src/com/android/launcher3/HolographicOutlineHelper.java - platform/packages/apps/Launcher3 - Git at Google

 /*
  * Copyright (C) 2008 The Android Open Source Project
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
  *      http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */

 package com.android.launcher3;

 import android.content.Context;
 import android.content.res.Resources;
 import android.graphics.Bitmap;
 import android.graphics.BlurMaskFilter;
 import android.graphics.Canvas;
 import android.graphics.Color;
 import android.graphics.Paint;
 import android.graphics.PorterDuff;
 import android.graphics.PorterDuffXfermode;
 import android.graphics.Rect;
 import android.graphics.drawable.Drawable;
 import android.util.SparseArray;

 /**
  * Utility class to generate shadow and outline effect, which are used for click feedback
  * and drag-n-drop respectively.
  */
 public class HolographicOutlineHelper {

     private static HolographicOutlineHelper sInstance;

     private final Canvas mCanvas = new Canvas();
     private final Paint mDrawPaint = new Paint(Paint.ANTI_ALIAS_FLAG | Paint.FILTER_BITMAP_FLAG);
     private final Paint mBlurPaint = new Paint(Paint.ANTI_ALIAS_FLAG | Paint.FILTER_BITMAP_FLAG);
     private final Paint mErasePaint = new Paint(Paint.ANTI_ALIAS_FLAG | Paint.FILTER_BITMAP_FLAG);

     private final BlurMaskFilter mMediumOuterBlurMaskFilter;
     private final BlurMaskFilter mThinOuterBlurMaskFilter;
     private final BlurMaskFilter mMediumInnerBlurMaskFilter;

     private final float mShadowBitmapShift;
     private final BlurMaskFilter mShadowBlurMaskFilter;

     // We have 4 different icon sizes: homescreen, hotseat, folder & all-apps
     private final SparseArray<Bitmap> mBitmapCache = new SparseArray<>(4);

     private HolographicOutlineHelper(Context context) {
         Resources res = context.getResources();

         float mediumBlur = res.getDimension(R.dimen.blur_size_medium_outline);
         mMediumOuterBlurMaskFilter = new BlurMaskFilter(mediumBlur, BlurMaskFilter.Blur.OUTER);
         mMediumInnerBlurMaskFilter = new BlurMaskFilter(mediumBlur, BlurMaskFilter.Blur.NORMAL);

         mThinOuterBlurMaskFilter = new BlurMaskFilter(
                 res.getDimension(R.dimen.blur_size_thin_outline), BlurMaskFilter.Blur.OUTER);

         mShadowBitmapShift = res.getDimension(R.dimen.blur_size_click_shadow);
         mShadowBlurMaskFilter = new BlurMaskFilter(mShadowBitmapShift, BlurMaskFilter.Blur.NORMAL);

         mErasePaint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.DST_OUT));
     }

     public static HolographicOutlineHelper obtain(Context context) {
         if (sInstance == null) {
             sInstance = new HolographicOutlineHelper(context);
         }
         return sInstance;
     }

     /**
      * Applies a more expensive and accurate outline to whatever is currently drawn in a specified
      * bitmap.
      */
     public void applyExpensiveOutlineWithBlur(Bitmap srcDst, Canvas srcDstCanvas, int color,
             int outlineColor) {
         applyExpensiveOutlineWithBlur(srcDst, srcDstCanvas, color, outlineColor, true);
     }

     public void applyExpensiveOutlineWithBlur(Bitmap srcDst, Canvas srcDstCanvas, int color,
             int outlineColor, boolean clipAlpha) {

