Added color and font styles.

Sources/SwiftMathRender/MathRender/MTFont.swift

@@ -0,0 +1,78 @@
+//
+//  MTFont.swift
+//  MathRenderSwift
+//
+//  Created by Mike Griebling on 2022-12-31.
+//
+
+import Foundation
+import CoreGraphics
+import CoreText
+
+//
+//  Font.swift
+//  iosMath
+//
+//  Created by Kostub Deshmukh on 5/18/16.
+//
+//  This software may be modified and distributed under the terms of the
+//  MIT license. See the LICENSE file for details.
+//
+
+public class MTFont {
+    
+    var defaultCGFont: CGFont!
+    var ctFont: CTFont!
+    var mathTable: MTFontMathTable?
+    var rawMathTable: NSDictionary?
+    
+    init() {}
+    
+    convenience init(fontWithName name: String, size:CGFloat) {
+        // CTFontCreateWithName does not load the complete math font, it only has about half the glyphs of the full math font.
+        // In particular it does not have the math italic characters which breaks our variable rendering.
+        // So we first load a CGFont from the file and then convert it to a CTFont.
+        self.init()
+        print("Loading font %@", name);
+        let bundle = MTFont.fontBundle
+        let fontPath = bundle.path(forResource: name, ofType: "otf")
+        let fontDataProvider = CGDataProvider(filename: fontPath!)
+        self.defaultCGFont = CGFont(fontDataProvider!)!
+        print("Num glyphs: %zd", self.defaultCGFont.numberOfGlyphs)
+        
+        self.ctFont = CTFontCreateWithGraphicsFont(self.defaultCGFont, size, nil, nil);
+        
+        let mathTablePlist = bundle.url(forResource:name, withExtension:"plist")
+        let dict = NSDictionary(contentsOf: mathTablePlist!) // dictionaryWithContentsOfFile:mathTablePlist];
+        self.rawMathTable = dict
+        self.mathTable = MTFontMathTable(withFont:self, mathTable:rawMathTable!)
+    }
+    
+    static var fontBundle:Bundle {
+        // Uses bundle for class so that this can be access by the unit tests.
+        return Bundle(url: Bundle(for: self).url(forResource: "iosMathFonts", withExtension: "bundle")!)!
+    }
+    
+    func copy(withSize size: CGFloat) -> MTFont {
+        let newFont = MTFont()
+        newFont.defaultCGFont = self.defaultCGFont
+        newFont.ctFont = CTFontCreateWithGraphicsFont(self.defaultCGFont, size, nil, nil)
+        newFont.rawMathTable = self.rawMathTable
+        newFont.mathTable = MTFontMathTable(withFont: newFont, mathTable: newFont.rawMathTable!)
+        return newFont
+    }
+    
+    func get(nameForGlyph glyph:CGGlyph) -> String {
+        let name = self.defaultCGFont.name(for: glyph)
+        return name! as String
+    }
+    
+    func get(glyphWithName name:String) -> CGGlyph {
+        return self.defaultCGFont.getGlyphWithGlyphName(name: name as CFString)
+    }
+    
+    var fontSize:CGFloat {
+        return CTFontGetSize(self.ctFont)
+    }
+    
+}