diff options
Diffstat (limited to 'android/source/src/java/org/mozilla/gecko/gfx/Layer.java')
| -rw-r--r-- | android/source/src/java/org/mozilla/gecko/gfx/Layer.java | 218 |
1 files changed, 218 insertions, 0 deletions
diff --git a/android/source/src/java/org/mozilla/gecko/gfx/Layer.java b/android/source/src/java/org/mozilla/gecko/gfx/Layer.java new file mode 100644 index 000000000..b7fee29fc --- /dev/null +++ b/android/source/src/java/org/mozilla/gecko/gfx/Layer.java @@ -0,0 +1,218 @@ +/* -*- 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); + } + } +} + |