         // We start by removing most of the alpha channel so as to ignore shadows, and
         // other types of partial transparency when defining the shape of the object
         if (clipAlpha) {
             int[] srcBuffer = new int[srcDst.getWidth() * srcDst.getHeight()];
             srcDst.getPixels(srcBuffer,
                     0, srcDst.getWidth(), 0, 0, srcDst.getWidth(), srcDst.getHeight());
             for (int i = 0; i < srcBuffer.length; i++) {
                 final int alpha = srcBuffer[i] >>> 24;
                 if (alpha < 188) {
                     srcBuffer[i] = 0;
                 }
             }
             srcDst.setPixels(srcBuffer,
                     0, srcDst.getWidth(), 0, 0, srcDst.getWidth(), srcDst.getHeight());
         }
         Bitmap glowShape = srcDst.extractAlpha();

         // calculate the outer blur first
         mBlurPaint.setMaskFilter(mMediumOuterBlurMaskFilter);
         int[] outerBlurOffset = new int[2];
         Bitmap thickOuterBlur = glowShape.extractAlpha(mBlurPaint, outerBlurOffset);

         mBlurPaint.setMaskFilter(mThinOuterBlurMaskFilter);
         int[] brightOutlineOffset = new int[2];
         Bitmap brightOutline = glowShape.extractAlpha(mBlurPaint, brightOutlineOffset);

         // calculate the inner blur
         srcDstCanvas.setBitmap(glowShape);
         srcDstCanvas.drawColor(0xFF000000, PorterDuff.Mode.SRC_OUT);
         mBlurPaint.setMaskFilter(mMediumInnerBlurMaskFilter);
         int[] thickInnerBlurOffset = new int[2];
         Bitmap thickInnerBlur = glowShape.extractAlpha(mBlurPaint, thickInnerBlurOffset);

         // mask out the inner blur
         srcDstCanvas.setBitmap(thickInnerBlur);
         srcDstCanvas.drawBitmap(glowShape, -thickInnerBlurOffset[0],
                 -thickInnerBlurOffset[1], mErasePaint);
         srcDstCanvas.drawRect(0, 0, -thickInnerBlurOffset[0], thickInnerBlur.getHeight(),
                 mErasePaint);
         srcDstCanvas.drawRect(0, 0, thickInnerBlur.getWidth(), -thickInnerBlurOffset[1],
                 mErasePaint);

         // draw the inner and outer blur
         srcDstCanvas.setBitmap(srcDst);
         srcDstCanvas.drawColor(0, PorterDuff.Mode.CLEAR);
         mDrawPaint.setColor(color);
         srcDstCanvas.drawBitmap(thickInnerBlur, thickInnerBlurOffset[0], thickInnerBlurOffset[1],
                 mDrawPaint);
         srcDstCanvas.drawBitmap(thickOuterBlur, outerBlurOffset[0], outerBlurOffset[1],
                 mDrawPaint);

         // draw the bright outline
         mDrawPaint.setColor(outlineColor);
         srcDstCanvas.drawBitmap(brightOutline, brightOutlineOffset[0], brightOutlineOffset[1],
                 mDrawPaint);

         // cleanup
         srcDstCanvas.setBitmap(null);
         brightOutline.recycle();
         thickOuterBlur.recycle();
         thickInnerBlur.recycle();
         glowShape.recycle();
     }

     Bitmap createMediumDropShadow(BubbleTextView view) {
         return createMediumDropShadow(view.getIcon(), view.getScaleX(), view.getScaleY(), true);
     }

     Bitmap createMediumDropShadow(Drawable drawable, boolean shouldCache) {
         return createMediumDropShadow(drawable, 1f, 1f, shouldCache);
     }

