Scale apply... Where can be usefull not applying the scale?

(Piton812) #1

Hi! Can somebody explain me what the reason of the function “applying the scale”? I mean why the scale is not applying automatically? why should we remember about this all the time? is there is the usefull reason about that? For now I modeling the exact project of the flat and I start to measure the distance of the objects… and I forget to apply one of them and when I measure it instead of 60 cm it was about 30 cm… after applying the scale everything was ok, but it’s confusing any way… I still don’t understand why should we remember all the time about to applying the scale… where not applying the scale can be usefull?

(JA12) #2

It’s about the difference between objects in object mode, and object data in edit mode. The object may have transforms that differ from the defaults, but then you’re not looking at the object data the way tools and modifiers see it because of the object level transforms. In case of scaled object, the dimensions don’t match, and if the scale is also non-uniform or negative, the tools seem to give skewed results, or go in the wrong direction because the whole thing is flipped inside out. When modeling, you want the object level transforms to be the defaults so what you see is what you get. If they’re not, you need to apply them first. Rotation and scale are more important, location just puts the origin to world origin. Object data can be shared between objecs, and object level transforms can be animated, yet it’s still possible to edit all of them because the separation between the two. One practical example of that is to put many screws around an object, even different size ones, and still be able to edit all of them. If you take one and reset the object transforms instead of applying them, it’s possible to edit it and still make sense of the modifier settings and have tools give predictable results. Although, you would be better off using instances instead of linked duplicates, but still valid example and it’s possible to turn the duplicates into instances. That’s probably best left for another thread though.

(FinalBarrage) #3

A good explanation.

Another practical example for rotation would be when modelling mechanical things. Its easier to model them when they’re aligned with an axses, but you might want to put it at an angle to fit with everything else.

In this case, you can quickly reset the rotation, edit it, and rotate it back.

As for scale, i havent found many practical uses for this, as i dont tend to link object data as JA12 mentioned. But i do use it form time to time, and would rather have it, than not have it.

Worst thing that can happen from my experience is that modifiers dont act correctly, in which case i apply the scales and fix the values in the modifiers.

  • If tools break, its pretty obvious, and a quick fix.