Hi I am trying to make a simple text element scroll across the screen, however, quite often it looses the smoothness to the animation and looks a bit jerky, the attached video the effect is not as bad as I have observed, however, even this lack of smoothness is a big problem for me, is there a fix for this?

the attached comp does have a test and only scrolls if the string is longer than a certain length, however the cpu load is around 20% so I can't understand why its glitching like this...

thanks for your help!

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Same for me.

Bodysoulspirit's picture
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Same for me.

Smooth text scrolling was already a subject in QC, I remember one guy that found a workaround using Java code to smooth scroll.
Made a simple composition, not smooth for me neither, actually it seems the text is smoother with the original window size, gets worse when I resized it (not even sure).
Even turned off multisampling.
This happens for big texts but also with smaller font sizes.

My HD 3000 is old but I would hope recent Macs would handle this.
It runs at 59/60 FPS though and the cpu load is low too.
Tested in Vuo 1.2.6

Does this happen for all Macs ? Or would @grahamis his GPU fallback some graphics to the CPU too like the HD 3000 bug and be the cause for non smooth text scrolling ?

Vids and composition below

Aha, looks like the issue is

jstrecker's picture
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Aha, looks like the issue is not graphics slowness, but a side effect of the way that Make Text Layer renders sharp text.

Make Text Layer snaps the text to pixels so that it's totally sharp rather than blurred across pixels. However, as your composition points out, this can interact weirdly with scrolling text across the window. To keep the text sharp, Make Text Layer causes the text to jump from one pixel to the next. Depending on how the scrolling events line up in time with pixels in space, the text could actually move 1px or 2px or 0px on a given display refresh. Hence the jerky motion.

If you remove Make Text Layer and just use Make Text Image — which, when combined with Make Image Layer non-realsize, does not snap to pixels — that should be smoother. With the attached composition, if you slow down the scrollers and zoom in, you can see the pixels gradually fade in and out as it moves along.