1f9a0a4306d589b4a4e20554fed512a603426bfa1Owen Lin/* 2f9a0a4306d589b4a4e20554fed512a603426bfa1Owen Lin * Copyright (C) 2010 The Android Open Source Project 3f9a0a4306d589b4a4e20554fed512a603426bfa1Owen Lin * 4f9a0a4306d589b4a4e20554fed512a603426bfa1Owen Lin * Licensed under the Apache License, Version 2.0 (the "License"); 5f9a0a4306d589b4a4e20554fed512a603426bfa1Owen Lin * you may not use this file except in compliance with the License. 6f9a0a4306d589b4a4e20554fed512a603426bfa1Owen Lin * You may obtain a copy of the License at 7f9a0a4306d589b4a4e20554fed512a603426bfa1Owen Lin * 8f9a0a4306d589b4a4e20554fed512a603426bfa1Owen Lin * http://www.apache.org/licenses/LICENSE-2.0 9f9a0a4306d589b4a4e20554fed512a603426bfa1Owen Lin * 10f9a0a4306d589b4a4e20554fed512a603426bfa1Owen Lin * Unless required by applicable law or agreed to in writing, software 11f9a0a4306d589b4a4e20554fed512a603426bfa1Owen Lin * distributed under the License is distributed on an "AS IS" BASIS, 12f9a0a4306d589b4a4e20554fed512a603426bfa1Owen Lin * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13f9a0a4306d589b4a4e20554fed512a603426bfa1Owen Lin * See the License for the specific language governing permissions and 14f9a0a4306d589b4a4e20554fed512a603426bfa1Owen Lin * limitations under the License. 15f9a0a4306d589b4a4e20554fed512a603426bfa1Owen Lin */ 16f9a0a4306d589b4a4e20554fed512a603426bfa1Owen Lin 17f9a0a4306d589b4a4e20554fed512a603426bfa1Owen Linpackage com.android.gallery3d.anim; 18f9a0a4306d589b4a4e20554fed512a603426bfa1Owen Lin 19f9a0a4306d589b4a4e20554fed512a603426bfa1Owen Linimport com.android.gallery3d.common.Utils; 20a4eae1abb4f2547dfbda84301ee764ce35464881John Reckimport com.android.gallery3d.glrenderer.GLCanvas; 21f9a0a4306d589b4a4e20554fed512a603426bfa1Owen Lin 22f9a0a4306d589b4a4e20554fed512a603426bfa1Owen Linpublic class AlphaAnimation extends CanvasAnimation { 23f9a0a4306d589b4a4e20554fed512a603426bfa1Owen Lin private final float mStartAlpha; 24f9a0a4306d589b4a4e20554fed512a603426bfa1Owen Lin private final float mEndAlpha; 25f9a0a4306d589b4a4e20554fed512a603426bfa1Owen Lin private float mCurrentAlpha; 26f9a0a4306d589b4a4e20554fed512a603426bfa1Owen Lin 27f9a0a4306d589b4a4e20554fed512a603426bfa1Owen Lin public AlphaAnimation(float from, float to) { 28f9a0a4306d589b4a4e20554fed512a603426bfa1Owen Lin mStartAlpha = from; 29f9a0a4306d589b4a4e20554fed512a603426bfa1Owen Lin mEndAlpha = to; 30f9a0a4306d589b4a4e20554fed512a603426bfa1Owen Lin mCurrentAlpha = from; 31f9a0a4306d589b4a4e20554fed512a603426bfa1Owen Lin } 32f9a0a4306d589b4a4e20554fed512a603426bfa1Owen Lin 33f9a0a4306d589b4a4e20554fed512a603426bfa1Owen Lin @Override 34f9a0a4306d589b4a4e20554fed512a603426bfa1Owen Lin public void apply(GLCanvas canvas) { 35f9a0a4306d589b4a4e20554fed512a603426bfa1Owen Lin canvas.multiplyAlpha(mCurrentAlpha); 36f9a0a4306d589b4a4e20554fed512a603426bfa1Owen Lin } 37f9a0a4306d589b4a4e20554fed512a603426bfa1Owen Lin 38f9a0a4306d589b4a4e20554fed512a603426bfa1Owen Lin @Override 39f9a0a4306d589b4a4e20554fed512a603426bfa1Owen Lin public int getCanvasSaveFlags() { 40f9a0a4306d589b4a4e20554fed512a603426bfa1Owen Lin return GLCanvas.SAVE_FLAG_ALPHA; 41f9a0a4306d589b4a4e20554fed512a603426bfa1Owen Lin } 42f9a0a4306d589b4a4e20554fed512a603426bfa1Owen Lin 43f9a0a4306d589b4a4e20554fed512a603426bfa1Owen Lin @Override 44f9a0a4306d589b4a4e20554fed512a603426bfa1Owen Lin protected void onCalculate(float progress) { 45f9a0a4306d589b4a4e20554fed512a603426bfa1Owen Lin mCurrentAlpha = Utils.clamp(mStartAlpha 46f9a0a4306d589b4a4e20554fed512a603426bfa1Owen Lin + (mEndAlpha - mStartAlpha) * progress, 0f, 1f); 47f9a0a4306d589b4a4e20554fed512a603426bfa1Owen Lin } 48f9a0a4306d589b4a4e20554fed512a603426bfa1Owen Lin} 49