How to display scale as time unit integers?

[clickworkorange]

I'm completely new to Vega-Lite and a little overwhelmed by the complexity, so please forgive me if this is a silly question! I'm plotting parameters for a process which runs from time 0 to some arbitrary time, say 4500 minutes. I would like to display the time axis with just an integer shown for each hour, converting the "minutes from start" value into whole hours (i.e. just 0,1,2,3...73,74,75). Setting the axis type to ordinal gets me pretty close, but unfortunately removes any gaps in the data, so a measurement taken at 615 minutes appears right next to one taken at 126 minutes when there are no in-between data points. I need the axis to be evenly spaced from the first measurement to the last. I've perused the official documentation which is excellent and voluminous, but I've failed to locate an answer. Every single example I've found deals with time as an actual date, which is not relevant (or even available) for my data, as it only deals with time as a unit of, well, time. Perhaps my use-case is just too weird? Grateful for any advise!

[clickworkorange]

I found a solution, by surrendering to the time lords and passing a UTC time as the value for the x axis (as time passed from 2012/01/01) and formatting the x axis thusly:

    x: {
    	field: "time", 
    	type: "temporal",
    	timeUnit: "hoursminutes",
    	title: "Hours from start",
    	axis: {
    		tickCount: "hours",
    		labelExpr: "[timeFormat(datum.value, '%H')]"
    	}
    }).

The key was finding labelExpr and timeFormat in the axis documentation - and... tada!