Rotation with different axis does not work

[JulianBroudy]

Hello,

I am trying to migrate my code from the old Pt to this new library (Pts) and I am having some trouble.
More specifically, with the Pt's rotate2D or the Geom's rotate2D functions.

Good to know: before I illustrate the problem, I would like to add that since I was using the standalone file, in order to eliminate some possibilities I copied the standalone version that is currently public on the old repo and replaced it with my working pt.min.js and the Canvas didn't even load.
Conclusion: my version is different also from the currently released old one.
Here is a link to a gist with my version: pt.min.js.

Sample to replicate: (Tested in my own environment as well as in a demo editor)

(function() {

    /* Because I would like to have some more properties that 
       I will be using (not showing the usage here) */
    function MyPoint(thePoint, brightness) {
        this.thePoint = thePoint;
        this.brightness = brightness;
        this.direction = Math.random() < 0.5 ? -1 : 1;
    }

    var space = new CanvasSpace("#pt").setup({
        bgcolor: "#99eeff",
        retina: true,
        resize: true
    });

    var form = space.getForm();
    var mainPath = [new Pt(), new Pt(-Util.randomInt(20), 0)];
    let points;
    let pts;

    space.add({
        start: (bound) => {
            if (!points) {
                points = [];
                pts = [];
                for (let i = 0; i < 100; i++) {
                    var point = new Pt({
                        x: Util.randomInt(20) * i,
                        y: Util.randomInt(20) * i
                        /* The next line is my attemp to add 3rd coordinate */
                        // ,z: Util.randomInt(20) * i 
                    });

                    pts.push(point);
                    points[i] = new MyPoint(point, 0.7);
                }
            }
        },

        animate: (time, ftime) => {

            /* The following for loop and its alternative "Geom.rot..." work both 
               with and without the z coordinate, and it gives the same result: points rotate.*/

            // for (let i = 0; i < 100; i++) {
                // points[i].thePoint.rotate2D(Const.one_degree / 12, space.center);
            // }
            /* For's alternative */
            // Geom.rotate2D(pts,Const.one_degree, space.center);



            /* The following for loop and its alternative "Geom.rot..." does not create the 
               expected result whether I include the z coordinate or not! */

            for (let i = 0; i < 100; i++) {
                points[i].thePoint.rotate2D(Const.one_degree / 12, space.center, Const.xy);
                    /*OR*/
                //     points[i].thePoint.rotate2D(Const.one_degree / 12, space.center, Const.xz);
                    /*OR*/
                //     points[i].thePoint.rotate2D(Const.one_degree / 12, space.center, Const.yz);
            }
            // Geom.rotate2D(pts,Const.one_degree, space.center,Const.xy);
                /*OR*/
            // Geom.rotate2D(pts,Const.one_degree, space.center,Const.xz);
                /*OR*/
            // Geom.rotate2D(pts,Const.one_degree, space.center,Const.yz);


            let perpends = pts.map((p) => [p, Line.perpendicularFromPt(mainPath, p)]);

            form.strokeOnly("#123", 1).lines(perpends);
            form.fillOnly("#123").points(pts, 5, "circle");
            form.point(space.pointer, 10);
        }
    });

    space.bindMouse().bindTouch().play();

})();

To be clear, in the previous code, I am only trying to rotate it in 1 plane out of the 3 possibilities.

Expected result is what I have now with the old code and old pt.min.js:

Rotation on 2 planes at once

Rotation on YZ plane

Here is my current code with the old library and the pt.min.js I mentioned at the beginning.

I think the Const.xy don't get registered in the new library, possible?

Thank you.

[williamngan]

Hi @JulianBroudy , thanks for you detailed bug report. I tested your code and I believe there's a bug in Pts here:

https://github.com/williamngan/pts/blob/master/src/Num.ts#L368
(The $take function returns a new point and should update the original point)

I'll try to patch it in the next few days. Thank you again!

[JulianBroudy]

@williamngan hi,
Did you get a chance to take a look at that bug?

[williamngan]

Hi @JulianBroudy - Sorry about the delay. I've been so busy these days!

The bug should be fixed and patched in 0.9.2. I tested with your sample code and it seemed to work. Please give it a try and see if it works for you.

Thank you for reporting this bug and thanks for upgrading from Pt to Pts :D

[JulianBroudy]

Hi,
Thank you for that.

Does the Demo Editor include the fixed version?
If so, ignore the rest of the post because I tested it there.

I am getting some weird behavior, I am not sure if I am missing something maybe you could see it right away?

When enabling the following line:

            // Geom.rotate2D(pts,Const.one_degree, space.center,Const.yz);

(with Z point enabled) I instantly get this result:

Also, enabling only XZ plane seems to rotate points until they reach this stage and it stops there:

What am I doing wrong?
P.S., This can be replicated by using the same code I posted above in a Demo Editor and uncommenting the Z-coordinate. The results are same whether rotating using point.rotate2D() or Geom.rotate2D().

[williamngan]

Hi again @JulianBroudy - sorry it's my fault. I forgot about the array index here (8093b23)

It should be fixed now (version 0.9.4). I didn't test your code but I wrote some unit tests and it's working as expected. See if it works for you.

Thanks!

[JulianBroudy]

Hi,
I apologize for going MIA.
I took a brief look, looks like everything checks out.
Thank you very much.