FrameBuilder.h revision 975591a7af883d866d86ab819e164c6004694744 
1/*
2 * Copyright (C) 2016 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#pragma once
18
19#include "BakedOpState.h"
20#include "CanvasState.h"
21#include "DisplayList.h"
22#include "LayerBuilder.h"
23#include "RecordedOp.h"
24#include "utils/GLUtils.h"
25
26#include <vector>
27#include <unordered_map>
28
29struct SkRect;
30
31namespace android {
32namespace uirenderer {
33
34class BakedOpState;
35class LayerUpdateQueue;
36class OffscreenBuffer;
37class Rect;
38
39/**
40 * Traverses all of the drawing commands from the layers and RenderNodes passed into it, preparing
41 * them to be rendered.
42 *
43 * Resolves final drawing state for each operation (including clip, alpha and matrix), and then
44 * reorder and merge each op as it is resolved for drawing efficiency. Each layer of content (either
45 * from the LayerUpdateQueue, or temporary layers created by saveLayer operations in the
46 * draw stream) will create different reorder contexts, each in its own LayerBuilder.
47 *
48 * Then the prepared or 'baked' drawing commands can be issued by calling the templated
49 * replayBakedOps() function, which will dispatch them (including any created merged op collections)
50 * to a Dispatcher and Renderer. See BakedOpDispatcher for how these baked drawing operations are
51 * resolved into Glops and rendered via BakedOpRenderer.
52 *
53 * This class is also the authoritative source for traversing RenderNodes, both for standard op
54 * traversal within a DisplayList, and for out of order RenderNode traversal for Z and projection.
55 */
56class FrameBuilder : public CanvasStateClient {
57public:
58    FrameBuilder(const LayerUpdateQueue& layers, const SkRect& clip,
59            uint32_t viewportWidth, uint32_t viewportHeight,
60            const std::vector< sp<RenderNode> >& nodes, const Vector3& lightCenter);
61
62    virtual ~FrameBuilder() {}
63
64    /**
65     * replayBakedOps() is templated based on what class will receive ops being replayed.
66     *
67     * It constructs a lookup array of lambdas, which allows a recorded BakeOpState to use
68     * state->op->opId to lookup a receiver that will be called when the op is replayed.
69     *
70     */
71    template <typename StaticDispatcher, typename Renderer>
72    void replayBakedOps(Renderer& renderer) {
73        /**
74         * Defines a LUT of lambdas which allow a recorded BakedOpState to use state->op->opId to
75         * dispatch the op via a method on a static dispatcher when the op is replayed.
76         *
77         * For example a BitmapOp would resolve, via the lambda lookup, to calling:
78         *
79         * StaticDispatcher::onBitmapOp(Renderer& renderer, const BitmapOp& op, const BakedOpState& state);
80         */
81        #define X(Type) \
82                [](void* renderer, const BakedOpState& state) { \
83                    StaticDispatcher::on##Type(*(static_cast<Renderer*>(renderer)), \
84                            static_cast<const Type&>(*(state.op)), state); \
85                },
86        static BakedOpReceiver unmergedReceivers[] = BUILD_RENDERABLE_OP_LUT(X);
87        #undef X
88
89        /**
90         * Defines a LUT of lambdas which allow merged arrays of BakedOpState* to be passed to a
91         * static dispatcher when the group of merged ops is replayed.
