Comment 20 for bug 722285

Ok, but even if this is the case (old Cairo/Goocanvas, 16 bits integer + 16 bits decimal), there the comfortable 16-bit decimal part encompasses a range from 0000 to 9,999 (but not to 99,999). Combined with the integer part, one can go from 0.0000 to 65,535.9999 which represent 65,360,000 distinct values.

Assuming that a desired time-line precision would be 1/100 sec, old Goocanvas/Cairo should be able to accommodate a time-line of 653,600 seconds, which is ... 1820 hours !!
And even if one wanted to go for a 1/1000 sec precision, old Goocanvas/Cairo would accommodate a time-line of 182 hours.

So maybe it's all about using that decimal part, with an appropriate canvas-to-time ratio??