Added a fvar table test. This might be a bit more complicated...

doc/export/fvar.swift

@@ -0,0 +1,61 @@
+// 2 november 2017
+import Cocoa
+import CoreText
+
+func fourccString(_ k: FourCharCode) -> String {
+	var c: [UInt8] = [0, 0, 0, 0]
+	c[0] = UInt8((k >> 24) & 0xFF)
+	c[1] = UInt8((k >> 16) & 0xFF)
+	c[2] = UInt8((k >> 8) & 0xFF)
+	c[3] = UInt8(k & 0xFF)
+	return String(bytes: c, encoding: .utf8)!
+}
+
+var weightMin: Double = 0
+var weightMax: Double = 0
+var weightDef: Double = 0
+var weightVals: [String: Double] = [:]
+
+let attrs: [String: String] = [
+	kCTFontFamilyNameAttribute as String:		"Skia",
+]
+let bd = CTFontDescriptorCreateWithAttributes(attrs as CFDictionary)
+let matches = CTFontDescriptorCreateMatchingFontDescriptors(bd, nil) as! [CTFontDescriptor]
+let mfont = CTFontCreateWithFontDescriptor(matches[0], 0.0, nil)
+let master = CTFontCopyVariationAxes(mfont) as! [NSDictionary]
+master.forEach { d in
+	print("axis {")
+	d.forEach { k, v in
+		if (k as! String) == (kCTFontVariationAxisIdentifierKey as String) {
+			let c = v as! FourCharCode
+			print("\t\(k) \(fourccString(c))")
+		} else {
+			print("\t\(k) \(v)")
+		}
+	}
+	print("}")
+	if (d[kCTFontVariationAxisNameKey] as! String) == "Weight" {
+		weightMin = d[kCTFontVariationAxisMinimumValueKey] as! Double
+		weightMax = d[kCTFontVariationAxisMaximumValueKey] as! Double
+		weightDef = d[kCTFontVariationAxisDefaultValueKey] as! Double
+	}
+}
+print("")
+matches.forEach { d in
+	let f = CTFontDescriptorCopyAttribute(d, kCTFontVariationAttribute) as! [FourCharCode: Double]
+	let n = CTFontDescriptorCopyAttribute(d, kCTFontStyleNameAttribute) as! String
+	print("\(n) {")
+	f.forEach { k, v in
+		print("\t\(fourccString(k)) \(v)")
+	}
+	print("}")
+	weightVals[n] = weightDef
+	if let v = f[2003265652] {
+		weightVals[n] = v
+	}
+}
+print("")
+weightVals.forEach { k, v in
+	let scaled = (v - weightMin) / (weightMax - weightMin)
+	print("\(k) scaled = \(scaled) (OS2 \(UInt16(scaled * 1000)))")
+}