Merge "Extract PreviewPositionHelper to shared library" into tm-qpr-dev

packages/SystemUI/shared/src/com/android/systemui/shared/recents/utilities/PreviewPositionHelper.java

@@ -0,0 +1,209 @@
+package com.android.systemui.shared.recents.utilities;
+
+import static android.app.WindowConfiguration.WINDOWING_MODE_FULLSCREEN;
+
+import android.graphics.Matrix;
+import android.graphics.Rect;
+import android.graphics.RectF;
+import android.view.Surface;
+
+import com.android.systemui.shared.recents.model.ThumbnailData;
+
+/**
+ * Utility class to position the thumbnail in the TaskView
+ */
+public class PreviewPositionHelper {
+
+    public static final float MAX_PCT_BEFORE_ASPECT_RATIOS_CONSIDERED_DIFFERENT = 0.1f;
+
+    // Contains the portion of the thumbnail that is unclipped when fullscreen progress = 1.
+    private final RectF mClippedInsets = new RectF();
+    private final Matrix mMatrix = new Matrix();
+    private boolean mIsOrientationChanged;
+
+    public Matrix getMatrix() {
+        return mMatrix;
+    }
+
+    public void setOrientationChanged(boolean orientationChanged) {
+        mIsOrientationChanged = orientationChanged;
+    }
+
+    public boolean isOrientationChanged() {
+        return mIsOrientationChanged;
+    }
+
+    /**
+     * Updates the matrix based on the provided parameters
+     */
+    public void updateThumbnailMatrix(Rect thumbnailBounds, ThumbnailData thumbnailData,
+            int canvasWidth, int canvasHeight, int screenWidthPx, int taskbarSize, boolean isTablet,
+            int currentRotation, boolean isRtl) {
+        boolean isRotated = false;
+        boolean isOrientationDifferent;
+
+        int thumbnailRotation = thumbnailData.rotation;
+        int deltaRotate = getRotationDelta(currentRotation, thumbnailRotation);
+        RectF thumbnailClipHint = new RectF();
+        float canvasScreenRatio = canvasWidth / (float) screenWidthPx;
+        float scaledTaskbarSize = taskbarSize * canvasScreenRatio;
+        thumbnailClipHint.bottom = isTablet ? scaledTaskbarSize : 0;
+
+        float scale = thumbnailData.scale;
+        final float thumbnailScale;
+
+        // Landscape vs portrait change.
+        // Note: Disable rotation in grid layout.
+        boolean windowingModeSupportsRotation =
+                thumbnailData.windowingMode == WINDOWING_MODE_FULLSCREEN && !isTablet;
+        isOrientationDifferent = isOrientationChange(deltaRotate)
+                && windowingModeSupportsRotation;
+        if (canvasWidth == 0 || canvasHeight == 0 || scale == 0) {
+            // If we haven't measured , skip the thumbnail drawing and only draw the background
+            // color
+            thumbnailScale = 0f;
+        } else {
+            // Rotate the screenshot if not in multi-window mode
+            isRotated = deltaRotate > 0 && windowingModeSupportsRotation;
+
+            float surfaceWidth = thumbnailBounds.width() / scale;
+            float surfaceHeight = thumbnailBounds.height() / scale;
+            float availableWidth = surfaceWidth
+                    - (thumbnailClipHint.left + thumbnailClipHint.right);
+            float availableHeight = surfaceHeight
+                    - (thumbnailClipHint.top + thumbnailClipHint.bottom);
+
+            float canvasAspect = canvasWidth / (float) canvasHeight;
+            float availableAspect = isRotated
+                    ? availableHeight / availableWidth
+                    : availableWidth / availableHeight;
+            boolean isAspectLargelyDifferent =
+                    Utilities.isRelativePercentDifferenceGreaterThan(canvasAspect,
+                            availableAspect, MAX_PCT_BEFORE_ASPECT_RATIOS_CONSIDERED_DIFFERENT);
+            if (isRotated && isAspectLargelyDifferent) {
+                // Do not rotate thumbnail if it would not improve fit
+                isRotated = false;
+                isOrientationDifferent = false;
+            }
+
+            if (isAspectLargelyDifferent) {
+                // Crop letterbox insets if insets isn't already clipped
+                thumbnailClipHint.left = thumbnailData.letterboxInsets.left;
+                thumbnailClipHint.right = thumbnailData.letterboxInsets.right;
+                thumbnailClipHint.top = thumbnailData.letterboxInsets.top;
+                thumbnailClipHint.bottom = thumbnailData.letterboxInsets.bottom;
+                availableWidth = surfaceWidth
+                        - (thumbnailClipHint.left + thumbnailClipHint.right);
+                availableHeight = surfaceHeight
+                        - (thumbnailClipHint.top + thumbnailClipHint.bottom);
+            }
+
+            final float targetW, targetH;
+            if (isOrientationDifferent) {
+                targetW = canvasHeight;
+                targetH = canvasWidth;
+            } else {
+                targetW = canvasWidth;
+                targetH = canvasHeight;
+            }
