Snapshot.h revision 079ba2c85b15e882629b8d188f5fbdb42f7f8eea
1/* 2 * Copyright (C) 2010 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_UI_SNAPSHOT_H 18#define ANDROID_UI_SNAPSHOT_H 19 20#include <GLES2/gl2.h> 21#include <GLES2/gl2ext.h> 22 23#include <utils/RefBase.h> 24 25#include <SkRegion.h> 26 27#include "Layer.h" 28#include "Matrix.h" 29#include "Rect.h" 30 31namespace android { 32namespace uirenderer { 33 34/** 35 * A snapshot holds information about the current state of the rendering 36 * surface. A snapshot is usually created whenever the user calls save() 37 * and discarded when the user calls restore(). Once a snapshot is created, 38 * it can hold information for deferred rendering. 39 * 40 * Each snapshot has a link to a previous snapshot, indicating the previous 41 * state of the renderer. 42 */ 43class Snapshot: public LightRefBase<Snapshot> { 44public: 45 Snapshot(): flags(0x0), previous(NULL), layer(NULL), fbo(0) { } 46 47 /** 48 * Copies the specified snapshot. Only the transform and clip rectangle 49 * are copied. The layer information is set to 0 and the transform is 50 * assumed to be dirty. The specified snapshot is stored as the previous 51 * snapshot. 52 */ 53 Snapshot(const sp<Snapshot> s): 54 height(s->height), 55 transform(s->transform), 56 clipRect(s->clipRect), 57 flags(0x0), 58 previous(s), 59 layer(NULL), 60 fbo(s->fbo) { 61 } 62 63 /** 64 * Various flags set on #flags. 65 */ 66 enum Flags { 67 /** 68 * Indicates that the clip region was modified. When this 69 * snapshot is restored so must the clip. 70 */ 71 kFlagClipSet = 0x1, 72 /** 73 * Indicates that this snapshot was created when saving 74 * a new layer. 75 */ 76 kFlagIsLayer = 0x2, 77 /** 78 * Indicates that this snapshot has changed the ortho matrix. 79 */ 80 kFlagDirtyOrtho = 0x4, 81 }; 82 83 /** 84 * Intersects the current clip with the new clip rectangle. 85 */ 86 bool clip(float left, float top, float right, float bottom, SkRegion::Op op) { 87 bool clipped = false; 88 89 Rect r(left, top, right, bottom); 90 transform.mapRect(r); 91 92 switch (op) { 93 case SkRegion::kDifference_Op: 94 break; 95 case SkRegion::kIntersect_Op: 96 clipped = clipRect.intersect(r); 97 break; 98 case SkRegion::kUnion_Op: 99 clipped = clipRect.unionWith(r); 100 break; 101 case SkRegion::kXOR_Op: 102 break; 103 case SkRegion::kReverseDifference_Op: 104 break; 105 case SkRegion::kReplace_Op: 106 clipRect.set(r); 107 clipped = true; 108 break; 109 } 110 111 if (clipped) { 112 flags |= Snapshot::kFlagClipSet; 113 } 114 115 return clipped; 116 } 117 118 /** 119 * Sets the current clip. 120 */ 121 void setClip(float left, float top, float right, float bottom) { 122 clipRect.set(left, top, right, bottom); 123 flags |= Snapshot::kFlagClipSet; 124 } 125 126 const Rect& getLocalClip() { 127 mat4 inverse; 128 inverse.loadInverse(transform); 129 localClip.set(clipRect); 130 inverse.mapRect(localClip); 131 return localClip; 132 } 133 134 /** 135 * Height of the framebuffer the snapshot is rendering into. 136 */ 137 int height; 138 139 /** 140 * Local transformation. Holds the current translation, scale and 141 * rotation values. 142 */ 143 mat4 transform; 144 145 /** 146 * Current clip region. The clip is stored in canvas-space coordinates, 147 * (screen-space coordinates in the regular case.) 148 */ 149 Rect clipRect; 150 151 /** 152 * Dirty flags. 153 */ 154 int flags; 155 156 /** 157 * Previous snapshot. 158 */ 159 sp<Snapshot> previous; 160 161 /** 162 * Only set when the flag kFlagIsLayer is set. 163 */ 164 Layer* layer; 165 GLuint fbo; 166 167 /** 168 * Contains the previous ortho matrix. 169 */ 170 mat4 orthoMatrix; 171 172private: 173 Rect localClip; 174 175}; // class Snapshot 176 177}; // namespace uirenderer 178}; // namespace android 179 180#endif // ANDROID_UI_SNAPSHOT_H 181