[vtk-developers] [VTK 0016034]: OS X conversion of track pad scroll to MouseWheel events

[Mantis Bug Tracker]

The following issue has been DELETED. 
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Reported By:                David Gobbi
Assigned To:                David Gobbi
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Project:                    VTK
Issue ID:                   16034
Category:                   (No Category)
Reproducibility:            have not tried
Severity:                   minor
Priority:                   normal
Status:                     backlog
Project:                    TBD 
Type:                       incorrect functionality 
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Date Submitted:             2016-03-21 08:12 MDT
Last Modified:              2016-03-21 08:16 MDT
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Summary:                    OS X conversion of track pad scroll to MouseWheel
events
Description: 
The vtkCocoaNSView class does not correctly handle scroll wheel events.

Currently, the code simply emits one VTK MouseWheelEvent for each scrollWheel
event, without regard for the actual size of the deltaY for the scrollEvent. 
The result is very jerky interaction.

To fix the interaction, the deltaY should be accumulated until it reaches a
value of 120 (which corresponds to one "click" of an old-style mouse wheel), at
which point a VTK MouseWheelEvent should be invoked.

Since OS X 10.7, an additional property called scrollingDeltaY is available.  I
don't know if this offers advantages over simply using deltaY, but it should be
investigated.  My feeling is that deltaY is the best property to use.
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Issue History 
Date Modified    Username       Field                    Change               
====================================================================== 
2016-03-21 08:12 David Gobbi    New Issue                                    
2016-03-21 08:12 David Gobbi    Assigned To               => David Gobbi     
2016-03-21 08:16 David Gobbi    Description Updated                          
2016-03-21 15:16 David Gobbi    Issue Deleted: 0016034                       
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