Add 3D rotation to View
Change-Id: I4aa2542eb821e82d44e13d69b0938de13ffd4f0d
diff --git a/core/java/android/view/View.java b/core/java/android/view/View.java
index d48ab98..603ad89 100644
--- a/core/java/android/view/View.java
+++ b/core/java/android/view/View.java
@@ -16,6 +16,7 @@
package android.view;
+import android.graphics.Camera;
import com.android.internal.R;
import com.android.internal.view.menu.MenuBuilder;
@@ -1537,6 +1538,14 @@
private static final int AWAKEN_SCROLL_BARS_ON_ATTACH = 0x08000000;
/**
+ * Indicates that pivotX or pivotY were explicitly set and we should not assume the center
+ * for transform operations
+ *
+ * @hide
+ */
+ private static final int PIVOT_EXPLICITLY_SET = 0x10000000;
+
+ /**
* The parent this view is attached to.
* {@hide}
*
@@ -1627,6 +1636,42 @@
private boolean mMatrixIsIdentity = true;
/**
+ * The Camera object is used to compute a 3D matrix when rotationX or rotationY are set.
+ */
+ private Camera mCamera = null;
+
+ /**
+ * This matrix is used when computing the matrix for 3D rotations.
+ */
+ private Matrix matrix3D = null;
+
+ /**
+ * These prev values are used to recalculate a centered pivot point when necessary. The
+ * pivot point is only used in matrix operations (when rotation, scale, or translation are
+ * set), so thes values are only used then as well.
+ */
+ private int mPrevWidth = -1;
+ private int mPrevHeight = -1;
+
+ /**
+ * Convenience value to check for float values that are close enough to zero to be considered
+ * zero.
+ */
+ private static float NONZERO_EPSILON = .001f;
+
+ /**
+ * The degrees rotation around the vertical axis through the pivot point.
+ */
+ @ViewDebug.ExportedProperty
+ private float mRotationY = 0f;
+
+ /**
+ * The degrees rotation around the horizontal axis through the pivot point.
+ */
+ @ViewDebug.ExportedProperty
+ private float mRotationX = 0f;
+
+ /**
* The degrees rotation around the pivot point.
*/
@ViewDebug.ExportedProperty
@@ -4888,6 +4933,16 @@
}
/**
+ * Utility function to determine if the value is far enough away from zero to be
+ * considered non-zero.
+ * @param value A floating point value to check for zero-ness
+ * @return whether the passed-in value is far enough away from zero to be considered non-zero
+ */
+ private static boolean nonzero(float value) {
+ return (value < -NONZERO_EPSILON || value > NONZERO_EPSILON);
+ }
+
+ /**
* Recomputes the transform matrix if necessary.
*
* @return True if the transform matrix is the identity matrix, false otherwise.
@@ -4896,10 +4951,34 @@
if (mMatrixDirty) {
// transform-related properties have changed since the last time someone
// asked for the matrix; recalculate it with the current values
+
+ // Figure out if we need to update the pivot point
+ if ((mPrivateFlags & PIVOT_EXPLICITLY_SET) == 0) {
+ if ((mRight - mLeft) != mPrevWidth && (mBottom - mTop) != mPrevHeight) {
+ mPrevWidth = mRight - mLeft;
+ mPrevHeight = mBottom - mTop;
+ mPivotX = (float) mPrevWidth / 2f;
+ mPivotY = (float) mPrevHeight / 2f;
+ }
+ }
mMatrix.reset();
mMatrix.setTranslate(mTranslationX, mTranslationY);
mMatrix.preRotate(mRotation, mPivotX, mPivotY);
mMatrix.preScale(mScaleX, mScaleY, mPivotX, mPivotY);
+ if (nonzero(mRotationX) || nonzero(mRotationY)) {
+ if (mCamera == null) {
+ mCamera = new Camera();
+ matrix3D = new Matrix();
+ }
+ mCamera.save();
+ mCamera.rotateX(mRotationX);
+ mCamera.rotateY(mRotationY);
+ mCamera.getMatrix(matrix3D);
+ matrix3D.preTranslate(-mPivotX, -mPivotY);
+ matrix3D.postTranslate(mPivotX, mPivotY);
+ mMatrix.postConcat(matrix3D);
+ mCamera.restore();
+ }
mMatrixDirty = false;
mMatrixIsIdentity = mMatrix.isIdentity();
mInverseMatrixDirty = true;
@@ -4955,6 +5034,64 @@
}
/**
+ * The degrees that the view is rotated around the vertical axis through the pivot point.
