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Diffstat (limited to 'src/com/android/gallery3d/ui/EdgeEffect.java')
| -rw-r--r-- | src/com/android/gallery3d/ui/EdgeEffect.java | 443 |
1 files changed, 0 insertions, 443 deletions
diff --git a/src/com/android/gallery3d/ui/EdgeEffect.java b/src/com/android/gallery3d/ui/EdgeEffect.java deleted file mode 100644 index 87ff0c5d3..000000000 --- a/src/com/android/gallery3d/ui/EdgeEffect.java +++ /dev/null @@ -1,443 +0,0 @@ -/* - * Copyright (C) 2011 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.gallery3d.ui; - -import android.content.Context; -import android.graphics.Canvas; -import android.graphics.Rect; -import android.view.animation.DecelerateInterpolator; -import android.view.animation.Interpolator; - -import com.android.gallery3d.R; -import com.android.gallery3d.glrenderer.GLCanvas; -import com.android.gallery3d.glrenderer.ResourceTexture; - -// This is copied from android.widget.EdgeEffect with some small modifications: -// (1) Copy the images (overscroll_{edge|glow}.png) to local resources. -// (2) Use "GLCanvas" instead of "Canvas" for draw()'s parameter. -// (3) Use a private Drawable class (which inherits from ResourceTexture) -// instead of android.graphics.drawable.Drawable to hold the images. -// The private Drawable class is used to translate original Canvas calls to -// corresponding GLCanvas calls. - -/** - * This class performs the graphical effect used at the edges of scrollable widgets - * when the user scrolls beyond the content bounds in 2D space. - * - * <p>EdgeEffect is stateful. Custom widgets using EdgeEffect should create an - * instance for each edge that should show the effect, feed it input data using - * the methods {@link #onAbsorb(int)}, {@link #onPull(float)}, and {@link #onRelease()}, - * and draw the effect using {@link #draw(Canvas)} in the widget's overridden - * {@link android.view.View#draw(Canvas)} method. If {@link #isFinished()} returns - * false after drawing, the edge effect's animation is not yet complete and the widget - * should schedule another drawing pass to continue the animation.</p> - * - * <p>When drawing, widgets should draw their main content and child views first, - * usually by invoking <code>super.draw(canvas)</code> from an overridden <code>draw</code> - * method. (This will invoke onDraw and dispatch drawing to child views as needed.) - * The edge effect may then be drawn on top of the view's content using the - * {@link #draw(Canvas)} method.</p> - */ -public class EdgeEffect { - @SuppressWarnings("unused") - private static final String TAG = "EdgeEffect"; - - // Time it will take the effect to fully recede in ms - private static final int RECEDE_TIME = 1000; - - // Time it will take before a pulled glow begins receding in ms - private static final int PULL_TIME = 167; - - // Time it will take in ms for a pulled glow to decay to partial strength before release - private static final int PULL_DECAY_TIME = 1000; - - private static final float MAX_ALPHA = 0.8f; - private static final float HELD_EDGE_ALPHA = 0.7f; - private static final float HELD_EDGE_SCALE_Y = 0.5f; - private static final float HELD_GLOW_ALPHA = 0.5f; - private static final float HELD_GLOW_SCALE_Y = 0.5f; - - private static final float MAX_GLOW_HEIGHT = 4.f; - - private static final float PULL_GLOW_BEGIN = 1.f; - private static final float PULL_EDGE_BEGIN = 0.6f; - - // Minimum velocity that will be absorbed - private static final int MIN_VELOCITY = 100; - - private static final float EPSILON = 0.001f; - - private final Drawable mEdge; - private final Drawable mGlow; - private int mWidth; - private int mHeight; - private final int