Bug 151065 – [Mac] Gesture Events should not have negative scale

• Component: WebKit Misc.
• Status: RESOLVED FIXED

[Joseph Pecoraro]

Created attachment 265120 [details]
[TEST] Gesture Test

* SUMMARY
[Mac] Gesture Events should not have negative scale.

* STEPS TO REPRODUCE
1. Load test page
2. Pinch on the box
  => scale goes negative the box starts re-growing (due to CSS transform scale()). Did not expect the scale to ever go negative.

* NOTES
- Loading the same test case on iOS, the scale does not go negative. It approaches zero but rarely goes below 0.15. It never goes negative.
- Since scale is local to 1 (>1 = fingers moved apart, <1 = fingers moved closer together) it is natural to use a a multiplier of the start value. When values get very close to zero, or go negative, the usefulness diminish and it means a rapid change from the original value.

[Radar WebKit Bug Importer]

<rdar://problem/23474123>

[Tim Horton]

I'm not sure we have enough information (at least, the way it's currently implemented, on top of AppKit's magnification) to do anything better than maxing with 0. But, we can certainly do that.

[Tim Horton]

I don't think that's the right thing to do, though, because that would mean you could be moving your fingers and the scale wouldn't be changing.

[Tim Horton]

We'll fix these elsewhere.

[Tim Horton]

Reopened to post the WebKit bits for review.

[Tim Horton]

Created attachment 267393 [details]
patch

[WebKit Commit Bot]

Attachment 267393 [details] did not pass style-queue:


ERROR: Source/WebKit2/UIProcess/Cocoa/WebViewImpl.mm:3163:  Missing space around : in range-based for statement  [whitespace/colon] [4]
ERROR: Source/WebKit2/UIProcess/Cocoa/WebViewImpl.mm:3175:  Missing space around : in range-based for statement  [whitespace/colon] [4]
ERROR: Source/WebKit2/UIProcess/Cocoa/WebViewImpl.mm:3185:  Missing space around : in range-based for statement  [whitespace/colon] [4]
ERROR: Source/WebKit2/Shared/mac/NativeWebGestureEventMac.mm:82:  Comma should be at the beginning of the line in a member initialization list.  [whitespace/init] [4]
Total errors found: 4 in 10 files


If any of these errors are false positives, please file a bug against check-webkit-style.

[Tim Horton]

http://trac.webkit.org/changeset/194125