     Bitmap createMediumDropShadow(Drawable drawable, float scaleX, float scaleY,
                 boolean shouldCache) {
         if (drawable == null) {
             return null;
         }
         Rect rect = drawable.getBounds();

         int bitmapWidth = (int) (rect.width() * scaleX);
         int bitmapHeight = (int) (rect.height() * scaleY);
         if (bitmapHeight <= 0 || bitmapWidth <= 0) {
             return null;
         }

         int key = (bitmapWidth << 16) | bitmapHeight;
         Bitmap cache = shouldCache ? mBitmapCache.get(key) : null;
         if (cache == null) {
             cache = Bitmap.createBitmap(bitmapWidth, bitmapHeight, Bitmap.Config.ALPHA_8);
             mCanvas.setBitmap(cache);

             if (shouldCache) {
                 mBitmapCache.put(key, cache);
             }
         } else {
             mCanvas.setBitmap(cache);
             mCanvas.drawColor(Color.BLACK, PorterDuff.Mode.CLEAR);
         }

         int saveCount = mCanvas.save();
         mCanvas.scale(scaleX, scaleY);
         mCanvas.translate(-rect.left, -rect.top);
         drawable.draw(mCanvas);
         mCanvas.restoreToCount(saveCount);
         mCanvas.setBitmap(null);

         mBlurPaint.setMaskFilter(mShadowBlurMaskFilter);

         int extraSize = (int) (2 * mShadowBitmapShift);

         int resultWidth = bitmapWidth + extraSize;
         int resultHeight = bitmapHeight + extraSize;
         key = (resultWidth << 16) | resultHeight;
         Bitmap result = shouldCache ? mBitmapCache.get(key) : null;
         if (result == null) {
             result = Bitmap.createBitmap(resultWidth, resultHeight, Bitmap.Config.ALPHA_8);
             mCanvas.setBitmap(result);
         } else {
             // Use put instead of delete, to avoid unnecessary shrinking of cache array
             mBitmapCache.put(key, null);
             mCanvas.setBitmap(result);
             mCanvas.drawColor(Color.BLACK, PorterDuff.Mode.CLEAR);
         }
         mCanvas.drawBitmap(cache, mShadowBitmapShift, mShadowBitmapShift, mBlurPaint);
         mCanvas.setBitmap(null);
         return result;
     }

     public void recycleShadowBitmap(Bitmap bitmap) {
         if (bitmap != null) {
             mBitmapCache.put((bitmap.getWidth() << 16) | bitmap.getHeight(), bitmap);
         }
     }
 }
	/*
	* Copyright (C) 2008 The Android Open Source Project
	*
	* Licensed under the Apache License, Version 2.0 (the "License");
	* you may not use this file except in compliance with the License.
	* You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*/

	package com.android.launcher3;

	import android.content.Context;
	import android.content.res.Resources;
	import android.graphics.Bitmap;
	import android.graphics.BlurMaskFilter;
	import android.graphics.Canvas;
	import android.graphics.Color;
	import android.graphics.Paint;
	import android.graphics.PorterDuff;
	import android.graphics.PorterDuffXfermode;
	import android.graphics.Rect;
	import android.graphics.drawable.Drawable;
	import android.util.SparseArray;

	/**
	* Utility class to generate shadow and outline effect, which are used for click feedback
	* and drag-n-drop respectively.
	*/
	public class HolographicOutlineHelper {

	private static HolographicOutlineHelper sInstance;

	private final Canvas mCanvas = new Canvas();
	private final Paint mDrawPaint = new Paint(Paint.ANTI_ALIAS_FLAG \| Paint.FILTER_BITMAP_FLAG);
	private final Paint mBlurPaint = new Paint(Paint.ANTI_ALIAS_FLAG \| Paint.FILTER_BITMAP_FLAG);
	private final Paint mErasePaint = new Paint(Paint.ANTI_ALIAS_FLAG \| Paint.FILTER_BITMAP_FLAG);

	private final BlurMaskFilter mMediumOuterBlurMaskFilter;
	private final BlurMaskFilter mThinOuterBlurMaskFilter;
	private final BlurMaskFilter mMediumInnerBlurMaskFilter;

	private final float mShadowBitmapShift;
	private final BlurMaskFilter mShadowBlurMaskFilter;

