1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
|
/* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
package org.mozilla.gecko.gfx;
import android.graphics.Rect;
import android.graphics.RectF;
import android.graphics.Region;
import org.mozilla.gecko.util.FloatUtils;
import java.nio.FloatBuffer;
import java.util.concurrent.locks.ReentrantLock;
public abstract class Layer {
private final ReentrantLock mTransactionLock;
private boolean mInTransaction;
private Rect mNewPosition;
private float mNewResolution;
protected Rect mPosition;
protected float mResolution;
protected boolean mUsesDefaultProgram = true;
public Layer() {
this(null);
}
public Layer(IntSize size) {
mTransactionLock = new ReentrantLock();
if (size == null) {
mPosition = new Rect();
} else {
mPosition = new Rect(0, 0, size.width, size.height);
}
mResolution = 1.0f;
}
/**
* Updates the layer. This returns false if there is still work to be done
* after this update.
*/
public final boolean update(RenderContext context) {
if (mTransactionLock.isHeldByCurrentThread()) {
throw new RuntimeException("draw() called while transaction lock held by this " +
"thread?!");
}
if (mTransactionLock.tryLock()) {
try {
performUpdates(context);
return true;
} finally {
mTransactionLock.unlock();
}
}
return false;
}
/** Subclasses override this function to draw the layer. */
public abstract void draw(RenderContext context);
/** Given the intrinsic size of the layer, returns the pixel boundaries of the layer rect. */
protected RectF getBounds(RenderContext context) {
return RectUtils.scale(new RectF(mPosition), context.zoomFactor / mResolution);
}
/**
* Returns the region of the layer that is considered valid. The default
* implementation of this will return the bounds of the layer, but this
* may be overridden.
*/
public Region getValidRegion(RenderContext context) {
return new Region(RectUtils.round(getBounds(context)));
}
/**
* Call this before modifying the layer. Note that, for TileLayers, "modifying the layer"
* includes altering the underlying CairoImage in any way. Thus you must call this function
* before modifying the byte buffer associated with this layer.
*
* This function may block, so you should never call this on the main UI thread.
*/
public void beginTransaction() {
if (mTransactionLock.isHeldByCurrentThread())
throw new RuntimeException("Nested transactions are not supported");
mTransactionLock.lock();
mInTransaction = true;
mNewResolution = mResolution;
}
/** Call this when you're done modifying the layer. */
public void endTransaction() {
if (!mInTransaction)
throw new RuntimeException("endTransaction() called outside a transaction");
mInTransaction = false;
mTransactionLock.unlock();
}
/** Returns true if the layer is currently in a transaction and false otherwise. */
protected boolean inTransaction() {
return mInTransaction;
}
/** Returns the current layer position. */
public Rect getPosition() {
return mPosition;
}
/** Sets the position. Only valid inside a transaction. */
public void setPosition(Rect newPosition) {
if (!mInTransaction)
throw new RuntimeException("setPosition() is only valid inside a transaction");
mNewPosition = newPosition;
}
/** Returns the current layer's resolution. */
public float getResolution() {
return mResolution;
}
/**
* Sets the layer resolution. This value is used to determine how many pixels per
* device pixel this layer was rendered at. This will be reflected by scaling by
* the reciprocal of the resolution in the layer's transform() function.
* Only valid inside a transaction. */
public void setResolution(float newResolution) {
if (!mInTransaction)
throw new RuntimeException("setResolution() is only valid inside a transaction");
mNewResolution = newResolution;
}
public boolean usesDefaultProgram() {
return mUsesDefaultProgram;
}
/**
* Subclasses may override this method to perform custom layer updates. This will be called
* with the transaction lock held. Subclass implementations of this method must call the
* superclass implementation. Returns false if there is still work to be done after this
* update is complete.
*/
protected void performUpdates(RenderContext context) {
if (mNewPosition != null) {
mPosition = mNewPosition;
mNewPosition = null;
}
if (mNewResolution != 0.0f) {
mResolution = mNewResolution;
mNewResolution = 0.0f;
}
}
/**
* This function fills in the provided <tt>dest</tt> array with values to render a texture.
* The array is filled with 4 sets of {x, y, z, texture_x, texture_y} values (so 20 values
* in total) corresponding to the corners of the rect.
*/
protected final void fillRectCoordBuffer(float[] dest, RectF rect, float viewWidth, float viewHeight,
Rect cropRect, float texWidth, float texHeight) {
//x, y, z, texture_x, texture_y
dest[0] = rect.left / viewWidth;
dest[1] = rect.bottom / viewHeight;
dest[2] = 0;
dest[3] = cropRect.left / texWidth;
dest[4] = cropRect.top / texHeight;
dest[5] = rect.left / viewWidth;
dest[6] = rect.top / viewHeight;
dest[7] = 0;
dest[8] = cropRect.left / texWidth;
dest[9] = cropRect.bottom / texHeight;
dest[10] = rect.right / viewWidth;
dest[11] = rect.bottom / viewHeight;
dest[12] = 0;
dest[13] = cropRect.right / texWidth;
dest[14] = cropRect.top / texHeight;
dest[15] = rect.right / viewWidth;
dest[16] = rect.top / viewHeight;
dest[17] = 0;
dest[18] = cropRect.right / texWidth;
dest[19] = cropRect.bottom / texHeight;
}
public static class RenderContext {
public final RectF viewport;
public final RectF pageRect;
public final float zoomFactor;
public final int positionHandle;
public final int textureHandle;
public final FloatBuffer coordBuffer;
public RenderContext(RectF aViewport, RectF aPageRect, float aZoomFactor,
int aPositionHandle, int aTextureHandle, FloatBuffer aCoordBuffer) {
viewport = aViewport;
pageRect = aPageRect;
zoomFactor = aZoomFactor;
positionHandle = aPositionHandle;
textureHandle = aTextureHandle;
coordBuffer = aCoordBuffer;
}
public boolean fuzzyEquals(RenderContext other) {
if (other == null) {
return false;
}
return RectUtils.fuzzyEquals(viewport, other.viewport)
&& RectUtils.fuzzyEquals(pageRect, other.pageRect)
&& FloatUtils.fuzzyEquals(zoomFactor, other.zoomFactor);
}
}
}
|
