am ef9fd18d: Merge change 8616 into donut

Merge commit 'ef9fd18d90829ecbd37769cc05a8d5288aff821c'

* commit 'ef9fd18d90829ecbd37769cc05a8d5288aff821c':
  Fiddle with default densities to try to sanitize the API.

2 files changed, 86 insertions, 31 deletions

diff --git a/graphics/java/android/graphics/Bitmap.java b/graphics/java/android/graphics/Bitmap.java
index bb19229..eef1096 100644
--- a/graphics/java/android/graphics/Bitmap.java
+++ b/graphics/java/android/graphics/Bitmap.java
@@ -46,10 +46,29 @@ public final class Bitmap implements Parcelable {
     private boolean mRecycled;
 
     // Package-scoped for fast access.
-    /*package*/ int mDensity = DENSITY_NONE;
+    /*package*/ int mDensity = sDefaultDensity = getDefaultDensity();
 
     private static volatile Matrix sScaleMatrix;
 
+    private static volatile int sDefaultDensity = -1;
+    
+    /**
+     * For backwards compatibility, allows the app layer to change the default
+     * density when running old apps.
+     * @hide
+     */
+    public static void setDefaultDensity(int density) {
+        sDefaultDensity = density;
+    }
+    
+    /*package*/ static int getDefaultDensity() {
+        if (sDefaultDensity >= 0) {
+            return sDefaultDensity;
+        }
+        sDefaultDensity = DisplayMetrics.DENSITY_DEVICE;
+        return sDefaultDensity;
+    }
+    
     /**
      * @noinspection UnusedDeclaration
      */
@@ -72,9 +91,16 @@ public final class Bitmap implements Parcelable {
     /**
      * <p>Returns the density for this bitmap.</p>
      *
-     * <p>The default density scale is {@link #DENSITY_NONE}.</p>
+     * <p>The default density is the same density as the current display,
+     * unless the current application does not support different screen
+     * densities in which case it is
+     * {@link android.util.DisplayMetrics#DENSITY_DEFAULT}.  Note that
+     * compatibility mode is determined by the application that was initially
+     * loaded into a process -- applications that share the same process should
+     * all have the same compatibility, or ensure they explicitly set the
+     * density of their bitmaps appropriately.</p>
      *
-     * @return A scaling factor of the default density (160) or {@link #DENSITY_NONE}
+     * @return A scaling factor of the default density or {@link #DENSITY_NONE}
      *         if the scaling factor is unknown.
      *
      * @see #setDensity(int)
@@ -272,7 +298,8 @@ public final class Bitmap implements Parcelable {
      * Tries to make a new bitmap based on the dimensions of this bitmap,
      * setting the new bitmap's config to the one specified, and then copying
      * this bitmap's pixels into the new bitmap. If the conversion is not
-     * supported, or the allocator fails, then this returns NULL.
+     * supported, or the allocator fails, then this returns NULL.  The returned
+     * bitmap initially has the same density as the original.
      *
      * @param config    The desired config for the resulting bitmap
      * @param isMutable True if the resulting bitmap should be mutable (i.e.
@@ -281,7 +308,11 @@ public final class Bitmap implements Parcelable {
      */
     public Bitmap copy(Config config, boolean isMutable) {
         checkRecycled("Can't copy a recycled bitmap");
-        return nativeCopy(mNativeBitmap, config.nativeInt, isMutable);
+        Bitmap b = nativeCopy(mNativeBitmap, config.nativeInt, isMutable);
+        if (b != null) {
+            b.mDensity = mDensity;
+        }
+        return b;
     }
 
     public static Bitmap createScaledBitmap(Bitmap src, int dstWidth,
@@ -316,7 +347,8 @@ public final class Bitmap implements Parcelable {
 
     /**
      * Returns an immutable bitmap from the source bitmap. The new bitmap may
-     * be the same object as source, or a copy may have been made.
+     * be the same object as source, or a copy may have been made.  It is
+     * initialized with the same density as the original bitmap.
      */
     public static Bitmap createBitmap(Bitmap src) {
         return createBitmap(src, 0, 0, src.getWidth(), src.getHeight());
@@ -325,7 +357,8 @@ public final class Bitmap implements Parcelable {
     /**
      * Returns an immutable bitmap from the specified subset of the source
      * bitmap. The new bitmap may be the same object as source, or a copy may
-     * have been made.
+     * have been made.  It is
+     * initialized with the same density as the original bitmap.
      *
      * @param source   The bitmap we are subsetting
      * @param x        The x coordinate of the first pixel in source
@@ -339,7 +372,8 @@ public final class Bitmap implements Parcelable {
 
