From 675c7d2eb8198c7b68c02da731bc2c5b71d5eb5b Mon Sep 17 00:00:00 2001
From: Grace Kloba <klobag@google.com>
Date: Thu, 23 Jul 2009 09:21:21 -0700
Subject: [PATCH] Fix 1997929. The final mScrollX/Y has been pinned to the
 legal bounds. So we can't use it to calculate the intermediate scroll
 position. Use the original scroll offset and scale to find the animated
 scroll position.

---
 core/java/android/webkit/WebView.java | 31 +++++++++++----------------
 1 file changed, 13 insertions(+), 18 deletions(-)

diff --git a/core/java/android/webkit/WebView.java b/core/java/android/webkit/WebView.java
index 9ce95d6fde50e..9eaa9a3d62394 100644
--- a/core/java/android/webkit/WebView.java
+++ b/core/java/android/webkit/WebView.java
@@ -531,6 +531,8 @@ public class WebView extends AbsoluteLayout
     private float mZoomScale;
     private float mInvInitialZoomScale;
     private float mInvFinalZoomScale;
+    private int mInitialScrollX;
+    private int mInitialScrollY;
     private long mZoomStart;
     private static final int ZOOM_ANIMATION_LENGTH = 500;
 
@@ -2558,24 +2560,15 @@ public class WebView extends AbsoluteLayout
                 // set mZoomScale to be 0 as we have done animation
                 mZoomScale = 0;
             }
-            float scale = (mActualScale - zoomScale) * mInvActualScale;
-            float tx = scale * (mZoomCenterX + mScrollX);
-            float ty = scale * (mZoomCenterY + mScrollY);
-
-            // this block pins the translate to "legal" bounds. This makes the
-            // animation a bit non-obvious, but it means we won't pop when the
-            // "real" zoom takes effect
-            if (true) {
-               // canvas.translate(mScrollX, mScrollY);
-                tx -= mScrollX;
-                ty -= mScrollY;
-                tx = -pinLoc(-Math.round(tx), getViewWidth(), Math
-                        .round(mContentWidth * zoomScale));
-                ty = -pinLoc(-Math.round(ty), getViewHeight(), Math
-                        .round(mContentHeight * zoomScale));
-                tx += mScrollX;
-                ty += mScrollY;
-            }
+            float scale = zoomScale * mInvInitialZoomScale;
+            int tx = Math.round(scale * (mInitialScrollX + mZoomCenterX)
+                    - mZoomCenterX);
+            tx = -pinLoc(tx, getViewWidth(), Math.round(mContentWidth
+                    * zoomScale)) + mScrollX;
+            int ty = Math.round(scale * (mInitialScrollY + mZoomCenterY)
+                    - mZoomCenterY);
+            ty = -pinLoc(ty, getViewHeight(), Math.round(mContentHeight
+                    * zoomScale)) + mScrollY;
             canvas.translate(tx, ty);
             canvas.scale(zoomScale, zoomScale);
         } else {
@@ -4350,6 +4343,8 @@ public class WebView extends AbsoluteLayout
 
     private boolean zoomWithPreview(float scale) {
         float oldScale = mActualScale;
+        mInitialScrollX = mScrollX;
+        mInitialScrollY = mScrollY;
 
         // snap to DEFAULT_SCALE if it is close
         if (scale > (mDefaultScale - 0.05) && scale < (mDefaultScale + 0.05)) {