Merge "Add Bitmap.isPremultiplied()"
diff --git a/api/current.txt b/api/current.txt
index 8259286..17ab2e5 100644
--- a/api/current.txt
+++ b/api/current.txt
@@ -8121,6 +8121,7 @@
method public final int getWidth();
method public final boolean hasAlpha();
method public final boolean isMutable();
+ method public final boolean isPremultiplied();
method public final boolean isRecycled();
method public void prepareToDraw();
method public void recycle();
diff --git a/graphics/java/android/graphics/Bitmap.java b/graphics/java/android/graphics/Bitmap.java
index c726d0e..c91c2f1 100644
--- a/graphics/java/android/graphics/Bitmap.java
+++ b/graphics/java/android/graphics/Bitmap.java
@@ -27,7 +27,6 @@
import java.nio.ShortBuffer;
public final class Bitmap implements Parcelable {
-
/**
* Indicates that the bitmap was created for an unknown pixel density.
*
@@ -64,7 +63,7 @@
private boolean mRecycled;
// Package-scoped for fast access.
- /*package*/ int mDensity = sDefaultDensity = getDefaultDensity();
+ int mDensity = sDefaultDensity = getDefaultDensity();
private static volatile Matrix sScaleMatrix;
@@ -78,8 +77,8 @@
public static void setDefaultDensity(int density) {
sDefaultDensity = density;
}
-
- /*package*/ static int getDefaultDensity() {
+
+ static int getDefaultDensity() {
if (sDefaultDensity >= 0) {
return sDefaultDensity;
}
@@ -95,7 +94,7 @@
This can be called from JNI code.
*/
- /*package*/ Bitmap(int nativeBitmap, byte[] buffer, boolean isMutable, byte[] ninePatchChunk,
+ Bitmap(int nativeBitmap, byte[] buffer, boolean isMutable, byte[] ninePatchChunk,
int density) {
this(nativeBitmap, buffer, isMutable, ninePatchChunk, null, density);
}
@@ -108,7 +107,7 @@
This can be called from JNI code.
*/
- /*package*/ Bitmap(int nativeBitmap, byte[] buffer, boolean isMutable, byte[] ninePatchChunk,
+ Bitmap(int nativeBitmap, byte[] buffer, boolean isMutable, byte[] ninePatchChunk,
int[] layoutBounds, int density) {
if (nativeBitmap == 0) {
throw new RuntimeException("internal error: native bitmap is 0");
@@ -347,11 +346,15 @@
}
/**
- * Copy the bitmap's pixels into the specified buffer (allocated by the
+ * <p>Copy the bitmap's pixels into the specified buffer (allocated by the
* caller). An exception is thrown if the buffer is not large enough to
* hold all of the pixels (taking into account the number of bytes per
* pixel) or if the Buffer subclass is not one of the support types
- * (ByteBuffer, ShortBuffer, IntBuffer).
+ * (ByteBuffer, ShortBuffer, IntBuffer).</p>
+ * <p>The content of the bitmap is copied into the buffer as-is. This means
+ * that if this bitmap stores its pixels pre-multiplied
+ * (see {@link #isPremultiplied()}, the values in the buffer will also be
+ * pre-multiplied.</p>
*/
public void copyPixelsToBuffer(Buffer dst) {
int elements = dst.remaining();
@@ -382,10 +385,10 @@
}
/**
- * Copy the pixels from the buffer, beginning at the current position,
+ * <p>Copy the pixels from the buffer, beginning at the current position,
* overwriting the bitmap's pixels. The data in the buffer is not changed
* in any way (unlike setPixels(), which converts from unpremultipled 32bit
- * to whatever the bitmap's native format is.
+ * to whatever the bitmap's native format is.</p>
*/
public void copyPixelsFromBuffer(Buffer src) {
checkRecycled("copyPixelsFromBuffer called on recycled bitmap");
@@ -402,7 +405,7 @@
throw new RuntimeException("unsupported Buffer subclass");
}
- long bufferBytes = (long)elements << shift;
+ long bufferBytes = (long) elements << shift;
long bitmapBytes = getByteCount();
if (bufferBytes < bitmapBytes) {
@@ -780,6 +783,25 @@
return mIsMutable;
}
+ /**
+ * <p>Indicates whether pixels stored in this bitmaps are stored pre-multiplied.
