Adding support for clipping window transition for alternate recents.

Change-Id: Ic7df4e6c0396afc794ffc21694814c0a93f20f31

2 files changed, 111 insertions, 1 deletions

diff --git a/core/java/android/view/animation/ClipRectAnimation.java b/core/java/android/view/animation/ClipRectAnimation.java
new file mode 100644
index 0000000..2361501
--- /dev/null
+++ b/core/java/android/view/animation/ClipRectAnimation.java
@@ -0,0 +1,59 @@
+/*
+ * Copyright (C) 2014 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 android.view.animation;
+
+import android.graphics.Rect;
+
+/**
+ * An animation that controls the clip of an object. See the
+ * {@link android.view.animation full package} description for details and
+ * sample code.
+ *
+ * @hide
+ */
+public class ClipRectAnimation extends Animation {
+    private Rect mFromRect = new Rect();
+    private Rect mToRect = new Rect();
+
+    /**
+     * Constructor to use when building a ClipRectAnimation from code
+     *
+     * @param fromClip the clip rect to animate from
+     * @param toClip the clip rect to animate to
+     */
+    public ClipRectAnimation(Rect fromClip, Rect toClip) {
+        if (fromClip == null || toClip == null) {
+            throw new RuntimeException("Expected non-null animation clip rects");
+        }
+        mFromRect.set(fromClip);
+        mToRect.set(toClip);
+    }
+
+    @Override
+    protected void applyTransformation(float it, Transformation tr) {
+        int l = mFromRect.left + (int) ((mToRect.left - mFromRect.left) * it);
+        int t = mFromRect.top + (int) ((mToRect.top - mFromRect.top) * it);
+        int r = mFromRect.right + (int) ((mToRect.right - mFromRect.right) * it);
+        int b = mFromRect.bottom + (int) ((mToRect.bottom - mFromRect.bottom) * it);
+        tr.setClipRect(l, t, r, b);
+    }
+
+    @Override
+    public boolean willChangeTransformationMatrix() {
+        return false;
+    }
+}
diff --git a/core/java/android/view/animation/Transformation.java b/core/java/android/view/animation/Transformation.java
index 890909b..2f4fe73 100644
--- a/core/java/android/view/animation/Transformation.java
+++ b/core/java/android/view/animation/Transformation.java
@@ -17,6 +17,7 @@
 package android.view.animation;
 
 import android.graphics.Matrix;
+import android.graphics.Rect;
 
 import java.io.PrintWriter;
 
@@ -47,6 +48,9 @@ public class Transformation {
     protected float mAlpha;
     protected int mTransformationType;
 
+    private boolean mHasClipRect;
+    private Rect mClipRect = new Rect();
+
     /**
      * Creates a new transformation with alpha = 1 and the identity matrix.
      */
@@ -65,6 +69,8 @@ public class Transformation {
         } else {
             mMatrix.reset();
         }
+        mClipRect.setEmpty();
+        mHasClipRect = false;
         mAlpha = 1.0f;
         mTransformationType = TYPE_BOTH;
     }
@@ -98,9 +104,15 @@ public class Transformation {
     public void set(Transformation t) {
         mAlpha = t.getAlpha();
         mMatrix.set(t.getMatrix());
+        if (t.mHasClipRect) {
+            setClipRect(t.getClipRect());
+        } else {
+            mHasClipRect = false;
+            mClipRect.setEmpty();
+        }
         mTransformationType = t.getTransformationType();
     }
-    
+
     /**
      * Apply this Transformation to an existing Transformation, e.g. apply
      * a scale effect to something that has already been rotated.
@@ -109,6 +121,9 @@ public class Transformation {
     public void compose(Transformation t) {
         mAlpha *= t.getAlpha();
         mMatrix.preConcat(t.getMatrix());
+        if (t.mHasClipRect) {
+            setClipRect(t.getClipRect());
+        }
     }
     
     /**
@@ -119,6 +134,9 @@ public class Transformation {
     public void postCompose(Transformation t) {
         mAlpha *= t.getAlpha();
         mMatrix.postConcat(t.getMatrix());
+        if (t.mHasClipRect) {
+            setClipRect(t.getClipRect());
+        }
     }
 
     /**
@@ -138,6 +156,39 @@ public class Transformation {
     }
 
     /**
+     * Sets the current Transform's clip rect
+     * @hide
+     */
+    public void setClipRect(Rect r) {
+        setClipRect(r.left, r.top, r.right, r.bottom);
+    }
+
+    /**
+     * Sets the current Transform's clip rect
+     * @hide
+     */
+    public void setClipRect(int l, int t, int r, int b) {
+        mClipRect.set(l, t, r, b);
+        mHasClipRect = true;
+    }
+
+    /**
+     * Returns the current Transform's clip rect
+     * @hide
+     */
+    public Rect getClipRect() {
+        return mClipRect;
+    }
+
+    /**
+     * Returns whether the current Transform's clip rect is set
+     * @hide
+     */
+    public boolean hasClipRect() {
+        return mHasClipRect;
+    }
+
+    /**
      * @return The degree of transparency
      */
     public float getAlpha() {