rect collisions don't account for rectMode

[teacher-svb]

When rectMode is set to CENTER, collision with a rect still acts like it is drawn from the top-left.

[teacher-svb]

I see in the code comments that there is already a mention for this issue.

this._renderer._rectMode

this gets you the current renderer/canvas, en allows you to find the rectmode currently in use.

[bmoren]

Yes this is a known issue/feature, thanks for bringing it up :)

It's one that is somewhat parallel with the rotation issue (#46) and could be solved by looking at the state of the render in p5 at large. This has the benefit of 'it just working' when the rectMode(), ellipseMode(), imageMode() etc are changed.

Although the downside is that if you're not working with matched geometry and output (eg. a hitbox that does not correlate directly to the visual element rendered) then you might end up in a reverse situation where you're trying to 'correct' the hitbox back to 'normal'

On example of this is if you had an image (rectangular) and it had a elliptical picture inside of it that you wanted to have collide using the collideEllipse function. if we make the assumptions about the modes, it can easily become a situation where things become mis-aligned – eg. imageMode causes the rect(?) collide function to move it's center/cornder coordinates and the ellipse collide function's coordinates are not manipulated because there is no call to ellipseMode() (?).

I'd love to hear ideas or thoughts about these kind of scenarios before working on an implementation. You're correct that there is reference to it. I did think about adding it right at the beginning of this lib, but I ended up holding back as I thought it would ultimately add more confusion having things magically move based on the rendered or a second setting, but I'm totally open to re-opening the discussion!

To kick this idea off – When I was thinking about this I settled on thinking about the collisions as its own set of sort of 'shadow geometry', and as such it could have it's own mode which would reset everything. Something like collideMode() which would set all geometry based collisions to function with offsets to account for the mode change.