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Strange behavior of TPads drawing on M1 Mac

Recently I’ve bought a MacBook Air with an M1 chip and installed ROOT from the source. Everything seems to work fine except for one issue I’ve stumbled upon:
When I use TCanvas with manually set TPads, I have some glitches when trying to save it.

I’ve attached the test code to illustrate the situation. The First 2 canvases are saved fine, but the third one where I use TPads has some problems - I’ve attached them below.
No errors or warnings are showing up during the macro execution, so I don’t know what causes this issue and how to solve it.

First canvas:
test_hist_canv1.pdf (15.0 KB)
Second canvas:
test_hist_canv2.pdf (17.2 KB)
Third canvas:
test_hist_canv3.pdf (21.7 KB)

The code, producing canvases:
Draw_test.C (1.9 KB)

_ROOT Version:6.22/09

@couet can you please take a look whenever you will have time? Thank you!

I see the 3rd one shows a black background. I need to try on an M1

on M1 I get:

The outcome of the third canvas depends on whether root was used in batch mode or not.
I’ve got mine canvas by using root -l -b -q Draw_test.C
The latter one is probably obtained by root -l -q Draw_test.C
Even then, the canvas has some strange black lines around TPads.

On M1 there is this problem with default parameters. It affects the default colour of the pads. You can try to not rely on the default colour (ie: specify it) to see if it cures the problem.

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Setting the colors specifically doesn’t work, but I’ve recompiled ROOT with the commit resolving the problem and it fixes this issue.
Thank you for the help!

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