This commit makes the size of the dot/sphere that represents particles
in the viewport consistent across screens with different DPI.
The shader was multiplying the particle's size (`gl_PointSize`) with
`sizePixel` which lead to particles being drawn bigger in relation to
the rest of the UI on screens with a higher DPI.
Instead the `draw_size` is now multiplied with `U.ui_scale` so the
particle's size still adapts together with the rest of the interface
when changing the global UI Scale.
|Display / UI Scale|1080p / 1.0|retina / 1.0|1080p / 2.0|retina / 1.0|
|---|---|---|---|---|
|**patch**|{F12864342}|{F12864345}|{F12864346}|{F12864347}|
|**master**|{F12864349}|{F12864351}|{F12864353}|{F12864354}|