     /**
      * Returns an immutable bitmap from subset of the source bitmap,
-     * transformed by the optional matrix.
+     * transformed by the optional matrix.  It is
+     * initialized with the same density as the original bitmap.
      *
      * @param source   The bitmap we are subsetting
      * @param x        The x coordinate of the first pixel in source
@@ -406,18 +440,20 @@ public final class Bitmap implements Parcelable {
                 paint.setAntiAlias(true);
             }
         }
-        canvas.setBitmap(bitmap);
-        canvas.drawBitmap(source, srcR, dstR, paint);
-
+        
         // The new bitmap was created from a known bitmap source so assume that
         // they use the same density
         bitmap.mDensity = source.mDensity;
+        
+        canvas.setBitmap(bitmap);
+        canvas.drawBitmap(source, srcR, dstR, paint);
 
         return bitmap;
     }
 
     /**
-     * Returns a mutable bitmap with the specified width and height.
+     * Returns a mutable bitmap with the specified width and height.  Its
+     * initial density is as per {@link #getDensity}.
      *
      * @param width    The width of the bitmap
      * @param height   The height of the bitmap
@@ -432,7 +468,8 @@ public final class Bitmap implements Parcelable {
 
     /**
      * Returns a immutable bitmap with the specified width and height, with each
-     * pixel value set to the corresponding value in the colors array.
+     * pixel value set to the corresponding value in the colors array.  Its
+     * initial density is as per {@link #getDensity}.
      *
      * @param colors   Array of {@link Color} used to initialize the pixels.
      * @param offset   Number of values to skip before the first color in the
@@ -466,7 +503,8 @@ public final class Bitmap implements Parcelable {
 
     /**
      * Returns a immutable bitmap with the specified width and height, with each
-     * pixel value set to the corresponding value in the colors array.
+     * pixel value set to the corresponding value in the colors array.  Its
+     * initial density is as per {@link #getDensity}.
      *
      * @param colors   Array of {@link Color} used to initialize the pixels.
      *                 This array must be at least as large as width * height.
@@ -882,6 +920,9 @@ public final class Bitmap implements Parcelable {
      * -2, -2, so that drawing the alpha bitmap offset by (-2, -2) and then
      * drawing the original would result in the blur visually aligning with
      * the original.
+     * 
+     * <p>The initial density of the returned bitmap is the same as the original's.
+     * 
      * @param paint Optional paint used to modify the alpha values in the
      *              resulting bitmap. Pass null for default behavior.
      * @param offsetXY Optional array that returns the X (index 0) and Y
@@ -899,6 +940,7 @@ public final class Bitmap implements Parcelable {
         if (bm == null) {
             throw new RuntimeException("Failed to extractAlpha on Bitmap");
         }
+        bm.mDensity = mDensity;
         return bm;
     }
 
diff --git a/graphics/java/android/graphics/Canvas.java b/graphics/java/android/graphics/Canvas.java
index 8ecbfbd..bc2e42e 100644
--- a/graphics/java/android/graphics/Canvas.java
+++ b/graphics/java/android/graphics/Canvas.java
@@ -49,7 +49,7 @@ public class Canvas {
     private DrawFilter  mDrawFilter;
 
     // Package-scoped for quick access.
-    /*package*/ int mDensity = DisplayMetrics.DENSITY_DEFAULT;
+    /*package*/ int mDensity = Bitmap.DENSITY_NONE;
     
     // Used by native code
     @SuppressWarnings({"UnusedDeclaration"})
@@ -57,7 +57,9 @@ public class Canvas {
 
