Feature Request: Make plotly_click events in 3d plots consistent with 2d

[CmpCtrl]

There are some issues/limitations with the 3d plot events, particularly the click event, that aren't present in the equivalent 2d plots. It would really help their functionality to be consistent with the 2d events.

I've been working specifically with scatter3d (or surface) plots and the plotly_click event.

My biggest issue is that the plotly_click event is fired on mousedown (in a 2d scatter it is fired on mouseup). That makes it impossible to tell if the user is intending to select a point, or to click and drag to rotate/pan/zoom, etc. That is an issue since typically a callback related to selecting a point conflicts with a drag to rotate operation. Again, the 2d scatter behaves as intended.

Here is a simple demo, the click events are logged to the console, you'll note that in the 2d scatter, click and drag (to zoom) does not fire a plotly_click event, but doing the same thing in the 3d surface plot does fire the ploty_click before the drag functionality.
https://codepen.io/cmpctrl/pen/rNJLNLd

One thing i hoped to use to workaround this issue was to detect if the user right clicked on the plot. Unfotunately, the DOM MouseEvent data that is, very usefully, included in the 2d click_data is missing in the 3d plots.

Similarly, there is no plotly_doubleclick event for 3d.

Some related issues, there may be more.
#2565
#3266
#5590

[CmpCtrl]

I did a little more digging and it seems like it won't be easy to add the DOM MouseEvent data to the eventData but it should be relatively easy to add some more data to it, which at least would help with detecting which button is clicked..

I think the relevant section is here:

plotly.js/src/plots/gl3d/scene.js

Lines 403 to 420 in 12a49c0

	var pointData = {
	x: selection.traceCoordinate[0],
	y: selection.traceCoordinate[1],
	z: selection.traceCoordinate[2],
	data: traceNow._input,
	fullData: traceNow,
	curveNumber: traceNow.index,
	pointNumber: ptNumber
	};
	Fx.appendArrayPointValue(pointData, traceNow, ptNumber);
	if(trace._module.eventData) {
	pointData = traceNow._module.eventData(pointData, selection, traceNow, {}, ptNumber);
	}
	var eventData = {points: [pointData]};

What about adding something like the following? Any other useful tidbits we could include here?

var eventData = {
    points: [pointData],
    buttons: selection.buttons,
    distance: selection.distance,
};

Then it seems like the plotly_click event could be moved from here, which happens at the start of a click and drag.

plotly.js/src/plots/gl3d/scene.js

Lines 450 to 465 in 12a49c0

	if(selection.buttons && selection.distance < 5) {
	gd.emit('plotly_click', eventData);
	} else {
	gd.emit('plotly_hover', eventData);
	}
	this.oldEventData = eventData;
	} else {
	Fx.loneUnhover(svgContainer);
	if(this.oldEventData) gd.emit('plotly_unhover', this.oldEventData);
	this.oldEventData = undefined;
	}
	scene.drawAnnotations(scene);
	};

While i was looking at this, i also noticed that the plotly_unhover fires at every step of a click or drag, which doesn't seem helpful. Perhaps that could be addressed at the same time.

Something like the following? This is completely untested...

        if (!selection.buttons && !selection.distance < 5) {
            gd.emit('plotly_hover', eventData);
            this.oldHoverState = true;
        }

        this.oldEventData = eventData;
    } else {
        Fx.loneUnhover(svgContainer);
        if (this.oldHoverState) {
            gd.emit('plotly_unhover', this.oldEventData);
        }
        this.oldHover = undefined;
        if (this.oldEventData && this.oldEventData.buttons && this.oldEventData.distance < 5) {
            gd.emit('plotly_click', this.oldEventData);
        }
        this.oldEventData = undefined;
    }

    scene.drawAnnotations(scene);
};

I hesitate to try to make a pr for this since i have almost no experience with js and dont feel like i understand it well enough to make a reliable change. Can i just add this.oldHoverState like that? or does that need to be defined elsewhere?

[gvwilson]

Hi - we are trying to tidy up the stale issues and PRs in Plotly's public repositories so that we can focus on things that are still important to our community. Since this one has been sitting for several years, I'm going to close it; if it is still a concern, please add a comment letting us know what recent version of our software you've checked it with so that I can reopen it and add it to our backlog. Thanks for your help - @gvwilson