+            float targetAspect = targetW / targetH;
+
+            // Update the clipHint such that
+            //   > the final clipped position has same aspect ratio as requested by canvas
+            //   > first fit the width and crop the extra height
+            //   > if that will leave empty space, fit the height and crop the width instead
+            float croppedWidth = availableWidth;
+            float croppedHeight = croppedWidth / targetAspect;
+            if (croppedHeight > availableHeight) {
+                croppedHeight = availableHeight;
+                if (croppedHeight < targetH) {
+                    croppedHeight = Math.min(targetH, surfaceHeight);
+                }
+                croppedWidth = croppedHeight * targetAspect;
+
+                // One last check in case the task aspect radio messed up something
+                if (croppedWidth > surfaceWidth) {
+                    croppedWidth = surfaceWidth;
+                    croppedHeight = croppedWidth / targetAspect;
+                }
+            }
+
+            // Update the clip hints. Align to 0,0, crop the remaining.
+            if (isRtl) {
+                thumbnailClipHint.left += availableWidth - croppedWidth;
+                if (thumbnailClipHint.right < 0) {
+                    thumbnailClipHint.left += thumbnailClipHint.right;
+                    thumbnailClipHint.right = 0;
+                }
+            } else {
+                thumbnailClipHint.right += availableWidth - croppedWidth;
+                if (thumbnailClipHint.left < 0) {
+                    thumbnailClipHint.right += thumbnailClipHint.left;
+                    thumbnailClipHint.left = 0;
+                }
+            }
+            thumbnailClipHint.bottom += availableHeight - croppedHeight;
+            if (thumbnailClipHint.top < 0) {
+                thumbnailClipHint.bottom += thumbnailClipHint.top;
+                thumbnailClipHint.top = 0;
+            } else if (thumbnailClipHint.bottom < 0) {
+                thumbnailClipHint.top += thumbnailClipHint.bottom;
+                thumbnailClipHint.bottom = 0;
+            }
+
+            thumbnailScale = targetW / (croppedWidth * scale);
+        }
+
+        if (!isRotated) {
+            mMatrix.setTranslate(
+                    -thumbnailClipHint.left * scale,
+                    -thumbnailClipHint.top * scale);
+        } else {
+            setThumbnailRotation(deltaRotate, thumbnailBounds);
+        }
+
+        mClippedInsets.set(0, 0, 0, scaledTaskbarSize);
+
+        mMatrix.postScale(thumbnailScale, thumbnailScale);
+        mIsOrientationChanged = isOrientationDifferent;
+    }
+
+    private int getRotationDelta(int oldRotation, int newRotation) {
+        int delta = newRotation - oldRotation;
+        if (delta < 0) delta += 4;
+        return delta;
+    }
+
+    /**
+     * @param deltaRotation the number of 90 degree turns from the current orientation
+     * @return {@code true} if the change in rotation results in a shift from landscape to
+     * portrait or vice versa, {@code false} otherwise
+     */
+    private boolean isOrientationChange(int deltaRotation) {
+        return deltaRotation == Surface.ROTATION_90 || deltaRotation == Surface.ROTATION_270;
+    }
+
+    private void setThumbnailRotation(int deltaRotate, Rect thumbnailPosition) {
+        float translateX = 0;
+        float translateY = 0;
+
+        mMatrix.setRotate(90 * deltaRotate);
+        switch (deltaRotate) { /* Counter-clockwise */
+            case Surface.ROTATION_90:
+                translateX = thumbnailPosition.height();
+                break;
+            case Surface.ROTATION_270:
+                translateY = thumbnailPosition.width();
+                break;
+            case Surface.ROTATION_180:
+                translateX = thumbnailPosition.width();
+                translateY = thumbnailPosition.height();
+                break;
+        }
+        mMatrix.postTranslate(translateX, translateY);
+    }
+
+    public RectF getClippedInsets() {
+        return mClippedInsets;
+    }
+}

packages/SystemUI/shared/src/com/android/systemui/shared/recents/utilities/Utilities.java

@@ -62,6 +62,16 @@ public class Utilities {
         return false; // Default
     }
 
+    /**
+     * Compares the ratio of two quantities and returns whether that ratio is greater than the
+     * provided bound. Order of quantities does not matter. Bound should be a decimal representation
+     * of a percentage.
+     */
+    public static boolean isRelativePercentDifferenceGreaterThan(float first, float second,
+            float bound) {
+        return (Math.abs(first - second) / Math.abs((first + second) / 2.0f)) > bound;
+    }
+
     /** Calculates the constrast between two colors, using the algorithm provided by the WCAG v2. */
     public static float computeContrastBetweenColors(int bg, int fg) {
         float bgR = Color.red(bg) / 255f;