The custom mask has to be user defined because while it is possible to automatically generate a pixel-perfect mask, it would be incredibly wasteful on the CPU. If you just click the approximate shape by a custom mask, it is much faster than an automatic mask, and probably closer to what you want as well.
For one, the custom mask is already very frustrating to use, not the least of the reasons being that I can't edit it afterwards and there doesn't seem to be a zoom for any precision. For two, if an object happens to have a quarter circle in it or something along those lines, what do I do about that? Actual games apparently don't have any difficulty doing these things, so why should construct?
As for straight lines only - that's just the way it is - straight lines are fast to process.
o that's it then? "It won't do it because if someone chooses to do it this way the system requirements for their game will go up and therefore nobody must be able to do anything remotely useful as long as it takes processing power"? I've already had this argument before and it makes no sense, since you're so into using pixel shaders and all that fancy stuff but you're not into anything actually useful in creating games. I prefer functionality over gimmicks.
As for different animation frames - that's true, there's currently no way to do that. But it's tricky - if you switch to a different animation frame with a different mask, which results in the object being stuck halfway through something else, what do you expect to happen?
hen whoever made it that way just do it properly. I don't see why we shouldn't have to deal with design bugs we create on our own.
You missed the multiple mask bit that I mentioned but i'll assume it was the one thing you didn't object to.