	// We have 4 different icon sizes: homescreen, hotseat, folder & all-apps
	private final SparseArray<Bitmap> mBitmapCache = new SparseArray<>(4);

	private HolographicOutlineHelper(Context context) {
	Resources res = context.getResources();

	float mediumBlur = res.getDimension(R.dimen.blur_size_medium_outline);
	mMediumOuterBlurMaskFilter = new BlurMaskFilter(mediumBlur, BlurMaskFilter.Blur.OUTER);
	mMediumInnerBlurMaskFilter = new BlurMaskFilter(mediumBlur, BlurMaskFilter.Blur.NORMAL);

	mThinOuterBlurMaskFilter = new BlurMaskFilter(
	res.getDimension(R.dimen.blur_size_thin_outline), BlurMaskFilter.Blur.OUTER);

	mShadowBitmapShift = res.getDimension(R.dimen.blur_size_click_shadow);
	mShadowBlurMaskFilter = new BlurMaskFilter(mShadowBitmapShift, BlurMaskFilter.Blur.NORMAL);

	mErasePaint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.DST_OUT));
	}

	public static HolographicOutlineHelper obtain(Context context) {
	if (sInstance == null) {
	sInstance = new HolographicOutlineHelper(context);
	}
	return sInstance;
	}

	/**
	* Applies a more expensive and accurate outline to whatever is currently drawn in a specified
	* bitmap.
	*/
	public void applyExpensiveOutlineWithBlur(Bitmap srcDst, Canvas srcDstCanvas, int color,
	int outlineColor) {
	applyExpensiveOutlineWithBlur(srcDst, srcDstCanvas, color, outlineColor, true);
	}

	public void applyExpensiveOutlineWithBlur(Bitmap srcDst, Canvas srcDstCanvas, int color,
	int outlineColor, boolean clipAlpha) {

	// We start by removing most of the alpha channel so as to ignore shadows, and
	// other types of partial transparency when defining the shape of the object
	if (clipAlpha) {
	int[] srcBuffer = new int[srcDst.getWidth() * srcDst.getHeight()];
	srcDst.getPixels(srcBuffer,
	0, srcDst.getWidth(), 0, 0, srcDst.getWidth(), srcDst.getHeight());
	for (int i = 0; i < srcBuffer.length; i++) {
	final int alpha = srcBuffer[i] >>> 24;
	if (alpha < 188) {
	srcBuffer[i] = 0;
	}
	}
	srcDst.setPixels(srcBuffer,
	0, srcDst.getWidth(), 0, 0, srcDst.getWidth(), srcDst.getHeight());
	}
	Bitmap glowShape = srcDst.extractAlpha();

	// calculate the outer blur first
	mBlurPaint.setMaskFilter(mMediumOuterBlurMaskFilter);
	int[] outerBlurOffset = new int[2];
	Bitmap thickOuterBlur = glowShape.extractAlpha(mBlurPaint, outerBlurOffset);

	mBlurPaint.setMaskFilter(mThinOuterBlurMaskFilter);
	int[] brightOutlineOffset = new int[2];
	Bitmap brightOutline = glowShape.extractAlpha(mBlurPaint, brightOutlineOffset);

	// calculate the inner blur
	srcDstCanvas.setBitmap(glowShape);
	srcDstCanvas.drawColor(0xFF000000, PorterDuff.Mode.SRC_OUT);
	mBlurPaint.setMaskFilter(mMediumInnerBlurMaskFilter);
	int[] thickInnerBlurOffset = new int[2];
	Bitmap thickInnerBlur = glowShape.extractAlpha(mBlurPaint, thickInnerBlurOffset);

	// mask out the inner blur
	srcDstCanvas.setBitmap(thickInnerBlur);
	srcDstCanvas.drawBitmap(glowShape, -thickInnerBlurOffset[0],
	-thickInnerBlurOffset[1], mErasePaint);
	srcDstCanvas.drawRect(0, 0, -thickInnerBlurOffset[0], thickInnerBlur.getHeight(),
	mErasePaint);
	srcDstCanvas.drawRect(0, 0, thickInnerBlur.getWidth(), -thickInnerBlurOffset[1],
	mErasePaint);

