| /* |
| * Copyright (C) 2016 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.internal.policy; |
| |
| import android.content.Context; |
| import android.content.res.Configuration; |
| import android.content.res.Resources; |
| import android.graphics.Point; |
| import android.graphics.PointF; |
| import android.graphics.Rect; |
| import android.util.Size; |
| import android.view.Gravity; |
| |
| import java.io.PrintWriter; |
| import java.util.ArrayList; |
| |
| /** |
| * Calculates the snap targets and the snap position for the PIP given a position and a velocity. |
| * All bounds are relative to the display top/left. |
| */ |
| public class PipSnapAlgorithm { |
| |
| // The below SNAP_MODE_* constants correspond to the config resource value |
| // config_pictureInPictureSnapMode and should not be changed independently. |
| // Allows snapping to the four corners |
| private static final int SNAP_MODE_CORNERS_ONLY = 0; |
| // Allows snapping to the four corners and the mid-points on the long edge in each orientation |
| private static final int SNAP_MODE_CORNERS_AND_SIDES = 1; |
| // Allows snapping to anywhere along the edge of the screen |
| private static final int SNAP_MODE_EDGE = 2; |
| // Allows snapping anywhere along the edge of the screen and magnets towards corners |
| private static final int SNAP_MODE_EDGE_MAGNET_CORNERS = 3; |
| // Allows snapping on the long edge in each orientation and magnets towards corners |
| private static final int SNAP_MODE_LONG_EDGE_MAGNET_CORNERS = 4; |
| |
| // Threshold to magnet to a corner |
| private static final float CORNER_MAGNET_THRESHOLD = 0.3f; |
| |
| private final Context mContext; |
| |
| private final ArrayList<Integer> mSnapGravities = new ArrayList<>(); |
| private final int mDefaultSnapMode = SNAP_MODE_EDGE_MAGNET_CORNERS; |
| private int mSnapMode = mDefaultSnapMode; |
| |
| private final float mDefaultSizePercent; |
| private final float mMinAspectRatioForMinSize; |
| private final float mMaxAspectRatioForMinSize; |
| private final int mFlingDeceleration; |
| |
| private int mOrientation = Configuration.ORIENTATION_UNDEFINED; |
| |
| private final int mMinimizedVisibleSize; |
| private boolean mIsMinimized; |
| |
| public PipSnapAlgorithm(Context context) { |
| Resources res = context.getResources(); |
| mContext = context; |
| mMinimizedVisibleSize = res.getDimensionPixelSize( |
| com.android.internal.R.dimen.pip_minimized_visible_size); |
| mDefaultSizePercent = res.getFloat( |
| com.android.internal.R.dimen.config_pictureInPictureDefaultSizePercent); |
| mMaxAspectRatioForMinSize = res.getFloat( |
| com.android.internal.R.dimen.config_pictureInPictureAspectRatioLimitForMinSize); |
| mMinAspectRatioForMinSize = 1f / mMaxAspectRatioForMinSize; |
| mFlingDeceleration = mContext.getResources().getDimensionPixelSize( |
| com.android.internal.R.dimen.pip_fling_deceleration); |
| onConfigurationChanged(); |
| } |
| |
| /** |
| * Updates the snap algorithm when the configuration changes. |
| */ |
| public void onConfigurationChanged() { |
| Resources res = mContext.getResources(); |
| mOrientation = res.getConfiguration().orientation; |
| mSnapMode = res.getInteger(com.android.internal.R.integer.config_pictureInPictureSnapMode); |
| calculateSnapTargets(); |
| } |
| |
| /** |
| * Sets the PIP's minimized state. |
| */ |
| public void setMinimized(boolean isMinimized) { |
| mIsMinimized = isMinimized; |
| } |
| |
| /** |
| * @return the closest absolute snap stack bounds for the given {@param stackBounds} moving at |
| * the given {@param velocityX} and {@param velocityY}. The {@param movementBounds} should be |
| * those for the given {@param stackBounds}. |
| */ |
| public Rect findClosestSnapBounds(Rect movementBounds, Rect stackBounds, float velocityX, |
| float velocityY, Point dragStartPosition) { |
| final Rect intersectStackBounds = new Rect(stackBounds); |
