The Tor Browser: mobile/android/base/gfx/SingleTileLayer.java@b8a032363ba2 (annotated)

mobile/android/base/gfx/SingleTileLayer.java@b8a032363ba2 (annotated)

mobile/android/base/gfx/SingleTileLayer.java

Thu, 22 Jan 2015 13:21:57 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Thu, 22 Jan 2015 13:21:57 +0100
branch: TOR_BUG_9701
changeset 15: b8a032363ba2
permissions: -rw-r--r--

Incorporate requested changes from Mozilla in review:
https://bugzilla.mozilla.org/show_bug.cgi?id=1123480#c6

 /* -*- 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 android.graphics.RegionIterator;
 import android.opengl.GLES20;
 import java.nio.FloatBuffer;
 /**
  * Encapsulates the logic needed to draw a single textured tile.
  *
  * TODO: Repeating textures really should be their own type of layer.
  */
 public class SingleTileLayer extends TileLayer {
     private static final String LOGTAG = "GeckoSingleTileLayer";
     private Rect mMask;
     // To avoid excessive GC, declare some objects here that would otherwise
     // be created and destroyed frequently during draw().
     private final RectF mBounds;
     private final RectF mTextureBounds;
     private final RectF mViewport;
     private final Rect mIntBounds;
     private final Rect mSubRect;
     private final RectF mSubRectF;
     private final Region mMaskedBounds;
     private final Rect mCropRect;
     private final RectF mObjRectF;
     private final float[] mCoords;
     public SingleTileLayer(CairoImage image) {
         this(false, image);
     }
     public SingleTileLayer(boolean repeat, CairoImage image) {
         this(image, repeat ? TileLayer.PaintMode.REPEAT : TileLayer.PaintMode.NORMAL);
     }
     public SingleTileLayer(CairoImage image, TileLayer.PaintMode paintMode) {
         super(image, paintMode);
         mBounds = new RectF();
         mTextureBounds = new RectF();
         mViewport = new RectF();
         mIntBounds = new Rect();
         mSubRect = new Rect();
         mSubRectF = new RectF();
         mMaskedBounds = new Region();
         mCropRect = new Rect();
         mObjRectF = new RectF();
         mCoords = new float[20];
     }
     /**
      * Set an area to mask out when rendering.
      */
     public void setMask(Rect aMaskRect) {
         mMask = aMaskRect;
     }
     @Override
     public void draw(RenderContext context) {
         // mTextureIDs may be null here during startup if Layer.java's draw method
         // failed to acquire the transaction lock and call performUpdates.
         if (!initialized())
             return;
         mViewport.set(context.viewport);
         if (repeats()) {
             // If we're repeating, we want to adjust the texture bounds so that
             // the texture repeats the correct number of times when drawn at
             // the size of the viewport.
             mBounds.set(getBounds(context));
             mTextureBounds.set(0.0f, 0.0f, mBounds.width(), mBounds.height());
             mBounds.set(0.0f, 0.0f, mViewport.width(), mViewport.height());
         } else if (stretches()) {
             // If we're stretching, we just want the bounds and texture bounds
             // to fit to the page.
             mBounds.set(context.pageRect);
             mTextureBounds.set(mBounds);
         } else {
             mBounds.set(getBounds(context));
             mTextureBounds.set(mBounds);
         }
         mBounds.roundOut(mIntBounds);
         mMaskedBounds.set(mIntBounds);
         if (mMask != null) {
             mMaskedBounds.op(mMask, Region.Op.DIFFERENCE);
             if (mMaskedBounds.isEmpty())
                 return;
         }
         // XXX Possible optimisation here, form this array so we can draw it in
         //     a single call.
         RegionIterator i = new RegionIterator(mMaskedBounds);
         while (i.next(mSubRect)) {
             // Compensate for rounding errors at the edge of the tile caused by
             // the roundOut above
             mSubRectF.set(Math.max(mBounds.left, (float)mSubRect.left),
                           Math.max(mBounds.top, (float)mSubRect.top),
                           Math.min(mBounds.right, (float)mSubRect.right),
                           Math.min(mBounds.bottom, (float)mSubRect.bottom));
             // This is the left/top/right/bottom of the rect, relative to the
             // bottom-left of the layer, to use for texture coordinates.
             mCropRect.set(Math.round(mSubRectF.left - mBounds.left),
                           Math.round(mBounds.bottom - mSubRectF.top),
                           Math.round(mSubRectF.right - mBounds.left),
                           Math.round(mBounds.bottom - mSubRectF.bottom));
             mObjRectF.set(mSubRectF.left - mViewport.left,
                           mViewport.bottom - mSubRectF.bottom,
                           mSubRectF.right - mViewport.left,
                           mViewport.bottom - mSubRectF.top);
             fillRectCoordBuffer(mCoords, mObjRectF, mViewport.width(), mViewport.height(),
                                 mCropRect, mTextureBounds.width(), mTextureBounds.height());
             FloatBuffer coordBuffer = context.coordBuffer;
             int positionHandle = context.positionHandle;
             int textureHandle = context.textureHandle;
             GLES20.glActiveTexture(GLES20.GL_TEXTURE0);
             GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, getTextureID());
             // Make sure we are at position zero in the buffer
             coordBuffer.position(0);
             coordBuffer.put(mCoords);
             // Unbind any the current array buffer so we can use client side buffers
             GLES20.glBindBuffer(GLES20.GL_ARRAY_BUFFER, 0);
             // Vertex coordinates are x,y,z starting at position 0 into the buffer.
             coordBuffer.position(0);
             GLES20.glVertexAttribPointer(positionHandle, 3, GLES20.GL_FLOAT, false, 20, coordBuffer);
             // Texture coordinates are texture_x, texture_y starting at position 3 into the buffer.
             coordBuffer.position(3);
             GLES20.glVertexAttribPointer(textureHandle, 2, GLES20.GL_FLOAT, false, 20, coordBuffer);
             GLES20.glDrawArrays(GLES20.GL_TRIANGLE_STRIP, 0, 4);
         }
     }
 }

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mobile/android/base/gfx/SingleTileLayer.java@b8a032363ba2 (annotated)

mobile/android/base/gfx/SingleTileLayer.java