I cannot seem to get the canvas rotate transform to work, can someone provide a brief example so I can how it works, thanks.
Are you working on the speed-o-meter?
canvas rotations really mess with my head because they happen about the top left corner by default
So typically you might do a translation to move the center of rotation
then rotate
then undo the translation
then draw the object
And then continue the above pattern
I once wrote an app in anvil - using anvil’s canvas that had a similar feel to a speedometer:
And I didn’t use rotate.
Instead I used some maths to work out exactly where the position was in the x,y plane based on the radius and the angle.
It made my head explode less 
But then I’ve been a maths teacher so… yeah.
You can see the basic approach here for drawing two rectangles (one of which is rotated)
and converted code to python/anvil
https://anvil.works/build#clone:NNSQVJYVMRPMVDO4=QFJPVA3FLNMCCV5OEA55DLOF
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I am working on the speedometer. I’ve considered ceating a canvas that is precisely a certain size and then doing the math to figure out what a particular angle would be but… I cannot afford for my head to explode.
I know that plotly polar indicators is the way to go but I could not figure it out in time.
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