feat(性能优化): 提升速度

ofdgo_renderer.go

@@ -33,6 +33,7 @@ type Renderer struct {
 	FontMap               map[string]*canvas.FontFamily
 	FontGIDMap            map[string]map[uint16]rune
 	FontCIDMap            map[string]map[uint16]rune
+	fontFSCache           map[fontFSKey]*canvas.FontFamily
 	fontDirs              []string
 	fontFS                []fs.FS
 }