[webkit-changes] [WebKit/WebKit] 2fc837: [UnifiedPDF] Can't zoom out below scale 1

[Simon Fraser]

  Branch: refs/heads/main
  Home:   https://github.com/WebKit/WebKit
  Commit: 2fc8377fb2908ec7003d3e8591aa5a418bfdcf54
      https://github.com/WebKit/WebKit/commit/2fc8377fb2908ec7003d3e8591aa5a418bfdcf54
  Author: Simon Fraser <simon.fraser at apple.com>
  Date:   2024-01-29 (Mon, 29 Jan 2024)

  Changed paths:
    M Source/WebKit/UIProcess/ViewGestureController.cpp
    M Source/WebKit/UIProcess/ViewGestureController.h
    M Source/WebKit/UIProcess/WebPageProxy.cpp
    M Source/WebKit/UIProcess/WebPageProxy.h
    M Source/WebKit/UIProcess/WebPageProxy.messages.in
    M Source/WebKit/UIProcess/gtk/ViewGestureControllerGtk.cpp
    M Source/WebKit/UIProcess/mac/ViewGestureControllerMac.mm
    M Source/WebKit/WebProcess/Plugins/PDF/PDFPluginBase.h
    M Source/WebKit/WebProcess/Plugins/PDF/UnifiedPDF/PDFDocumentLayout.mm
    M Source/WebKit/WebProcess/Plugins/PluginView.cpp

  Log Message:
  -----------
  [UnifiedPDF] Can't zoom out below scale 1
https://bugs.webkit.org/show_bug.cgi?id=268310
rdar://121866624

Reviewed by Tim Horton.

For the PDF plugin, we need to allow minimum zoom scales of less than 1. Add support
for this by allowing the plugin to vend min and max scales, keeping track of them
in WebPageProxy. ViewGestureController reads them from there.

We compute the min and max elastic zoom scales relative to the min and max,
using multipliers that gives the same results as the old hard-coded values.

The PDF min and max scale values match those in PDFKit.

* Source/WebKit/UIProcess/ViewGestureController.cpp:
(WebKit::ViewGestureController::endMagnificationGesture):
* Source/WebKit/UIProcess/ViewGestureController.h:
* Source/WebKit/UIProcess/WebPageProxy.cpp:
(WebKit::WebPageProxy::minPageZoomFactor const):
(WebKit::WebPageProxy::maxPageZoomFactor const):
(WebKit::WebPageProxy::mainFramePluginHandlesPageScaleGestureDidChange):
* Source/WebKit/UIProcess/WebPageProxy.h:
* Source/WebKit/UIProcess/WebPageProxy.messages.in:
* Source/WebKit/UIProcess/mac/ViewGestureControllerMac.mm:
(WebKit::ViewGestureController::resistanceForDelta):
(WebKit::ViewGestureController::handleMagnificationGestureEvent):
(WebKit::ViewGestureController::didCollectGeometryForSmartMagnificationGesture):
* Source/WebKit/WebProcess/Plugins/PDF/PDFPluginBase.h:
(WebKit::PDFPluginBase::minScaleFactor const):
(WebKit::PDFPluginBase::maxScaleFactor const):
* Source/WebKit/WebProcess/Plugins/PDF/UnifiedPDF/PDFDocumentLayout.mm:
(WebKit::PDFDocumentLayout::layoutSingleColumn):
* Source/WebKit/WebProcess/Plugins/PluginView.cpp:
(WebKit::PluginView::initializePlugin):

Canonical link: https://commits.webkit.org/273725@main