I've encountered a problem with the new 'Set Canvas Size' and low quality fullscreen scaling functionality in r156. I'm assuming that it works by setting the pre-stretch render scale with the layout scale expression? This works fine for regular letterbox scale but I get inconsistent results when I try to use it with letterbox integer scale.
For instance, multiplying game resolution 340x236 with 3 gives 1020x708 which is a close match to a target screen resolution of 1024x768. So for screenres 1024x768 the Letterbox Integer Scale will multiply the game resolution with 3. All good. But for some reason, it won't do the same if I set canvas size to 680x472 and layout scale to 2.0, or anything above 552x384 really. In that case, it'll stretch everything up to 2x size instead of 3x. However if I run a higher screen resolution like 1600x1200 both settings get scaled up to 4x.
Is this a bug? It doesn't happen at all with regular Letterbox Scale.
Screen resolutions that stretch canvas size 340x236/680x472 with layout scale 1.0/2.0 to the same size:
1600x1024
1600x1200
1920x1080
Screen resolutions that stretch canvas size 680x472 with layout scale 2.0 one increment less than they should (for instance 3x when it should be 4x):
1024x768
1152x864
1280x1024
1366x768
1600x900
1920x1200
Hope my explanation is clear here :P