MIN_WIDTH = 300; - private final int mMinWidth; - - private float mEdgeAlpha; - private float mEdgeScaleY; - private float mGlowAlpha; - private float mGlowScaleY; - - private float mEdgeAlphaStart; - private float mEdgeAlphaFinish; - private float mEdgeScaleYStart; - private float mEdgeScaleYFinish; - private float mGlowAlphaStart; - private float mGlowAlphaFinish; - private float mGlowScaleYStart; - private float mGlowScaleYFinish; - - private long mStartTime; - private float mDuration; - - private final Interpolator mInterpolator; - - private static final int STATE_IDLE = 0; - private static final int STATE_PULL = 1; - private static final int STATE_ABSORB = 2; - private static final int STATE_RECEDE = 3; - private static final int STATE_PULL_DECAY = 4; - - // How much dragging should effect the height of the edge image. - // Number determined by user testing. - private static final int PULL_DISTANCE_EDGE_FACTOR = 7; - - // How much dragging should effect the height of the glow image. - // Number determined by user testing. - private static final int PULL_DISTANCE_GLOW_FACTOR = 7; - private static final float PULL_DISTANCE_ALPHA_GLOW_FACTOR = 1.1f; - - private static final int VELOCITY_EDGE_FACTOR = 8; - private static final int VELOCITY_GLOW_FACTOR = 16; - - private int mState = STATE_IDLE; - - private float mPullDistance; - - /** - * Construct a new EdgeEffect with a theme appropriate for the provided context. - * @param context Context used to provide theming and resource information for the EdgeEffect - */ - public EdgeEffect(Context context) { - mEdge = new Drawable(context, R.drawable.overscroll_edge); - mGlow = new Drawable(context, R.drawable.overscroll_glow); - - mMinWidth = (int) (context.getResources().getDisplayMetrics().density * MIN_WIDTH + 0.5f); - mInterpolator = new DecelerateInterpolator(); - } - - /** - * Set the size of this edge effect in pixels. - * - * @param width Effect width in pixels - * @param height Effect height in pixels - */ - public void setSize(int width, int height) { - mWidth = width; - mHeight = height; - } - - /** - * Reports if this EdgeEffect's animation is finished. If this method returns false - * after a call to {@link #draw(Canvas)} the host widget should schedule another - * drawing pass to continue the animation. - * - * @return true if animation is finished, false if drawing should continue on the next frame. - */ - public boolean isFinished() { - return mState == STATE_IDLE; - } - - /** - * Immediately finish the current animation. - * After this call {@link #isFinished()} will return true. - */ - public void finish() { - mState = STATE_IDLE; - } - - /** - * A view should call this when content is pulled away from an edge by the user. - * This will update the state of the current visual effect and its associated animation. - * The host view should always {@link android.view.View#invalidate()} after this - * and draw the results accordingly. - * - * @param deltaDistance Change in distance since the last call. Values may be 0 (no change) to - * 1.f (full length of the view) or negative values to express change - * back toward the edge reached to initiate the effect. - */ - public void onPull(float deltaDistance) { - final long now = AnimationTime.get(); - if (mState == STATE_PULL_DECAY && now - mStartTime < mDuration) { - return; - } - if (mState != STATE_PULL) { - mGlowScaleY = PULL_GLOW_BEGIN; - } - mState = STATE_PULL; - - mStartTime = now; - mDuration = PULL_TIME; - - mPullDistance += deltaDistance; - float distance = Math.abs(mPullDistance); - - mEdgeAlpha = mEdgeAlphaStart = Math.max(PULL_EDGE_BEGIN, Math.min(distance, MAX_ALPHA)); - mEdgeScaleY = mEdgeScaleYStart = Math.max( - HELD_EDGE_SCALE_Y, Math.min(distance * PULL_DISTANCE_EDGE_FACTOR, 1.f)); - - mGlowAlpha = mGlowAlphaStart = Math.min(MAX_ALPHA, - mGlowAlpha + - (Math.abs(deltaDistance) * PULL_DISTANCE_ALPHA_GLOW_FACTOR)); - - float glowChange = Math.abs(deltaDistance); - if (deltaDistance > 0 && mPullDistance < 0) { - glowChange = -glowChange; - } - if (mPullDistance == 0) { - mGlowScaleY = 0; - } - - // Do not allow glow to get larger than MAX_GLOW_HEIGHT. - mGlowScaleY = mGlowScaleYStart = Math.min(MAX_GLOW_HEIGHT, Math.max( - 0, mGlowScaleY + glowChange * PULL_DISTANCE_GLOW_FACTOR)); - - mEdgeAlphaFinish = mEdgeAlpha; - mEdgeScaleYFinish = mEdgeScaleY; - mGlowAlphaFinish = mGlowAlpha; - mGlowScaleYFinish = mGlowScaleY; - } - - /** - * Call when the object is released after being pulled. - * This will begin the "decay" phase of the effect. After calling this method - * the host view should {@link android.view.View#invalidate()} and thereby - * draw the results accordingly. - */ - public void onRelease() { - mPullDistance = 0; - - if (mState != STATE_PULL && mState != STATE_PULL_DECAY) { - return; - } - - mState = STATE_RECEDE; - mEdgeAlphaStart = mEdgeAlpha; - mEdgeScaleYStart = mEdgeScaleY; - mGlowAlphaStart = mGlowAlpha; - mGlowScaleYStart = mGlowScaleY; - - mEdgeAlphaFinish = 0.f; - mEdgeScaleYFinish = 0.f; - mGlowAlphaFinish = 0.f; - mGlowScaleYFinish = 0.f; - - mStartTime = AnimationTime.get(); - mDuration = RECEDE_TIME; - } - - /** - * Call when the effect absorbs an impact at the given velocity. - * Used when a fling reaches the scroll boundary. - * - * <p>When using a {@link android.widget.Scroller} or {@link android.widget.OverScroller}, - * the method <code>getCurrVelocity</code> will provide a reasonable approximation - * to use here.</p> - * - * @param velocity Velocity at impact in pixels per second. - */ - public void onAbsorb(int velocity) { - mState = STATE_ABSORB; - velocity = Math.max(MIN_VELOCITY, Math.abs(velocity)); - - mStartTime = AnimationTime.get(); - mDuration = 0.1f + (velocity * 0.03f); - - // The edge should always be at least partially visible, regardless - // of velocity. - mEdgeAlphaStart = 0.f; - mEdgeScaleY = mEdgeScaleYStart = 0.f; - // The glow depends more on the velocity, and therefore starts out - // nearly invisible. - mGlowAlphaStart = 0.5f; - mGlowScaleYStart = 0.f; - - // Factor the velocity by 8. Testing on device shows this works best to - // reflect the strength of the user's scrolling. - mEdgeAlphaFinish = Math.max(0, Math.min(velocity * VELOCITY_EDGE_FACTOR, 1)); - // Edge should never get larger than the size of its asset. - mEdgeScaleYFinish = Math.max( - HELD_EDGE_SCALE_Y, Math.min(velocity * VELOCITY_EDGE_FACTOR, 1.f)); - - // Growth for the size of the glow should be quadratic to properly - // respond - // to a user's scrolling speed. The faster the scrolling speed, the more - // intense the effect should be for both the size and the saturation. - mGlowScaleYFinish = Math.min(0.025f + (velocity * (velocity / 100) * 0.00015f), 1.75f); - // Alpha should change for the glow as well as size. - mGlowAlphaFinish = Math.max( - mGlowAlphaStart, Math.min(velocity * VELOCITY_GLOW_FACTOR * .00001f, MAX_ALPHA)); - } - - - /** - * Draw into the provided canvas. Assumes that the canvas has been rotated - * accordingly and the size has been set. The effect will be drawn the full - * width of X=0 to X=width, beginning from Y=0 and extending to some factor < - * 1.f of height. - * - * @param canvas Canvas to draw into - * @return true if drawing should continue beyond this frame to continue the - * animation - */ - public boolean draw(GLCanvas canvas) { - update(); - - final