FcWeightToOpenTypeDouble(3)

💅 FcWeightToOpenTypeDouble(3) — the fontconfig glow-up page

okay bestie, so this is a fontconfig manpage, section 3, and the star of the show is FcWeightToOpenTypeDouble. yes the name is a mouthful, no we are not renaming it, it's iconic and we respect it 🎀

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✨ NAME ✨

FcWeightToOpenTypeDouble — literally the function that converts fontconfig weight values into OpenType ones. that's the whole job. that's her main character arc 🦋

✨ SYNOPSIS ✨

#include <fontconfig/fontconfig.h>

double FcWeightToOpenTypeDouble (double ot_weight);

so you include the header (as always, #include <fontconfig/fontconfig.h>, no notes 📎) and then you call her with a double and she hands you back a double. double in, double out. symmetry. slay.

✨ DESCRIPTION ✨

okay so here's the tea ☕ — FcWeightToOpenTypeDouble is the inverse of FcWeightFromOpenType. they're giving complementary energies, yin and yang, the whole thing 💫

and now the important part, bestie, because this is the vibe check that can fail:

• if the input is less than FC_WEIGHT_THIN — too tiny, rejected 🙈
• or if the input is greater than FC_WEIGHT_EXTRABLACK — too much, also rejected 💀
• in either of those cases she returns -1. that's your "nope, out of range" signal, no cap.

otherwise? she returns a number in the range 1 to 1000. clean. gorgeous. a full range. 🔥

fr fr keep those bounds in mind — -1 is the "out of bounds" answer, not a real weight, so don't go treating it like one.

✨ SINCE ✨

available since version 2.12.92 ⭐ like she's been here, she's established, she's not new here 💅

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and that's the whole page, bestie — short, sweet, and extremely specific 🫶

this one's from Fontconfig 2.17.0, dated 27 June 2025, and it's the FcWeightToOpenTypeDouble(3) page — go convert some weights, ily, bye! 🎀🌸✨