1 /* 2 * Copyright (C) 2014 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 #ifndef ANDROID_HWUI_CANVAS_STATE_H 18 #define ANDROID_HWUI_CANVAS_STATE_H 19 20 #include <SkMatrix.h> 21 #include <SkPath.h> 22 #include <SkRegion.h> 23 24 #include "Snapshot.h" 25 26 namespace android { 27 namespace uirenderer { 28 29 /** 30 * Abstract base class for any class containing CanvasState. 31 * Defines three mandatory callbacks. 32 */ 33 class CanvasStateClient { 34 public: 35 CanvasStateClient() { } 36 virtual ~CanvasStateClient() { } 37 38 /** 39 * Callback allowing embedder to take actions in the middle of a 40 * setViewport() call. 41 */ 42 virtual void onViewportInitialized() = 0; 43 44 /** 45 * Callback allowing embedder to take actions in the middle of a 46 * restore() call. May be called several times sequentially. 47 */ 48 virtual void onSnapshotRestored(const Snapshot& removed, const Snapshot& restored) = 0; 49 50 /** 51 * Allows subclasses to control what value is stored in snapshot's 52 * fbo field in * initializeSaveStack. 53 */ 54 virtual GLuint getTargetFbo() const = 0; 55 56 }; // class CanvasStateClient 57 58 /** 59 * Implements Canvas state methods on behalf of Renderers. 60 * 61 * Manages the Snapshot stack, implementing matrix, save/restore, and clipping methods in the 62 * Renderer interface. Drawing and recording classes that include a CanvasState will have 63 * different use cases: 64 * 65 * Drawing code maintaining canvas state (i.e. OpenGLRenderer) can query attributes (such as 66 * transform) or hook into changes (e.g. save/restore) with minimal surface area for manipulating 67 * the stack itself. 68 * 69 * Recording code maintaining canvas state (i.e. DisplayListCanvas) can both record and pass 70 * through state operations to CanvasState, so that not only will querying operations work 71 * (getClip/Matrix), but so that quickRejection can also be used. 72 */ 73 74 class ANDROID_API CanvasState { 75 public: 76 CanvasState(CanvasStateClient& renderer); 77 ~CanvasState(); 78 79 /** 80 * Initializes the first snapshot, computing the projection matrix, 81 * and stores the dimensions of the render target. 82 */ 83 void initializeSaveStack(float clipLeft, float clipTop, float clipRight, float clipBottom, 84 const Vector3& lightCenter); 85 86 void setViewport(int width, int height); 87 88 bool hasRectToRectTransform() const { 89 return CC_LIKELY(currentTransform()->rectToRect()); 90 } 91 92 // Save (layer) 93 int getSaveCount() const { return mSaveCount; } 94 int save(int flags); 95 void restore(); 96 void restoreToCount(int saveCount); 97 98 // Save/Restore without side-effects 99 int saveSnapshot(int flags); 100 void restoreSnapshot(); 101 102 // Matrix 103 void getMatrix(SkMatrix* outMatrix) const; 104 void translate(float dx, float dy, float dz = 0.0f); 105 void rotate(float degrees); 106 void scale(float sx, float sy); 107 void skew(float sx, float sy); 108 109 void setMatrix(const SkMatrix& matrix); 110 void setMatrix(const Matrix4& matrix); // internal only convenience method 111 void concatMatrix(const SkMatrix& matrix); 112 void concatMatrix(const Matrix4& matrix); // internal only convenience method 113 114 // Clip 115 const Rect& getLocalClipBounds() const { return mSnapshot->getLocalClip(); } 116 const Rect& getRenderTargetClipBounds() const { return mSnapshot->getRenderTargetClip(); } 117 118 bool quickRejectConservative(float left, float top, float right, float bottom) const; 119 120 bool clipRect(float left, float top, float right, float bottom, SkRegion::Op op); 121 bool clipPath(const SkPath* path, SkRegion::Op op); 122 bool clipRegion(const SkRegion* region, SkRegion::Op op); 123 124 /** 125 * Sets a "clipping outline", which is independent from the regular clip. 126 * Currently only supports rectangles or rounded rectangles; passing in a 127 * more complicated outline fails silently. Replaces any previous clipping 128 * outline. 129 */ 130 void setClippingOutline(LinearAllocator& allocator, const Outline* outline); 131 void setClippingRoundRect(LinearAllocator& allocator, 132 const Rect& rect, float radius, bool highPriority = true); 133 void setProjectionPathMask(LinearAllocator& allocator, const SkPath* path); 134 135 /** 136 * Returns true if drawing in the rectangle (left, top, right, bottom) 137 * will be clipped out. Is conservative: might return false when subpixel- 138 * perfect tests would return true. 139 */ 140 bool calculateQuickRejectForScissor(float left, float top, float right, float bottom, 141 bool* clipRequired, bool* roundRectClipRequired, bool snapOut) const; 142 143 void setDirtyClip(bool opaque) { mDirtyClip = opaque; } 144 bool getDirtyClip() const { return mDirtyClip; } 145 146 void scaleAlpha(float alpha) { mSnapshot->alpha *= alpha; } 147 void setEmpty(bool value) { mSnapshot->empty = value; } 148 void setInvisible(bool value) { mSnapshot->invisible = value; } 149 150 inline const mat4* currentTransform() const { return currentSnapshot()->transform; } 151 inline const Rect& currentClipRect() const { return currentSnapshot()->getClipRect(); } 152 inline Region* currentRegion() const { return currentSnapshot()->region; } 153 inline int currentFlags() const { return currentSnapshot()->flags; } 154 const Vector3& currentLightCenter() const { return currentSnapshot()->getRelativeLightCenter(); } 155 inline bool currentlyIgnored() const { return currentSnapshot()->isIgnored(); } 156 int getViewportWidth() const { return currentSnapshot()->getViewportWidth(); } 157 int getViewportHeight() const { return currentSnapshot()->getViewportHeight(); } 158 int getWidth() const { return mWidth; } 159 int getHeight() const { return mHeight; } 160 bool clipIsSimple() const { return currentSnapshot()->clipIsSimple(); } 161 162 inline const Snapshot* currentSnapshot() const { 163 return mSnapshot != nullptr ? mSnapshot.get() : mFirstSnapshot.get(); 164 } 165 inline Snapshot* writableSnapshot() { return mSnapshot.get(); } 166 inline const Snapshot* firstSnapshot() const { return mFirstSnapshot.get(); } 167 168 private: 169 /// No default constructor - must supply a CanvasStateClient (mCanvas). 170 CanvasState(); 171 172 /// indicates that the clip has been changed since the last time it was consumed 173 bool mDirtyClip; 174 175 /// Dimensions of the drawing surface 176 int mWidth, mHeight; 177 178 /// Number of saved states 179 int mSaveCount; 180 181 /// Base state 182 sp<Snapshot> mFirstSnapshot; 183 184 /// Host providing callbacks 185 CanvasStateClient& mCanvas; 186 187 /// Current state 188 sp<Snapshot> mSnapshot; 189 190 }; // class CanvasState 191 192 }; // namespace uirenderer 193 }; // namespace android 194 195 #endif // ANDROID_HWUI_CANVAS_STATE_H 196
