Viewport values should be clamped between 0 and 1

[biagas]

Describe the bug

If Viewport coordinates get set outside the values of 0 and 1, the view calculations for zoom (and possibly others) don't work correctly.

This was reported by customer. See discussion 20260

Reproducer:

OpenDatabase("rect2d.silo")
AddPlot("Pseudocolor", "d", 1, 1)
AddPlot("Pseudocolor", "p", 1, 0)
AddOperator("Reflect", 0)
SetActivePlots(1)
ReflectAtts = ReflectAttributes()
ReflectAtts.octant = ReflectAtts.PXPYPZ  # PXPYPZ, NXPYPZ, PXNYPZ, NXNYPZ, PXPYNZ, NXPYNZ, PXNYNZ, NXNYNZ
ReflectAtts.reflections = (0, 1, 0, 0, 0, 0, 0, 0)
ReflectAtts.reflectType = ReflectAtts.Axis  # Plane, Axis
SetOperatorOptions(ReflectAtts, 0, 0)

View2DAtts = View2DAttributes()
# set the max-x > 1
View2DAtts.viewportCoords = (0.2, 1.2, 0.15, 0.95)
SetView2D(View2DAtts)

DrawPlots()
ResetView()

Here's the plot before zooming with the border between the reflected and non-reflected plots at x=0

And after zooming, the border between the reflected and non-reflected plots has 'moved'.

When the 2DView values are set between 0, and 1, then the view after zooming is still correct.

Expected behavior

If the view calculations won't be correct if Viewport values are outside the range of 0,1, then they should be automatically clamped.

Desktop

• OS and version: [e.g. Ubuntu 14.04]
• VisIt Version: 3.4.2

[markcmiller86]

Do we understand what @awcook was trying to achieve with setting the high X value of the viewport to above 1? It may have been inadvertent entry from previous fiddling. However, I feel like we should understand what lead the user to setting that and whether the setting had some positive effect in another way.

That isn't to suggest we should allow values outside [0,1]. But, maybe we need settings elsewhere that give the user the control they were seeking.

FYI...I don't see oddities without some kind of an operator in place...Reflect or Transform or something. If I just have a 2D database open and a PC plot up, as I fiddle with viewport values above 1, I don't see view change in any way. But, if I use Transform to rotate or Reflect then a see substantial changes in view as I vary high X value of viewport above 1.

[biagas]

@awcook set the viewport in the manner he did to make his movie look good in widescreen format.