     /**
      * Construct an empty raster canvas. Use setBitmap() to specify a bitmap to
-     * draw into.
+     * draw into.  The initial target density is {@link Bitmap#DENSITY_NONE};
+     * this will typically be replaced when a target bitmap is set for the
+     * canvas.
      */
     public Canvas() {
         // 0 means no native bitmap
@@ -67,6 +69,9 @@ public class Canvas {
     /**
      * Construct a canvas with the specified bitmap to draw into. The bitmap
      * must be mutable.
+     * 
+     * <p>The initial target density of the canvas is the same as the given
+     * bitmap's density.
      *
      * @param bitmap Specifies a mutable bitmap for the canvas to draw into.
      */
@@ -78,9 +83,7 @@ public class Canvas {
         throwIfRecycled(bitmap);
         mNativeCanvas = initRaster(bitmap.ni());
         mBitmap = bitmap;
-        final int density = bitmap.mDensity;
-        mDensity = density == Bitmap.DENSITY_NONE
-                ? DisplayMetrics.DENSITY_DEFAULT : density;
+        mDensity = bitmap.mDensity;
     }
     
     /*package*/ Canvas(int nativeCanvas) {
@@ -88,6 +91,7 @@ public class Canvas {
             throw new IllegalStateException();
         }
         mNativeCanvas = nativeCanvas;
+        mDensity = Bitmap.getDefaultDensity();
     }
     
     /**
@@ -96,10 +100,14 @@ public class Canvas {
      * be supported in this mode (e.g. some GL implementations may not support
      * antialiasing or certain effects like ColorMatrix or certain Xfermodes).
      * However, no exception will be thrown in those cases.
+     * 
+     * <p>The initial target density of the canvas is the same as the initial
+     * density of bitmaps as per {@link Bitmap#getDensity() Bitmap.getDensity()}.
      */
     public Canvas(GL gl) {
         mNativeCanvas = initGL();
         mGL = gl;
+        mDensity = Bitmap.getDefaultDensity();
     }
     
     /**
@@ -120,9 +128,13 @@ public class Canvas {
     }
         
     /**
-     * Specify a bitmap for the canvas to draw into.
+     * Specify a bitmap for the canvas to draw into.  As a side-effect, also
+     * updates the canvas's target density to match that of the bitmap.
      *
      * @param bitmap Specifies a mutable bitmap for the canvas to draw into.
+     * 
+     * @see #setDensity(int)
+     * @see #getDensity()
      */
     public void setBitmap(Bitmap bitmap) {
         if (!bitmap.isMutable()) {
@@ -135,9 +147,7 @@ public class Canvas {
 
         native_setBitmap(mNativeCanvas, bitmap.ni());
         mBitmap = bitmap;
-        final int density = bitmap.mDensity;
-        mDensity = density == Bitmap.DENSITY_NONE
-                ? DisplayMetrics.DENSITY_DEFAULT : density;
+        mDensity = bitmap.mDensity;
     }
     
     /**
@@ -176,12 +186,12 @@ public class Canvas {
     public native int getHeight();
 
     /**
-     * <p>Returns the density for this Canvas' backing bitmap.</p>
-     *
-     * <p>The default density scale is {@link Bitmap#DENSITY_NONE}.</p>
+     * <p>Returns the target density of the canvas.  The default density is
+     * derived from the density of its backing bitmap, or
+     * {@link Bitmap#DENSITY_NONE} if there is not one.</p>
      *
-     * @return A scaling factor of the default density (160dpi) or
-     *        {@link Bitmap#DENSITY_NONE} if the scaling factor is unknown.
+     * @return Returns the current target density of the canvas, which is used
+     * to determine the scaling factor when drawing a bitmap into it.
      *
      * @see #setDensity(int)
      * @see Bitmap#getDensity() 
@@ -191,10 +201,13 @@ public class Canvas {
     }
 
     /**
-     * <p>Specifies the density for this Canvas' backing bitmap.
+     * <p>Specifies the density for this Canvas' backing bitmap.  This modifies
+     * the target density of the canvas itself, as well as the density of its
+     * backing bitmap via {@link Bitmap#setDensity(int) Bitmap.setDensity(int)}.
      *
-     * @param density The density scaling factor to use with this bitmap or
-     *        {@link Bitmap#DENSITY_NONE} if the factor is unknown.
+     * @param density The new target density of the canvas, which is used
+     * to determine the scaling factor when drawing a bitmap into it.  Use
+     * {@link Bitmap#DENSITY_NONE} to disable bitmap scaling.
      *
      * @see #getDensity()
      * @see Bitmap#setDensity(int)