android/source/src/java/org/mozilla/gecko/gfx/TileLayer.java

   1 /* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
   2  * This Source Code Form is subject to the terms of the Mozilla Public
   3  * License, v. 2.0. If a copy of the MPL was not distributed with this
   4  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   5
   6 package org.mozilla.gecko.gfx;
   7
   8 import android.graphics.Rect;
   9 import android.opengl.GLES20;
  10 import android.util.Log;
  11
  12 import java.nio.ByteBuffer;
  13
  14 /**
  15  * Base class for tile layers, which encapsulate the logic needed to draw textured tiles in OpenGL
  16  * ES.
  17  */
  18 public abstract class TileLayer extends Layer {
  19     private static final String LOGTAG = "GeckoTileLayer";
  20
  21     private final Rect mDirtyRect;
  22     private IntSize mSize;
  23     private int[] mTextureIDs;
  24
  25     protected final CairoImage mImage;
  26
  27     public CairoImage getImage() {
  28         return mImage;
  29     }
  30
  31     public enum PaintMode { NORMAL, REPEAT, STRETCH };
  32     private PaintMode mPaintMode;
  33
  34     public TileLayer(CairoImage image, PaintMode paintMode) {
  35         super(image == null ? null : image.getSize());
  36
  37         mPaintMode = paintMode;
  38         mImage = image;
  39         mSize = new IntSize(0, 0);
  40         mDirtyRect = new Rect();
  41     }
  42
  43     protected boolean repeats() { return mPaintMode == PaintMode.REPEAT; }
  44     protected boolean stretches() { return mPaintMode == PaintMode.STRETCH; }
  45     protected int getTextureID() { return mTextureIDs[0]; }
  46     protected boolean initialized() { return mImage != null && mTextureIDs != null; }
  47
  48     @Override
  49     protected void finalize() throws Throwable {
  50         try {
  51             if (mTextureIDs != null)
  52                 TextureReaper.get().add(mTextureIDs);
  53         } finally {
  54             super.finalize();
  55         }
  56     }
  57
  58     public void destroy() {
  59         try {
  60             if (mImage != null) {
  61                 mImage.destroy();
  62             }
  63         } catch (Exception ex) {
  64             Log.e(LOGTAG, "error clearing buffers: ", ex);
  65         }
  66     }
  67
  68     public void setPaintMode(PaintMode mode) {
  69         mPaintMode = mode;
  70     }
  71
  72     /**
  73      * Invalidates the entire buffer so that it will be uploaded again. Only valid inside a
  74      * transaction.
  75      */
  76     public void invalidate() {
  77         if (!inTransaction())
  78             throw new RuntimeException("invalidate() is only valid inside a transaction");
  79         IntSize bufferSize = mImage.getSize();
  80         mDirtyRect.set(0, 0, bufferSize.width, bufferSize.height);
  81     }
  82
  83     private void validateTexture() {
  84         /* Calculate the ideal texture size. This must be a power of two if
  85          * the texture is repeated or OpenGL ES 2.0 isn't supported, as
  86          * OpenGL ES 2.0 is required for NPOT texture support (without
  87          * extensions), but doesn't support repeating NPOT textures.
  88          *
  89          * XXX Currently, we don't pick a GLES 2.0 context, so always round.
  90          */
  91         IntSize textureSize = mImage.getSize().nextPowerOfTwo();
  92
  93         if (!textureSize.equals(mSize)) {
  94             mSize = textureSize;
  95
  96             // Delete the old texture
  97             if (mTextureIDs != null) {
  98                 TextureReaper.get().add(mTextureIDs);
  99                 mTextureIDs = null;
 100
 101                 // Free the texture immediately, so we don't incur a
 102                 // temporarily increased memory usage.
 103                 TextureReaper.get().reap();
 104             }
 105         }
 106     }
 107
 108     @Override
 109     protected void performUpdates(RenderContext context) {
 110         super.performUpdates(context);
 111
 112         // Reallocate the texture if the size has changed
 113         validateTexture();
 114
 115         // Don't do any work if the image has an invalid size.
 116         if (!mImage.getSize().isPositive())
 117             return;
 118
 119         // If we haven't allocated a texture, assume the whole region is dirty
 120         if (mTextureIDs == null) {
 121             uploadFullTexture();
 122         } else {
 123             uploadDirtyRect(mDirtyRect);
 124         }
 125
 126         mDirtyRect.setEmpty();
 127     }
 128
 129     private void uploadFullTexture() {
 130         IntSize bufferSize = mImage.getSize();
 131         uploadDirtyRect(new Rect(0, 0, bufferSize.width, bufferSize.height));
 132     }
 133
 134     private void uploadDirtyRect(Rect dirtyRect) {
 135         // If we have nothing to upload, just return for now
 136         if (dirtyRect.isEmpty())
 137             return;
 138
 139         // It's possible that the buffer will be null, check for that and return
 140         ByteBuffer imageBuffer = mImage.getBuffer();
 141         if (imageBuffer == null)
 142             return;
 143
 144         if (mTextureIDs == null) {
 145             mTextureIDs = new int[1];
 146             GLES20.glGenTextures(mTextureIDs.length, mTextureIDs, 0);
 147         }
 148
 149         int cairoFormat = mImage.getFormat();
 150         CairoGLInfo glInfo = new CairoGLInfo(cairoFormat);
 151
 152         bindAndSetGLParameters();
 153
 154         // XXX TexSubImage2D is too broken to rely on Adreno, and very slow
 155         //     on other chipsets, so we always upload the entire buffer.
 156         IntSize bufferSize = mImage.getSize();
 157
 158         GLES20.glTexImage2D(GLES20.GL_TEXTURE_2D, 0, glInfo.internalFormat, mSize.width,
 159                             mSize.height, 0, glInfo.format, glInfo.type, imageBuffer);
 160
 161     }
 162
 163     private void bindAndSetGLParameters() {
 164         GLES20.glActiveTexture(GLES20.GL_TEXTURE0);
 165         GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, mTextureIDs[0]);
 166         GLES20.glTexParameterf(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_MIN_FILTER,
 167                                GLES20.GL_LINEAR);
 168         GLES20.glTexParameterf(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_MAG_FILTER,
 169                                GLES20.GL_LINEAR);
 170
 171         int repeatMode = repeats() ? GLES20.GL_REPEAT : GLES20.GL_CLAMP_TO_EDGE;
 172         GLES20.glTexParameterf(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_WRAP_S, repeatMode);
 173         GLES20.glTexParameterf(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_WRAP_T, repeatMode);
 174     }
 175 }
 176