Bug 60916 – Plug-in hit testing is broken after zooming

• Component: Layout and Rendering
• Status: RESOLVED FIXED

[Chris Marrin]

After zooming, events on plug-ins have the wrong coordinates, which means that plug-ins don't hit-test correctly.

You can see this on the video on nytimes.com

[Chris Marrin]

Created attachment 93688 [details]
Patch

[Simon Fraser (smfr)]

Comment on attachment 93688 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=93688&action=review

Would be nice to have a testcase, which should be possible with the test plugin and CSS transforms if the code were more general.

What about WebKit1?

> Source/WebKit2/WebProcess/Plugins/PluginView.cpp:579
> +        float scaleFactor = frame()->pageScaleFactor();
> +        WebMouseEvent webMouseEvent(static_cast<const WebMouseEvent*>(currentEvent), scaleFactor);

It would be nice to make this work in more general way which worked with CSS transforms.

> Source/WebKit2/WebProcess/Plugins/PluginView.cpp:648
> +    // Adjust bounds to account for pageScaleFactor
> +    float scaleFactor = frame()->pageScaleFactor();
> +    frameRectInWindowCoordinates.setX(frameRectInWindowCoordinates.x() / scaleFactor);
> +    frameRectInWindowCoordinates.setY(frameRectInWindowCoordinates.y() / scaleFactor);

Ditto.

[Darin Adler]

Comment on attachment 93688 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=93688&action=review

r=me

> Source/WebKit2/Shared/WebMouseEvent.cpp:81
> +WebMouseEvent::WebMouseEvent(const WebMouseEvent* event, float pageScaleFactor)

I suggest using a reference rather than a pointer for the event type.

> Source/WebKit2/Shared/WebMouseEvent.cpp:85
> +    , m_globalPosition(m_position)

I believe you can write:

    , m_globalPosition(m_position + (event->globalPosition() - event->position()))

And then avoid the code below that calls the move function.

> Source/WebKit2/WebProcess/Plugins/PluginView.cpp:579
> +        WebMouseEvent webMouseEvent(static_cast<const WebMouseEvent*>(currentEvent), scaleFactor);

I think this local needs a better name. The current event is also a web mouse event. How about eventWithScaledCoordinates?

[Chris Marrin]

Committed r86615: <http://trac.webkit.org/changeset/86615>