92         */
93        #define X(Type) \
94                [](void* renderer, const MergedBakedOpList& opList) { \
95                    StaticDispatcher::onMerged##Type##s(*(static_cast<Renderer*>(renderer)), opList); \
96                },
97        static MergedOpReceiver mergedReceivers[] = BUILD_MERGEABLE_OP_LUT(X);
98        #undef X
99
100        // Relay through layers in reverse order, since layers
101        // later in the list will be drawn by earlier ones
102        for (int i = mLayerBuilders.size() - 1; i >= 1; i--) {
103            GL_CHECKPOINT(MODERATE);
104            LayerBuilder& layer = *(mLayerBuilders[i]);
105            if (layer.renderNode) {
106                // cached HW layer - can't skip layer if empty
107                renderer.startRepaintLayer(layer.offscreenBuffer, layer.repaintRect);
108                GL_CHECKPOINT(MODERATE);
109                layer.replayBakedOpsImpl((void*)&renderer, unmergedReceivers, mergedReceivers);
110                GL_CHECKPOINT(MODERATE);
111                renderer.endLayer();
112            } else if (!layer.empty()) { // save layer - skip entire layer if empty
113                layer.offscreenBuffer = renderer.startTemporaryLayer(layer.width, layer.height);
114                GL_CHECKPOINT(MODERATE);
115                layer.replayBakedOpsImpl((void*)&renderer, unmergedReceivers, mergedReceivers);
116                GL_CHECKPOINT(MODERATE);
117                renderer.endLayer();
118            }
119        }
120
121        GL_CHECKPOINT(MODERATE);
122        const LayerBuilder& fbo0 = *(mLayerBuilders[0]);
123        renderer.startFrame(fbo0.width, fbo0.height, fbo0.repaintRect);
124        GL_CHECKPOINT(MODERATE);
125        fbo0.replayBakedOpsImpl((void*)&renderer, unmergedReceivers, mergedReceivers);
126        GL_CHECKPOINT(MODERATE);
127        renderer.endFrame(fbo0.repaintRect);
128    }
129
130    void dump() const {
131        for (auto&& layer : mLayerBuilders) {
132            layer->dump();
133        }
134    }
135
136    ///////////////////////////////////////////////////////////////////
137    /// CanvasStateClient interface
138    ///////////////////////////////////////////////////////////////////
139    virtual void onViewportInitialized() override;
140    virtual void onSnapshotRestored(const Snapshot& removed, const Snapshot& restored) override;
141    virtual GLuint getTargetFbo() const override { return 0; }
142
143private:
144    enum class ChildrenSelectMode {
145        Negative,
146        Positive
147    };
148    void saveForLayer(uint32_t layerWidth, uint32_t layerHeight,
149            float contentTranslateX, float contentTranslateY,
150            const Rect& repaintRect,
151            const Vector3& lightCenter,
152            const BeginLayerOp* beginLayerOp, RenderNode* renderNode);
153    void restoreForLayer();
154
155    LayerBuilder& currentLayer() { return *(mLayerBuilders[mLayerStack.back()]); }
156
157    BakedOpState* tryBakeOpState(const RecordedOp& recordedOp) {
158        return BakedOpState::tryConstruct(mAllocator, *mCanvasState.writableSnapshot(), recordedOp);
159    }
160
161    // should always be surrounded by a save/restore pair, and not called if DisplayList is null
162    void deferNodePropsAndOps(RenderNode& node);
163
164    template <typename V>
165    void defer3dChildren(ChildrenSelectMode mode, const V& zTranslatedNodes);
166
167    void deferShadow(const RenderNodeOp& casterOp);
168
169    void deferProjectedChildren(const RenderNode& renderNode);
170
171    void deferNodeOps(const RenderNode& renderNode);
172
173    void deferRenderNodeOpImpl(const RenderNodeOp& op);
174
175    void replayBakedOpsImpl(void* arg, BakedOpReceiver* receivers);
176
177    SkPath* createFrameAllocatedPath() {
178        return mAllocator.create<SkPath>();
179    }
180
181    void deferStrokeableOp(const RecordedOp& op, batchid_t batchId,
182            BakedOpState::StrokeBehavior strokeBehavior = BakedOpState::StrokeBehavior::StyleDefined);
183
184    /**
185     * Declares all FrameBuilder::deferXXXXOp() methods for every RecordedOp type.
186     *
187     * These private methods are called from within deferImpl to defer each individual op
188     * type differently.
189     */
190#define X(Type) void defer##Type(const Type& op);
191    MAP_DEFERRABLE_OPS(X)
192#undef X
193
194    // List of every deferred layer's render state. Replayed in reverse order to render a frame.
195    std::vector<LayerBuilder*> mLayerBuilders;
196
197    /*
198     * Stack of indices within mLayerBuilders representing currently active layers. If drawing
199     * layerA within a layerB, will contain, in order:
200     *  - 0 (representing FBO 0, always present)
201     *  - layerB's index
202     *  - layerA's index
203     *
204     * Note that this doesn't vector doesn't always map onto all values of mLayerBuilders. When a
205     * layer is finished deferring, it will still be represented in mLayerBuilders, but it's index
206     * won't be in mLayerStack. This is because it can be replayed, but can't have any more drawing
207     * ops added to it.
208    */
209    std::vector<size_t> mLayerStack;
210
211    CanvasState mCanvasState;
212
213    // contains ResolvedOps and Batches
214    LinearAllocator mAllocator;
215};
216
217}; // namespace uirenderer
218}; // namespace android
219