Posted by mon

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These days, I am paying attention to make my notation as uniform as possible.
I feel like writing "bug" rather than "aberration"[word he usually uses for bugs, somewhat uncommon] or "collision detection" rather than "contact detection", but it's already too late. [for changing to the more commonplace words, presumably, seeing how he used the respective others up to know and wants to stay uniform]

Constantly flogging my unmotivated body into obedience, I idly poke around while looking at the wishlist.
An "illustration of collision('contact') detection" is there, but I thought that if I illustrated it from the point of view of the actual algorithm used for that, it wouldn't come over as particularly believable anyway.
...and wound up giving it a shot anyway, the result being this:

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[first image]
Chasing laser, ion ring, burner, bullet.
The collision detection fundamentally being based on distance measurement from circles and lines, they assume a rounded shape.
The reason for a part of the chasing laser's head being interrupted is that the afterimage is only created every two frames.
The reason why I thought this wouldn't be particularly believable and therefore unnecessary is image offset and that that this doesn't represent the collision areas in a way that's faithful down to single-pixel level.
Hence, those detection illustrations may not be seen as anything more than mere approximations.
Furthermore, since the player also has a size attribute, those might or might not hit depending on the type.
If the player's size value is set to 0 in the editor, this becomes the same size as bullet hell.

[second image]
Ripple.
Unlike the others, this is an elliptical shape.
When trying to illustrate it, I noticed there was a problem in the detection algorithm - the collision detection with the diffuser (defuser?) was acting up.
I should have fixed it in the appropriate manner... ellipses are a hassle and hard to pull off.

[third image]
Blade.
There only is collision for one frame's worth of afterimage.
In reality, this afterimage, too, has thickness (presumably referring to the +distance thing that made the lines in the original rounded and all), but drawing it was too complicated and so I simplified it.

[fourth image]
Barrier.
This being a slightly special circle, it was unexpectedly difficult.
There was a bug with this too, so I fixed it.
I suppose that, in the end, I can be happy having found a couple of bugs the one way or other.

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