| final Point intersect = getEdgeIntersect(stackBounds, movementBounds, velocityX, velocityY, |
| dragStartPosition); |
| intersectStackBounds.offsetTo(intersect.x, intersect.y); |
| return findClosestSnapBounds(movementBounds, intersectStackBounds); |
| } |
| |
| /** |
| * @return The point along the {@param movementBounds} that the PIP would intersect with based |
| * on the provided {@param velX}, {@param velY} along with the position of the PIP when |
| * the gesture started, {@param dragStartPosition}. |
| */ |
| public Point getEdgeIntersect(Rect stackBounds, Rect movementBounds, float velX, float velY, |
| Point dragStartPosition) { |
| final boolean isLandscape = mOrientation == Configuration.ORIENTATION_LANDSCAPE; |
| final int x = stackBounds.left; |
| final int y = stackBounds.top; |
| |
| // Find the line of movement the PIP is on. Line defined by: y = slope * x + yIntercept |
| final float slope = velY / velX; // slope = rise / run |
| final float yIntercept = y - slope * x; // rearrange line equation for yIntercept |
| // The PIP can have two intercept points: |
| // 1) Where the line intersects with one of the edges of the screen (vertical line) |
| Point vertPoint = new Point(); |
| // 2) Where the line intersects with the top or bottom of the screen (horizontal line) |
| Point horizPoint = new Point(); |
| |
| // Find the vertical line intersection, x will be one of the edges |
| vertPoint.x = velX > 0 ? movementBounds.right : movementBounds.left; |
| // Sub in x in our line equation to determine y position |
| vertPoint.y = findY(slope, yIntercept, vertPoint.x); |
| |
| // Find the horizontal line intersection, y will be the top or bottom of the screen |
| horizPoint.y = velY > 0 ? movementBounds.bottom : movementBounds.top; |
| // Sub in y in our line equation to determine x position |
| horizPoint.x = findX(slope, yIntercept, horizPoint.y); |
| |
| // Now pick one of these points -- first determine if we're flinging along the current edge. |
| // Only fling along current edge if it's a direction with space for the PIP to move to |
| int maxDistance; |
| if (isLandscape) { |
| maxDistance = velX > 0 |
| ? movementBounds.right - stackBounds.left |
| : stackBounds.left - movementBounds.left; |
| } else { |
| maxDistance = velY > 0 |
| ? movementBounds.bottom - stackBounds.top |
| : stackBounds.top - movementBounds.top; |
| } |
| if (maxDistance > 0) { |
| // Only fling along the current edge if the start and end point are on the same side |
| final int startPoint = isLandscape ? dragStartPosition.y : dragStartPosition.x; |
| final int endPoint = isLandscape ? horizPoint.y : horizPoint.x; |
| final int center = movementBounds.centerX(); |
| if ((startPoint < center && endPoint < center) |
| || (startPoint > center && endPoint > center)) { |
| // We are flinging along the current edge, figure out how far it should travel |
| // based on velocity and assumed deceleration. |
| int distance = (int) (0 - Math.pow(isLandscape ? velX : velY, 2)) |
| / (2 * mFlingDeceleration); |
| distance = Math.min(distance, maxDistance); |
| // Adjust the point for the distance |
| if (isLandscape) { |
| horizPoint.x = stackBounds.left + (velX > 0 ? distance : -distance); |
| } else { |
| horizPoint.y = stackBounds.top + (velY > 0 ? distance : -distance); |
| } |
| return horizPoint; |
| } |
| } |
| // If we're not flinging along the current edge, find the closest point instead. |
| final double distanceVert = Math.hypot(vertPoint.x - x, vertPoint.y - y); |
| final double distanceHoriz = Math.hypot(horizPoint.x - x, horizPoint.y - y); |
| return Math.abs(distanceVert) > Math.abs(distanceHoriz) ? horizPoint : vertPoint; |
| } |
| |
| private int findY(float slope, float yIntercept, float x) { |
| return (int) ((slope * x) + yIntercept); |
| } |
| |
| private int findX(float slope, float yIntercept, float y) { |
| return (int) ((y - yIntercept) / slope); |
