fix: Support bold ANSI escape sequence

[gabe565]

The code to print bold text is currently commented out, even though it works fine. This PR uncomments it to add support for rendering bold text.

I also noticed that bold text wasn't very pronounced, so I changed the font-weight to bolder. If this is undesired, just let me know and I can remove that change.

Before:

After (with font-weight="bold"):

After (with font-weight="bolder"):

I also noticed the bold

Fixes #75

[meowgorithm]

Awesome, thanks for the PR. One question: why bolder instead of bold?

[gabe565]

@meowgorithm Maybe my machine is rendering fonts strangely, but bold doesn't look very different than regular text, so I was trying to make the effect more obvious. Would you prefer bold? That might make more sense

[meowgorithm]

@gabe565 can you render to PNG and post the results here? SVGs render differently depending on device (for example, the SVGs above look different on my phone versus my desktop).

bold is probably the better choice as the renderer will typically choose the actual bold typeface (i.e. JetBrains Mono Bold). bolder will look for the next weight heavier than regular (called medium), however because that font is typically not available, the renderer will synthesize a bolder version of the font, which is a bit of a typographic horror.

In other words, given than 400 (regular) is the default weight, bolder will look for the 500 weight which is typically not available, and synthesize a bold version of regular. If it is installed it likely won't be bold enough. bold, on the other hand, will always refer to 700.

Weight	Name	Filename
400	Regular	JetBrains-Mono-Regular.otf
500	Medium	Often not installed
600	Semibold	Often not installed
700	Bold	JetBrains-Mono-Bold.otf
800	Extra Bold	Often not installed
900	Black	Often not installed

[aymanbagabas]

Other than using "bold", looks good 🙂

[gabe565]

Thanks for the insight, I hadn't thought about rendering handled when a 500 weight font wasn't available. For some reason PNG rendering doesn't work on my machine, so let me try it in a container. I'm curious to see the difference

[gabe565]

Ok I went ahead and changed the weight back to bold since it sounds like that's the best solution. I tried generating PNGs, but the font weight looks exactly the same. I'm sure it isn't a testing issue because it still works when rendering to an SVG, so I'm not sure why the font weight looks the same.

I don't think it's super helpful, but here's what I get:

If I render to an SVG, the font-weight: bold is definitely there:

<tspan xml:space="preserve" font-weight="bold">Bold text</tspan>