supporting swipable home screens on xlarge devices

- icons and widgets on home screens can be "dimmed"
- celllayout no longer renders a dimmed version of itself, but instead its children make dimmed versions of themselves
- celllayout no longer always takes up full size of workspace, in landscape mode 
neighboring screens (celllayouts) are visible
- on xlarge devices, in landscape mode side screens are "dimmed"
- moved holographic outline helper to its own file
- fixed bug where mini-screens were still able to scroll left/right

Change-Id: I9e85ab4147edfae1e7525c3d11d42be3fabf4f6d

src/com/android/launcher2/PagedViewIcon.java

@@ -16,120 +16,25 @@
 
 package com.android.launcher2;
 
+import com.android.launcher2.PagedView.PagedViewIconCache;
+
 import android.content.Context;
 import android.content.pm.PackageManager;
 import android.content.pm.ResolveInfo;
 import android.content.res.Resources;
 import android.graphics.Bitmap;
-import android.graphics.BlurMaskFilter;
 import android.graphics.Canvas;
-import android.graphics.Matrix;
 import android.graphics.Paint;
 import android.graphics.PointF;
-import android.graphics.PorterDuff;
-import android.graphics.PorterDuffXfermode;
 import android.graphics.Rect;
 import android.graphics.Region.Op;
 import android.graphics.drawable.Drawable;
 import android.util.AttributeSet;
 import android.util.DisplayMetrics;
-import android.util.Log;
 import android.widget.Checkable;
 import android.widget.TextView;
 
-import com.android.launcher2.PagedView.PagedViewIconCache;
 
-class HolographicOutlineHelper {
-    private float mDensity;
-    private final Paint mHolographicPaint = new Paint();
-    private final Paint mBlurPaint = new Paint();
-    private final Paint mErasePaint = new Paint();
-    private static final Matrix mIdentity = new Matrix();;
-    private static final float BLUR_FACTOR = 3.5f;
-
-    public static final float DEFAULT_STROKE_WIDTH = 6.0f;
-    public static final int HOLOGRAPHIC_BLUE = 0xFF6699FF;
-    public static final int HOLOGRAPHIC_GREEN = 0xFF51E633;
-
-    HolographicOutlineHelper(float density) {
-        mDensity = density;
-        mHolographicPaint.setColor(HOLOGRAPHIC_BLUE);
-        mHolographicPaint.setFilterBitmap(true);
-        mHolographicPaint.setAntiAlias(true);
-        mBlurPaint.setMaskFilter(new BlurMaskFilter(BLUR_FACTOR * density, 
-                BlurMaskFilter.Blur.OUTER));
-        mBlurPaint.setFilterBitmap(true);
-        mErasePaint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.DST_OUT));
-        mErasePaint.setFilterBitmap(true);
-        mErasePaint.setAntiAlias(true);
-    }
-
-    private float cubic(float r) {
-        return (float) (Math.pow(r-1, 3) + 1);
-    }
-
-    /**
-     * Returns the interpolated holographic highlight alpha for the effect we want when scrolling 
-     * pages.
-     */
-    public float highlightAlphaInterpolator(float r) {
-        final float pivot = 0.3f;
-        if (r < pivot) {
-            return Math.max(0.5f, 0.65f*cubic(r/pivot));
-        } else {
-            return Math.min(1.0f, 0.65f*cubic(1 - (r-pivot)/(1-pivot)));
-        }
-    }
-
-    /**
-     * Returns the interpolated view alpha for the effect we want when scrolling pages.
-     */
-    public float viewAlphaInterpolator(float r) {
-        final float pivot = 0.6f;
-        if (r < pivot) {
-            return r/pivot;
-        } else {
-            return 1.0f;
-        }
-    }
-
-    /**
-     * Sets the color of the holographic paint to be used when applying the outline/blur.
-     */
-    void setColor(int color) {
-        mHolographicPaint.setColor(color);
-    }
-
-    /**
-     * Applies an outline to whatever is currently drawn in the specified bitmap.
-     */
-    void applyOutline(Bitmap srcDst, Canvas srcDstCanvas, float strokeWidth, PointF offset) {
-        strokeWidth *= mDensity;
-        Bitmap mask = srcDst.extractAlpha();
-        Matrix m = new Matrix();
-        final int width = srcDst.getWidth();
-        final int height = srcDst.getHeight();
-        float xScale = strokeWidth*2.0f/width;
-        float yScale = strokeWidth*2.0f/height;
-        m.preScale(1+xScale, 1+yScale, (width / 2.0f) + offset.x,
-                (height / 2.0f) + offset.y);
-
-        srcDstCanvas.drawColor(0, PorterDuff.Mode.CLEAR);
-        srcDstCanvas.drawBitmap(mask, m, mHolographicPaint);
-        srcDstCanvas.drawBitmap(mask, mIdentity, mErasePaint);
-        mask.recycle();
-    }
-
-    /**
-     * Applies an blur to whatever is currently drawn in the specified bitmap.
-     */
-    void applyBlur(Bitmap srcDst, Canvas srcDstCanvas) {
-        int[] xy = new int[2];
-        Bitmap mask = srcDst.extractAlpha(mBlurPaint, xy);
-        srcDstCanvas.drawBitmap(mask, xy[0], xy[1], mHolographicPaint);
-        mask.recycle();
-    }
-}
 
 /**
  * An icon on a PagedView, specifically for items in the launcher's paged view (with compound