Plot date on both axis

[karthiksd9]

I am trying to plot the milestone chart, i.e. the chart that plots date on doth x and y axis.
I am using the type: "time" for both axis to do it :

		var config = {
			type: 'line',
			data: data1,
			options: {
				responsive: true,
				title:{
					display:true,
					text:'Milestone Chart'
				},

				scales: {
				xAxes: [{
						type: "time",
						display: true,
						scaleLabel: {
							display: true,
							labelString: 'Time-X'
						}
					}],
				
				yAxes: [{
				        type: "time",
				        position: 'left',
						display: true,
						scaleLabel: {
							display: true,
							labelString: 'Time-Y'
						},
						
						time: {
						    unit: 'month',
						    unitStepSize: 4
						},
					}]
				},

				legend: {
				    display: true,
				    position: 'bottom'
				}
			}
		};

The problem is, Y axis date is displaying inverted. i.e. it doesn't start with lowest date.
It starts with end date and moves up to the start date.
Can someone please help me how to fix it.

here is the fiddle:
https://jsfiddle.net/ovw0rudn/2/

[etimberg]

To change the order, the ticks[] array needs to be reversed. Some of the other axes support this property already. I'm happy to merge a PR adding support for the reverse property to the time scale.

[karthiksd9]

@etimberg Thanks. Adding reverse property to the time scale would be really helpful.

[karthiksd9]

@etimberg How to reverse time scale in ticks?

[etimberg]

I think you would need to add some code after https://github.com/chartjs/Chart.js/blob/master/src/scales/scale.time.js#L310 that is similar to https://github.com/chartjs/Chart.js/blob/master/src/scales/scale.logarithmic.js#L157-L165

[karthiksd9]

@etimberg Thanks for the reply.
One quick question, Why the Y axis is plotting in reverse order? It should start from lowest date and end with max date right by default right? Just like x axis.

[etimberg]

@karthiksd9 I agree that it's supposed to draw like that, but I think it actually does drawing from the top and the ticks array isn't correctly reversed. Either that, or the getPixelForValue function is wrong for time axes that are vertical.

[karthiksd9]

Hi @etimberg ,
Any update on this Issue?

[nagix]

The reverse option support was added to time scale by #5927, and it is included in version 2.8.0.