[SOLVED]question about rotate transform

[nananame]

I'm playing around with rotate and have a problem I can't wrap my head around.

This is the transform:

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transform turnit:#rotates image
    linear 1 rotate a+36##rotate through 1 second

The image is shown first time like so:

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show image:
    rotate a #a is default a = 0

This is the part which modifies a and b and shows the rotation:

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show image at turnit
$a+=36

Simple. The image is shown at the last position (rotate a), whenever the button is pressed it runs the transform (turning it by 36) and setting a to a+36. Work great.
the problem is if I start at somewhere other than 0. For example a=180. The image is shown correctly but when I turn it it jumps strangely for the first turn and then continues normally.

This is when starting from 0 - it works quite nicely. I end it at 180 (so number 5 is on top)


This is when starting from 180. Notice how it "jumps" then continues normally. Please be aware the calculations remains as it should. So if I click to rotate once the image will jump and appear to be at number 9 on top. But it will actually be at 216 degrees (a) and once I come back show 6 on top as meant to be.



So the problem is the first rotation if starting from other than 0. I tried inserting "rotate a" as starting position to the transform as well but it didn't work. Can anyone pplease enlighten me as I am losing my mind here

[hell_oh_world]

Not really helpful, but if you want to make the rotation appear smoother and not jagged, enable `subpixel`

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transform turnit:#rotates image
    subpixel True
    linear 1 rotate a+36##rotate through 1 second

[MaydohMaydoh]

Can't seem to reproduce this problem, but the only thing I can think of trying is increasing a before running the transform:

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transform turnit:
    linear 1 rotate a
    
$ a += 36
show image at turnit

Whether that would work or not, I have no idea.

[gas]

In fact even the first picture jump... it jump of 0 degrees .

How the code is done is that you linked the rotation to a global variable.
You show the image unchanged, then rotated by the delta of previous a, then again linearly by the final amount.

I suggest you to avoid globals. Use local variables instead.

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transform turnit(deg):
    linear 1 rotate deg

show pin at turnit(35)

That 'should' do the trick. Set the amount of degrees to rotate. If you want to keep the value (like, for example, a score or a datetime) use another variable.

[nananame]

Thank you everyone for your attempts. None of these worked
However, I figured out it's the fact that the transform rotation always believes to be at 0 when starting, and if I push him something else to start from it will rotate the image again (when it is already rotated!). I might have a hard time explaining it but in the end I simply had to find how much I rotated the images previously and then take that into ccount when doing the new rotation. Math to the rescue!