Slope arrow block - ViewTwist when Plotting

[kostial.mk]

Hi everybody,

I have a slope arrow block that uses formula field to calculate slope, I attach the block. The formula uses Block rotation and ViewTwist to calculate the slope relative to current view rotation. I use Grads as angle units, the formula is adapted to that. 

The problem with this is, that when printing on plotter, the paper is "virtually" rotated by 90°. Therefore the field seems fine when working in modelspace/paperspace, but when plotting (even in preview) the value is wrong. Plot to PDF gives the correct values.

 To prevent this I set the FieldEval variable to 27 - not to update fields when printing. But I wonder if there is some other, better way. Perhaps somehow get the "PlotTwist" value or using completely different approach. I would prefer changing the block, not changing the plotter settings.

Thank you in advance!

[Libbya]

Do you need the 'viewtwist' as part of your field formula?  That is what is skewing the result.  

[kostial.mk]

Actually I do.

1. Often I do have multiple viewports with different UCS and view.

2. Our drawings are always in state coordinate system. When we make a detail drawing for a certain object within the construction site the plan viewport UCS is rotated from world UCS. The cross sections and views are parallel to the plan. The block rotation parameter is relative to world UCS, not the current UCS, therefore the field value was not correct.

That was the reason, the ViewTwist got there in the first place. If there is some other way to get the slope value relative to current UCS, I am willing to change the formula I've got.