int edgeHeight = mEdge.getIntrinsicHeight(); - final int edgeWidth = mEdge.getIntrinsicWidth(); - final int glowHeight = mGlow.getIntrinsicHeight(); - final int glowWidth = mGlow.getIntrinsicWidth(); - - mGlow.setAlpha((int) (Math.max(0, Math.min(mGlowAlpha, 1)) * 255)); - - int glowBottom = (int) Math.min( - glowHeight * mGlowScaleY * glowHeight/ glowWidth * 0.6f, - glowHeight * MAX_GLOW_HEIGHT); - if (mWidth < mMinWidth) { - // Center the glow and clip it. - int glowLeft = (mWidth - mMinWidth)/2; - mGlow.setBounds(glowLeft, 0, mWidth - glowLeft, glowBottom); - } else { - // Stretch the glow to fit. - mGlow.setBounds(0, 0, mWidth, glowBottom); - } - - mGlow.draw(canvas); - - mEdge.setAlpha((int) (Math.max(0, Math.min(mEdgeAlpha, 1)) * 255)); - - int edgeBottom = (int) (edgeHeight * mEdgeScaleY); - if (mWidth < mMinWidth) { - // Center the edge and clip it. - int edgeLeft = (mWidth - mMinWidth)/2; - mEdge.setBounds(edgeLeft, 0, mWidth - edgeLeft, edgeBottom); - } else { - // Stretch the edge to fit. - mEdge.setBounds(0, 0, mWidth, edgeBottom); - } - mEdge.draw(canvas); - - return mState != STATE_IDLE; - } - - private void update() { - final long time = AnimationTime.get(); - final float t = Math.min((time - mStartTime) / mDuration, 1.f); - - final float interp = mInterpolator.getInterpolation(t); - - mEdgeAlpha = mEdgeAlphaStart + (mEdgeAlphaFinish - mEdgeAlphaStart) * interp; - mEdgeScaleY = mEdgeScaleYStart + (mEdgeScaleYFinish - mEdgeScaleYStart) * interp; - mGlowAlpha = mGlowAlphaStart + (mGlowAlphaFinish - mGlowAlphaStart) * interp; - mGlowScaleY = mGlowScaleYStart + (mGlowScaleYFinish - mGlowScaleYStart) * interp; - - if (t >= 1.f - EPSILON) { - switch (mState) { - case STATE_ABSORB: - mState = STATE_RECEDE; - mStartTime = AnimationTime.get(); - mDuration = RECEDE_TIME; - - mEdgeAlphaStart = mEdgeAlpha; - mEdgeScaleYStart = mEdgeScaleY; - mGlowAlphaStart = mGlowAlpha; - mGlowScaleYStart = mGlowScaleY; - - // After absorb, the glow and edge should fade to nothing. - mEdgeAlphaFinish = 0.f; - mEdgeScaleYFinish = 0.f; - mGlowAlphaFinish = 0.f; - mGlowScaleYFinish = 0.f; - break; - case STATE_PULL: - mState = STATE_PULL_DECAY; - mStartTime = AnimationTime.get(); - mDuration = PULL_DECAY_TIME; - - mEdgeAlphaStart = mEdgeAlpha; - mEdgeScaleYStart = mEdgeScaleY; - mGlowAlphaStart = mGlowAlpha; - mGlowScaleYStart = mGlowScaleY; - - // After pull, the glow and edge should fade to nothing. - mEdgeAlphaFinish = 0.f; - mEdgeScaleYFinish = 0.f; - mGlowAlphaFinish = 0.f; - mGlowScaleYFinish = 0.f; - break; - case STATE_PULL_DECAY: - // When receding, we want edge to decrease more slowly - // than the glow. - float factor = mGlowScaleYFinish != 0 ? 1 - / (mGlowScaleYFinish * mGlowScaleYFinish) - : Float.MAX_VALUE; - mEdgeScaleY = mEdgeScaleYStart + - (mEdgeScaleYFinish - mEdgeScaleYStart) * - interp * factor; - mState = STATE_RECEDE; - break; - case STATE_RECEDE: - mState = STATE_IDLE; - break; - } - } - } - - private static class Drawable extends ResourceTexture { - private Rect mBounds = new Rect(); - private int mAlpha = 255; - - public Drawable(Context context, int resId) { - super(context, resId); - } - - public int getIntrinsicWidth() { - return getWidth(); - } - - public int getIntrinsicHeight() { - return getHeight(); - } - - public void setBounds(int left, int top, int right, int bottom) { - mBounds.set(left, top, right, bottom); - } - - public void setAlpha(int alpha) { - mAlpha = alpha; - } - - public void draw(GLCanvas canvas) { - canvas.save(GLCanvas.SAVE_FLAG_ALPHA); - canvas.multiplyAlpha(mAlpha / 255.0f); - Rect b = mBounds; - draw(canvas, b.left, b.top, b.width(), b.height()); - canvas.restore(); - } - } -} |