| } |
| |
| /** |
| * @return the closest absolute snap stack bounds for the given {@param stackBounds}. The |
| * {@param movementBounds} should be those for the given {@param stackBounds}. |
| */ |
| public Rect findClosestSnapBounds(Rect movementBounds, Rect stackBounds) { |
| final Rect pipBounds = new Rect(movementBounds.left, movementBounds.top, |
| movementBounds.right + stackBounds.width(), |
| movementBounds.bottom + stackBounds.height()); |
| final Rect newBounds = new Rect(stackBounds); |
| if (mSnapMode == SNAP_MODE_LONG_EDGE_MAGNET_CORNERS |
| || mSnapMode == SNAP_MODE_EDGE_MAGNET_CORNERS) { |
| final Rect tmpBounds = new Rect(); |
| final Point[] snapTargets = new Point[mSnapGravities.size()]; |
| for (int i = 0; i < mSnapGravities.size(); i++) { |
| Gravity.apply(mSnapGravities.get(i), stackBounds.width(), stackBounds.height(), |
| pipBounds, 0, 0, tmpBounds); |
| snapTargets[i] = new Point(tmpBounds.left, tmpBounds.top); |
| } |
| Point snapTarget = findClosestPoint(stackBounds.left, stackBounds.top, snapTargets); |
| float distance = distanceToPoint(snapTarget, stackBounds.left, stackBounds.top); |
| final float thresh = Math.max(stackBounds.width(), stackBounds.height()) |
| * CORNER_MAGNET_THRESHOLD; |
| if (distance < thresh) { |
| newBounds.offsetTo(snapTarget.x, snapTarget.y); |
| } else { |
| snapRectToClosestEdge(stackBounds, movementBounds, newBounds); |
| } |
| } else if (mSnapMode == SNAP_MODE_EDGE) { |
| // Find the closest edge to the given stack bounds and snap to it |
| snapRectToClosestEdge(stackBounds, movementBounds, newBounds); |
| } else { |
| // Find the closest snap point |
| final Rect tmpBounds = new Rect(); |
| final Point[] snapTargets = new Point[mSnapGravities.size()]; |
| for (int i = 0; i < mSnapGravities.size(); i++) { |
| Gravity.apply(mSnapGravities.get(i), stackBounds.width(), stackBounds.height(), |
| pipBounds, 0, 0, tmpBounds); |
| snapTargets[i] = new Point(tmpBounds.left, tmpBounds.top); |
| } |
| Point snapTarget = findClosestPoint(stackBounds.left, stackBounds.top, snapTargets); |
| newBounds.offsetTo(snapTarget.x, snapTarget.y); |
| } |
| return newBounds; |
| } |
| |
| /** |
| * Applies the offset to the {@param stackBounds} to adjust it to a minimized state. |
| */ |
| public void applyMinimizedOffset(Rect stackBounds, Rect movementBounds, Point displaySize, |
| Rect stableInsets) { |
| if (stackBounds.left <= movementBounds.centerX()) { |
| stackBounds.offsetTo(stableInsets.left + mMinimizedVisibleSize - stackBounds.width(), |
| stackBounds.top); |
| } else { |
| stackBounds.offsetTo(displaySize.x - stableInsets.right - mMinimizedVisibleSize, |
| stackBounds.top); |
| } |
| } |
| |
| /** |
| * @return returns a fraction that describes where along the {@param movementBounds} the |
| * {@param stackBounds} are. If the {@param stackBounds} are not currently on the |
| * {@param movementBounds} exactly, then they will be snapped to the movement bounds. |
| * |
| * The fraction is defined in a clockwise fashion against the {@param movementBounds}: |
| * |
| * 0 1 |
| * 4 +---+ 1 |
| * | | |
| * 3 +---+ 2 |
| * 3 2 |
| */ |
| public float getSnapFraction(Rect stackBounds, Rect movementBounds) { |
| final Rect tmpBounds = new Rect(); |
| snapRectToClosestEdge(stackBounds, movementBounds, tmpBounds); |
| final float widthFraction = (float) (tmpBounds.left - movementBounds.left) / |
| movementBounds.width(); |
| final float heightFraction = (float) (tmpBounds.top - movementBounds.top) / |
| movementBounds.height(); |
| if (tmpBounds.top == movementBounds.top) { |
| return widthFraction; |
| } else if (tmpBounds.left == movementBounds.right) { |
| return 1f + heightFraction; |
| } else if (tmpBounds.top == movementBounds.bottom) { |
| return 2f + (1f - widthFraction); |
| } else { |
| return 3f + (1f - heightFraction); |
| } |
| } |
| |
| /** |
