Set text size relative to canvas, not pad

[mwilkins]

Text size is, by default, set relative to the pad. This can cause the font size to differ across pads of different sizes drawn on the same canvas. Is there a way to cause all pads to use the same font size? Or to specify that they should be determined relative to a certain canvas instead of the pad? Reproducer below.

---

import ROOT as r
h = r.TH1F("h", "h", 100, -10, 10)
h.FillRandom("gaus")
c = r.TCanvas()
p1 = r.TPad("p1", "p1", 0, 0.3, 1, 1)
p2 = r.TPad("p2", "p2", 0, 0, 1, 0.3)
p1.cd()
h.Draw()
p2.cd()
h.Draw()
c.cd()
p1.Draw()
p2.Draw()
c.Update()

[couet]

If you use the font precision 3 you can specify the font size in pixel.
There is many examples on the forum.