How to calculate the height of a FontFamily with Win2D (Line Spacing)?

Question

I would like to know how to calculate the height of a given a font (with its properties, like size, weight, style...) in a Window Universal Application using Win2D.

I previously used a CanvasTextLayout, but it requires a text to work, like in this line:

var ctl = new CanvasTextLayout(session, "Some text", new CanvasTextFormat(), constraintWidth, constraintHeight);

In my case, I will NOT have a text because what I'm looking for is the height in which all the glyphs of a given font (with its style, size, weight...) are fit.

EDIT: I have also tried with the CanvasFontFace class, but it seems it doesn't have any public constructor.

Deviled

Are you looking for GetGlyphRunBounds microsoft.github.io/Win2D/html/… ? otherwise CanvasTexFormat has a FontSize property, as usual with font families – Peppery

I think GetGlyphRunBounds is not what I need, since I would have to specify at least one glyph. It's the exact equivalent to this question, but in Win2D. #4510113. Please, see the answer. In WPF it's call "LineSpacing". – Deviled

I don't think you can get the default LineSpacing like in WPF. You will have to draw the text first. This is a limitation of Win2D. – Hobgoblin

Ok, now the question is clear :). CanvasTextFormat has a LineSpacing property: microsoft.github.io/Win2D/html/… – Peppery

It has the property, but it's always -1. I think it's not what we are looking for :( – Deviled

Answer 1

But you are already on the right way. Use e. g. fg as text. The f allocates the upper area, the g the lower one, so you get the total height of a text in the current font of the canvas.

Alluring

That's a hack after all ;) – Deviled

Maybe, but I have seen and used this quite often without any problems. In fact, I haven't found a satisfactory alternative, yet. I'd be very curious, though. I remember I've been having problems with either too small or too big values or poor performance, trying to solve this in another way. – Alluring

Oh, and LineSpacing in the sense of typography might include additional height units in order to set a multi-line text aestetically well. I'm not sure if there are cases, where LineSpacing in Wpf or similar behaves that way. If you really just want the actual text height without any possible additional space, this solution should be correct by definition, because it concentrates on the metrics of the glyphs the current font would produce. – Alluring