| * Moves the {@param stackBounds} along the {@param movementBounds} to the given snap fraction. |
| * See {@link #getSnapFraction(Rect, Rect)}. |
| * |
| * The fraction is define in a clockwise fashion against the {@param movementBounds}: |
| * |
| * 0 1 |
| * 4 +---+ 1 |
| * | | |
| * 3 +---+ 2 |
| * 3 2 |
| */ |
| public void applySnapFraction(Rect stackBounds, Rect movementBounds, float snapFraction) { |
| if (snapFraction < 1f) { |
| int offset = movementBounds.left + (int) (snapFraction * movementBounds.width()); |
| stackBounds.offsetTo(offset, movementBounds.top); |
| } else if (snapFraction < 2f) { |
| snapFraction -= 1f; |
| int offset = movementBounds.top + (int) (snapFraction * movementBounds.height()); |
| stackBounds.offsetTo(movementBounds.right, offset); |
| } else if (snapFraction < 3f) { |
| snapFraction -= 2f; |
| int offset = movementBounds.left + (int) ((1f - snapFraction) * movementBounds.width()); |
| stackBounds.offsetTo(offset, movementBounds.bottom); |
| } else { |
| snapFraction -= 3f; |
| int offset = movementBounds.top + (int) ((1f - snapFraction) * movementBounds.height()); |
| stackBounds.offsetTo(movementBounds.left, offset); |
| } |
| } |
| |
| /** |
| * Adjusts {@param movementBoundsOut} so that it is the movement bounds for the given |
| * {@param stackBounds}. |
| */ |
| public void getMovementBounds(Rect stackBounds, Rect insetBounds, Rect movementBoundsOut, |
| int bottomOffset) { |
| // Adjust the right/bottom to ensure the stack bounds never goes offscreen |
| movementBoundsOut.set(insetBounds); |
| movementBoundsOut.right = Math.max(insetBounds.left, insetBounds.right - |
| stackBounds.width()); |
| movementBoundsOut.bottom = Math.max(insetBounds.top, insetBounds.bottom - |
| stackBounds.height()); |
| movementBoundsOut.bottom -= bottomOffset; |
| } |
| |
| /** |
| * @return the size of the PiP at the given {@param aspectRatio}, ensuring that the minimum edge |
| * is at least {@param minEdgeSize}. |
| */ |
| public Size getSizeForAspectRatio(float aspectRatio, float minEdgeSize, int displayWidth, |
| int displayHeight) { |
| final int smallestDisplaySize = Math.min(displayWidth, displayHeight); |
| final int minSize = (int) Math.max(minEdgeSize, smallestDisplaySize * mDefaultSizePercent); |
| |
| final int width; |
| final int height; |
| if (aspectRatio <= mMinAspectRatioForMinSize || aspectRatio > mMaxAspectRatioForMinSize) { |
| // Beyond these points, we can just use the min size as the shorter edge |
| if (aspectRatio <= 1) { |
| // Portrait, width is the minimum size |
| width = minSize; |
| height = Math.round(width / aspectRatio); |
| } else { |
| // Landscape, height is the minimum size |
| height = minSize; |
| width = Math.round(height * aspectRatio); |
| } |
| } else { |
| // Within these points, we ensure that the bounds fit within the radius of the limits |
| // at the points |
| final float widthAtMaxAspectRatioForMinSize = mMaxAspectRatioForMinSize * minSize; |
| final float radius = PointF.length(widthAtMaxAspectRatioForMinSize, minSize); |
| height = (int) Math.round(Math.sqrt((radius * radius) / |
| (aspectRatio * aspectRatio + 1))); |
| width = Math.round(height * aspectRatio); |
| } |
| return new Size(width, height); |
| } |
| |
| /** |
| * @return the adjusted size so that it conforms to the given aspectRatio, ensuring that the |
| * minimum edge is at least minEdgeSize. |
| */ |
| public Size getSizeForAspectRatio(Size size, float aspectRatio, float minEdgeSize) { |
| final int smallestSize = Math.min(size.getWidth(), size.getHeight()); |
| final int minSize = (int) Math.max(minEdgeSize, smallestSize); |
| |
| final int width; |
| final int height; |
| if (aspectRatio <= 1) { |
| // Portrait, width is the minimum size. |
| width = minSize; |
| height = Math.round(width / aspectRatio); |
| } else { |
| // Landscape, height is the minimum size |
| height = minSize; |
| width = Math.round(height * aspectRatio); |
| } |
