
187            needRendering.rewind();
188            recycled.rewind();
189        } else
190#endif
191        {
192            canvas->drawPicture(picture, &data.fMatrix, data.fPaint);
193        }
194        if (flush) {
195            canvas->flush();
196        }
197    }
198
199#if !defined(SK_IGNORE_GPU_LAYER_HOISTING) && SK_SUPPORT_GPU
200    GrLayerHoister::UnlockLayers(context, atlasedNeedRendering);
201    GrLayerHoister::UnlockLayers(context, atlasedRecycled);
202#if !GR_CACHE_HOISTED_LAYERS
203    GrLayerHoister::PurgeCache(context);
204#endif
205#endif
206}
207
208