+ * When a pixel is pre-multiplied, the RGB components have been multiplied by
+ * the alpha component. For instance, if the original color is a 50%
+ * translucent red <code>(128, 255, 0, 0)</code>, the pre-multiplied form is
+ * <code>(128, 128, 0, 0)</code>.</p>
+ *
+ * <p>This method always returns false if {@link #getConfig()} is
+ * {@link Bitmap.Config#ALPHA_8} or {@link Bitmap.Config#RGB_565}.</p>
+ *
+ * @return true if the underlying pixels have been pre-multiplied, false
+ * otherwise
+ */
+ public final boolean isPremultiplied() {
+ final Config config = getConfig();
+ //noinspection deprecation
+ return config == Config.ARGB_8888 || config == Config.ARGB_4444;
+ }
+
/** Returns the bitmap's width */
public final int getWidth() {
return mWidth == -1 ? mWidth = nativeWidth(mNativeBitmap) : mWidth;
@@ -926,7 +948,7 @@
/**
* Returns the {@link Color} at the specified location. Throws an exception
* if x or y are out of bounds (negative or >= to the width or height
- * respectively).
+ * respectively). The returned color is a non-premultiplied ARGB value.
*
* @param x The x coordinate (0...width-1) of the pixel to return
* @param y The y coordinate (0...height-1) of the pixel to return
@@ -944,6 +966,7 @@
* a packed int representing a {@link Color}. The stride parameter allows
* the caller to allow for gaps in the returned pixels array between
* rows. For normal packed results, just pass width for the stride value.
+ * The returned colors are non-premultiplied ARGB values.
*
* @param pixels The array to receive the bitmap's colors
* @param offset The first index to write into pixels[]
@@ -955,6 +978,7 @@
* the bitmap
* @param width The number of pixels to read from each row
* @param height The number of rows to read
+ *
* @throws IllegalArgumentException if x, y, width, height exceed the
* bounds of the bitmap, or if abs(stride) < width.
* @throws ArrayIndexOutOfBoundsException if the pixels array is too small
@@ -974,6 +998,7 @@
/**
* Shared code to check for illegal arguments passed to getPixel()
* or setPixel()
+ *
* @param x x coordinate of the pixel
* @param y y coordinate of the pixel
*/
@@ -1029,12 +1054,14 @@
}
/**
- * Write the specified {@link Color} into the bitmap (assuming it is
- * mutable) at the x,y coordinate.
+ * <p>Write the specified {@link Color} into the bitmap (assuming it is
+ * mutable) at the x,y coordinate. The color must be a
+ * non-premultiplied ARGB value.</p>
*
* @param x The x coordinate of the pixel to replace (0...width-1)
* @param y The y coordinate of the pixel to replace (0...height-1)
- * @param color The {@link Color} to write into the bitmap
+ * @param color The ARGB color to write into the bitmap
+ *
* @throws IllegalStateException if the bitmap is not mutable
* @throws IllegalArgumentException if x, y are outside of the bitmap's
* bounds.
@@ -1049,8 +1076,9 @@
}
/**
- * Replace pixels in the bitmap with the colors in the array. Each element
- * in the array is a packed int prepresenting a {@link Color}
+ * <p>Replace pixels in the bitmap with the colors in the array. Each element
+ * in the array is a packed int prepresenting a non-premultiplied ARGB
+ * {@link Color}.</p>
*
* @param pixels The colors to write to the bitmap
* @param offset The index of the first color to read from pixels[]
@@ -1063,6 +1091,7 @@
* the bitmap.
* @param width The number of colors to copy from pixels[] per row
* @param height The number of rows to write to the bitmap
+ *
* @throws IllegalStateException if the bitmap is not mutable
* @throws IllegalArgumentException if x, y, width, height are outside of
* the bitmap's bounds.
@@ -1070,7 +1099,7 @@
* to receive the specified number of pixels.
*/
public void setPixels(int[] pixels, int offset, int stride,
- int x, int y, int width, int height) {
+ int x, int y, int width, int height) {
checkRecycled("Can't call setPixels() on a recycled bitmap");
if (!isMutable()) {
throw new IllegalStateException();