| return new Size(width, height); |
| } |
| |
| /** |
| * @return the closest point in {@param points} to the given {@param x} and {@param y}. |
| */ |
| private Point findClosestPoint(int x, int y, Point[] points) { |
| Point closestPoint = null; |
| float minDistance = Float.MAX_VALUE; |
| for (Point p : points) { |
| float distance = distanceToPoint(p, x, y); |
| if (distance < minDistance) { |
| closestPoint = p; |
| minDistance = distance; |
| } |
| } |
| return closestPoint; |
| } |
| |
| /** |
| * Snaps the {@param stackBounds} to the closest edge of the {@param movementBounds} and writes |
| * the new bounds out to {@param boundsOut}. |
| */ |
| private void snapRectToClosestEdge(Rect stackBounds, Rect movementBounds, Rect boundsOut) { |
| // If the stackBounds are minimized, then it should only be snapped back horizontally |
| final int boundedLeft = Math.max(movementBounds.left, Math.min(movementBounds.right, |
| stackBounds.left)); |
| final int boundedTop = Math.max(movementBounds.top, Math.min(movementBounds.bottom, |
| stackBounds.top)); |
| boundsOut.set(stackBounds); |
| if (mIsMinimized) { |
| boundsOut.offsetTo(boundedLeft, boundedTop); |
| return; |
| } |
| |
| // Otherwise, just find the closest edge |
| final int fromLeft = Math.abs(stackBounds.left - movementBounds.left); |
| final int fromTop = Math.abs(stackBounds.top - movementBounds.top); |
| final int fromRight = Math.abs(movementBounds.right - stackBounds.left); |
| final int fromBottom = Math.abs(movementBounds.bottom - stackBounds.top); |
| int shortest; |
| if (mSnapMode == SNAP_MODE_LONG_EDGE_MAGNET_CORNERS) { |
| // Only check longest edges |
| shortest = (mOrientation == Configuration.ORIENTATION_LANDSCAPE) |
| ? Math.min(fromTop, fromBottom) |
| : Math.min(fromLeft, fromRight); |
| } else { |
| shortest = Math.min(Math.min(fromLeft, fromRight), Math.min(fromTop, fromBottom)); |
| } |
| if (shortest == fromLeft) { |
| boundsOut.offsetTo(movementBounds.left, boundedTop); |
| } else if (shortest == fromTop) { |
| boundsOut.offsetTo(boundedLeft, movementBounds.top); |
| } else if (shortest == fromRight) { |
| boundsOut.offsetTo(movementBounds.right, boundedTop); |
| } else { |
| boundsOut.offsetTo(boundedLeft, movementBounds.bottom); |
| } |
| } |
| |
| /** |
| * @return the distance between point {@param p} and the given {@param x} and {@param y}. |
| */ |
| private float distanceToPoint(Point p, int x, int y) { |
| return PointF.length(p.x - x, p.y - y); |
| } |
| |
| /** |
| * Calculate the snap targets for the discrete snap modes. |
| */ |
| private void calculateSnapTargets() { |
| mSnapGravities.clear(); |
| switch (mSnapMode) { |
| case SNAP_MODE_CORNERS_AND_SIDES: |
| if (mOrientation == Configuration.ORIENTATION_LANDSCAPE) { |
| mSnapGravities.add(Gravity.TOP | Gravity.CENTER_HORIZONTAL); |
| mSnapGravities.add(Gravity.BOTTOM | Gravity.CENTER_HORIZONTAL); |
| } else { |
| mSnapGravities.add(Gravity.CENTER_VERTICAL | Gravity.LEFT); |
| mSnapGravities.add(Gravity.CENTER_VERTICAL | Gravity.RIGHT); |
| } |
| // Fall through |
| case SNAP_MODE_CORNERS_ONLY: |
| case SNAP_MODE_EDGE_MAGNET_CORNERS: |
| case SNAP_MODE_LONG_EDGE_MAGNET_CORNERS: |
| mSnapGravities.add(Gravity.TOP | Gravity.LEFT); |
| mSnapGravities.add(Gravity.TOP | Gravity.RIGHT); |
| mSnapGravities.add(Gravity.BOTTOM | Gravity.LEFT); |
| mSnapGravities.add(Gravity.BOTTOM | Gravity.RIGHT); |
| break; |
| default: |
| // Skip otherwise |
| break; |
| } |
| } |
| |
| public void dump(PrintWriter pw, String prefix) { |
| final String innerPrefix = prefix + " "; |
| pw.println(prefix + PipSnapAlgorithm.class.getSimpleName()); |
| pw.println(innerPrefix + "mSnapMode=" + mSnapMode); |
| pw.println(innerPrefix + "mOrientation=" + mOrientation); |
| pw.println(innerPrefix + "mMinimizedVisibleSize=" + mMinimizedVisibleSize); |
| pw.println(innerPrefix + "mIsMinimized=" + mIsMinimized); |
| } |
| } |