	// draw the inner and outer blur
	srcDstCanvas.setBitmap(srcDst);
	srcDstCanvas.drawColor(0, PorterDuff.Mode.CLEAR);
	mDrawPaint.setColor(color);
	srcDstCanvas.drawBitmap(thickInnerBlur, thickInnerBlurOffset[0], thickInnerBlurOffset[1],
	mDrawPaint);
	srcDstCanvas.drawBitmap(thickOuterBlur, outerBlurOffset[0], outerBlurOffset[1],
	mDrawPaint);

	// draw the bright outline
	mDrawPaint.setColor(outlineColor);
	srcDstCanvas.drawBitmap(brightOutline, brightOutlineOffset[0], brightOutlineOffset[1],
	mDrawPaint);

	// cleanup
	srcDstCanvas.setBitmap(null);
	brightOutline.recycle();
	thickOuterBlur.recycle();
	thickInnerBlur.recycle();
	glowShape.recycle();
	}

	Bitmap createMediumDropShadow(BubbleTextView view) {
	return createMediumDropShadow(view.getIcon(), view.getScaleX(), view.getScaleY(), true);
	}

	Bitmap createMediumDropShadow(Drawable drawable, boolean shouldCache) {
	return createMediumDropShadow(drawable, 1f, 1f, shouldCache);
	}

	Bitmap createMediumDropShadow(Drawable drawable, float scaleX, float scaleY,
	boolean shouldCache) {
	if (drawable == null) {
	return null;
	}
	Rect rect = drawable.getBounds();

	int bitmapWidth = (int) (rect.width() * scaleX);
	int bitmapHeight = (int) (rect.height() * scaleY);
	if (bitmapHeight <= 0 \|\| bitmapWidth <= 0) {
	return null;
	}

	int key = (bitmapWidth << 16) \| bitmapHeight;
	Bitmap cache = shouldCache ? mBitmapCache.get(key) : null;
	if (cache == null) {
	cache = Bitmap.createBitmap(bitmapWidth, bitmapHeight, Bitmap.Config.ALPHA_8);
	mCanvas.setBitmap(cache);

	if (shouldCache) {
	mBitmapCache.put(key, cache);
	}
	} else {
	mCanvas.setBitmap(cache);
	mCanvas.drawColor(Color.BLACK, PorterDuff.Mode.CLEAR);
	}

	int saveCount = mCanvas.save();
	mCanvas.scale(scaleX, scaleY);
	mCanvas.translate(-rect.left, -rect.top);
	drawable.draw(mCanvas);
	mCanvas.restoreToCount(saveCount);
	mCanvas.setBitmap(null);

	mBlurPaint.setMaskFilter(mShadowBlurMaskFilter);

	int extraSize = (int) (2 * mShadowBitmapShift);

	int resultWidth = bitmapWidth + extraSize;
	int resultHeight = bitmapHeight + extraSize;
	key = (resultWidth << 16) \| resultHeight;
	Bitmap result = shouldCache ? mBitmapCache.get(key) : null;
	if (result == null) {
	result = Bitmap.createBitmap(resultWidth, resultHeight, Bitmap.Config.ALPHA_8);
	mCanvas.setBitmap(result);
	} else {
	// Use put instead of delete, to avoid unnecessary shrinking of cache array
	mBitmapCache.put(key, null);
	mCanvas.setBitmap(result);
	mCanvas.drawColor(Color.BLACK, PorterDuff.Mode.CLEAR);
	}
	mCanvas.drawBitmap(cache, mShadowBitmapShift, mShadowBitmapShift, mBlurPaint);
	mCanvas.setBitmap(null);
	return result;
	}

	public void recycleShadowBitmap(Bitmap bitmap) {
	if (bitmap != null) {
	mBitmapCache.put((bitmap.getWidth() << 16) \| bitmap.getHeight(), bitmap);
	}
	}
	}