+ *
+ * @see #getPivotX()
+ * @see #getPivotY()
+ * @return The degrees of Y rotation.
+ */
+ public float getRotationY() {
+ return mRotationY;
+ }
+
+ /**
+ * Sets the degrees that the view is rotated around the vertical axis through pivot point.
+ *
+ * @param rotationY The degrees of Y rotation.
+ * @see #getPivotX()
+ * @see #getPivotY()
+ */
+ public void setRotationY(float rotationY) {
+ if (mRotationY != rotationY) {
+ // Double-invalidation is necessary to capture view's old and new areas
+ invalidate();
+ mRotationY = rotationY;
+ mMatrixDirty = true;
+ mPrivateFlags |= DRAWN; // force another invalidation with the new orientation
+ invalidate();
+ }
+ }
+
+ /**
+ * The degrees that the view is rotated around the horizontal axis through the pivot point.
+ *
+ * @see #getPivotX()
+ * @see #getPivotY()
+ * @return The degrees of X rotation.
+ */
+ public float getRotationX() {
+ return mRotationX;
+ }
+
+ /**
+ * Sets the degrees that the view is rotated around the horizontal axis through pivot point.
+ *
+ * @param rotationX The degrees of X rotation.
+ * @see #getPivotX()
+ * @see #getPivotY()
+ */
+ public void setRotationX(float rotationX) {
+ if (mRotationX != rotationX) {
+ // Double-invalidation is necessary to capture view's old and new areas
+ invalidate();
+ mRotationX = rotationX;
+ mMatrixDirty = true;
+ mPrivateFlags |= DRAWN; // force another invalidation with the new orientation
+ invalidate();
+ }
+ }
+
+ /**
* The amount that the view is scaled in x around the pivot point, as a proportion of
* the view's unscaled width. A value of 1, the default, means that no scaling is applied.
*
@@ -5035,6 +5172,9 @@
/**
* Sets the x location of the point around which the view is
* {@link #setRotation(float) rotated} and {@link #setScaleX(float) scaled}.
+ * By default, the pivot point is centered on the object.
+ * Setting this property disables this behavior and causes the view to use only the
+ * explicitly set pivotX and pivotY values.
*
* @param pivotX The x location of the pivot point.
* @see #getRotation()
@@ -5043,6 +5183,7 @@
* @see #getPivotY()
*/
public void setPivotX(float pivotX) {
+ mPrivateFlags |= PIVOT_EXPLICITLY_SET;
if (mPivotX != pivotX) {
// Double-invalidation is necessary to capture view's old and new areas
invalidate();
@@ -5069,7 +5210,9 @@
/**
* Sets the y location of the point around which the view is {@link #setRotation(float) rotated}
- * and {@link #setScaleY(float) scaled}.
+ * and {@link #setScaleY(float) scaled}. By default, the pivot point is centered on the object.
+ * Setting this property disables this behavior and causes the view to use only the
+ * explicitly set pivotX and pivotY values.
*
* @param pivotY The y location of the pivot point.
* @see #getRotation()
@@ -5078,6 +5221,7 @@
* @see #getPivotY()
*/
public void setPivotY(float pivotY) {
+ mPrivateFlags |= PIVOT_EXPLICITLY_SET;
if (mPivotY != pivotY) {
// Double-invalidation is necessary to capture view's old and new areas
invalidate();
@@ -5312,15 +5456,6 @@
* is still within the view.
*/
private boolean pointInView(float localX, float localY, float slop) {
- if (!hasIdentityMatrix() && mAttachInfo != null) {
- // non-identity matrix: transform the point into the view's coordinates
- final float[] localXY = mAttachInfo.mTmpTransformLocation;
- localXY[0] = localX;
- localXY[1] = localY;
- getInverseMatrix().mapPoints(localXY);
- localX = localXY[0];
- localY = localXY[1];
- }
return localX > -slop && localY > -slop && localX < ((mRight - mLeft) + slop) &&
localY < ((mBottom - mTop) + slop);
}