Add additional parameter to orbitControl to enable/disable inverted vertical rotation

[dekmm]

Nature of issue?

• Found a bug
• Existing feature enhancement
• New feature request

Most appropriate sub-area of p5.js?

• Color
• Core/Environment/Rendering
• Data
• Events
• Image
• IO
• Math
• Typography
• Utilities
• WebGL
• Other (specify if possible)

Feature enhancement details:

As mentioned in PR #2956 I was thinking of adding an additional parameter to orbitControl to enable/disable inverted vertical rotation. The linked PR currently changes the inverted rotation in orbitControl, that was supposedly incorrect, to normal rotation. Knowing some users actually prefer inverted vertical rotation, adding a flag to control this would be helpful.

[Spongman]

how about adding two parameters scaleX and scaleY with default value 1? making either of these negative would change the sense of the rotation, and adjusting the magnitude would change the sensitivity.

[dekmm]

I like the approach. Would 1 be considered the maximum allowed sensitivity so it ranges from -1 to 1 or is it just an agreed upon starting point?

[kjhollen]

Thanks @dekmm! @AidanNelson is one of our Google Summer of Code students for p5.js and part of his project is improving the camera API and interactions for Web GL mode. Is it ok with you if I assign this issue to him?

[Spongman]

I don't see the need for a setting a maximum. If someone wants to make it more sensitive than normal, it should probably allow that.

[dekmm]

@kjhollen go ahead!

[AidanNelson]

Two questions:

1. It looks like orbitControl() expects angleMode to be RADIANS, but doesn't explicitly set angleMode in the function. I can add this check, but am wondering if I should file it as a separate issue for organizational purposes?
2. If the user specifies a scaleX and scaleY, does it make sense for those values to override the width-dependent scaling or modify it? I'm inclined to think that overriding those values adds more flexibility for the user (who can always pass width/2 * scaleFactor in as the scale factor). That said, I think there should be some scaling such that users can pass in values from 1-10, so maybe that scaling should just be width/2. Thoughts?

[Spongman]

1. you can use _fromRadians to convert from radians to angleMode, if necessary.
2. i'd recommend coming up with some sensible default scale factor that you think makes sense, and then just multiply that by any scale factors that are passed in.

[kjhollen]

closing because the fix for this has been merged into webgl-gsoc-2018!