mltframework
Preview scaling very inaccurate with multi-line text
Shotcut Windows 10 64bit - version independend (presumably)
Observed in the Text: Simple filter - didn't check others
Steps to reproduce: 1.) Create a 1080p project with a clip and apply Text: Simple filter. 2.) Enter 10 lines of text 3.) Turn on preview scaling 360p Result: Last line of text is shifted up by more than one line.
Note: there are severeal other minor inaccuracies with preview scaling in various filters - however nothing neraly that obvious AFAIK.
I think I only reproduce this when "Use font size" is enabled and a small enough font size such that the text does not completely fill the rectangle. I write "think" because it depends on what you mean by "line" - pixels or text? Preview scaling as implemented is inherently inaccurate, and I do not know how to fix that in general. If someone figures out a way to do it that still provides the performance benefit (i.e. does not first render to project resolution and then downscale), then it will be a complete rewrite. Unfortunately, I have not found a way to fix the reported problem due to this design.
I actually mean one whole line of text. I can provide screen shots of my exact settings and their result if needed - it will just take some time since I don't have access to my shotcut projects right now.
I have created a small test project for this issue: The folder also contains two sample screenshots, one with and one without preview scaling.