Angle Constraint flawed in XDP X9

Angle Constraint works in an earlier version of Xara but (for example) 30 degrees constraint gives this in XDP X9:

Attachment 102338

Pretty but not what I want. There should only be 360/30=12 shapes rotated but in this image there are 28.

You're correct Sadler, for some reason with the contstraint set at 30 degrees, on rotation it snaps to 14.10, 30, 60, 75.80 & 90

Thanks for confirming that Egg. Note that it is not just 30 - almost any angle constraint doesn't. Also applies to earlier versions though was working as expected a few versions back. Perhaps it will be put straight before the imminent XX release.

Will it not simply be a feature of the number of control points a shape has?
If the object is a line, I get 12 x 30 degs.
With a random shape, I was getting 0.3, 20.3 30, 30.3 etc.

What I do is rotate the object using the right mouse button and watch the Angle window and left click on the required angle when the Ctrl key is held down.

Acorn

I thought this might be the cause initially Acorn, so to eliminate this possibility I placed the shape well within the confines of an outer circle and grouped the two, thus elimainting various control points as it was now a perfect circle. It showed the same error. The constraint was never 30, 60, 90 etc but some very odd angles.

View in HD

Thanks again for doing the vid Egg. Just to confirm - angle constraint works as expected without any fractional angles and with any shape and any centre in Xara PGD 7.

Yes that appears to be the case Sadler, it's a bug that's crept in on later versions. Personally I never use the constraint feature, prefering to type the required rotation angle into the rotation text box each time.

I tried it in xdpx

square: - works fine with both 30deg and 45deg
triangle: works with 30deg, but not 45 deg
above three point... starts to 'play up'

I think it has to do with where the centre of rotation is relative to the actual centre of the shape [as opposed to the boundary handles]...

But if this were the case, surely enclosing it within a circle and grouping ensures the centre of rotation is the centre of the circle?

don't know with version 9 egg I don't have it - just passing on the results I got with version 8 for the record

how did you centre the star in the circle? - using the alignment tool won't work, as that goes by boundary box [had a discussion about that earlier in another thread] - if it wasn't centred according to geometry rather than BBox, just grouping it might not be enough?

You may have well hit the nail on the head there handrawn. Reduced the shape to a very small amount within the circle. Centered, grouped and rotated & this time the rotations were in 30, 60, 90, etc stages. However having said that, this behaviour is fairly recent (perhaps to do with html files) but needs documenting.

Have you a link to the BB discussion?

her you go - basically Phil recommended using snapping rather than alignment:

http://www.talkgraphics.com/showthre...ht=#post505317

You, know this is maybe the first time, ever, that I have use angle constraint so I cannot say how far back it goes - I can check on xtreme 2 if anyone wants me too next time i am on my win 7 machine....

It is interesting to hear the Egg and handrawn have never user angle constraint. I use it ALL the time at home (PGD 7), just hadn't used it recently at work until now (XDP X9 64bit) not having much of a need for radial patterns at work.

But for me,

Ctrl+drag object centre to snap to centre-base of object
Ctrl+rotate while right-click to create duplicates

is quick and convenient workflow for lots of situations, not just radial patterns.

As for how far back - well the bug is not in 7 but is in 9.

I can't replicate this in Design Pro6 or PDG 2013 both work well without the grid turned on. Using Quick Shapes and star selected, 4 points right up to 8 only using the even numbers because of the 30 angle. The I did a square, a line and a butchered oval (petal shape) with the centre of rotation at the bottom and yes Sadler I am with you on this I always double click then use Ctrl + right mouse button click to duplicate and all worked well. So maybe the bug, if there is one is from D Pro 9 onwards but in my older programmes from 4 through to 6 and PDG all work correctly.

I just wanted to add that this same constraint option also applies to Ctrl+drag of objects so IMHO it is reasonable to assume that rotation constraint was broken when this feature was introduced and that the constraints were conflated, confusing the developer and the users (well, me at least) in the process.

From Pro X (v8)

Ctrl+rotate alignment
When rotating objects if you hold Ctrl down it now snaps any significant straight edge to the horizontal or vertical. This applies to text lines, columns and blocks, photos, Quick Shapes, lines and even freehand drawn shapes that have significant straight edges.

From v7

Non-axis aligned snapping
You can now also align to lines that are neither vertical or horizontal.