Start work on emoji (mostly to be scrapped tho)

.gitignore

@@ -0,0 +1,2 @@
+noto_emojis
+example/emojis/out.png

emoji.go

@@ -0,0 +1,76 @@
+package freetype
+
+import (
+	"errors"
+	"fmt"
+	"strings"
+	"unicode/utf8"
+)
+
+type Emoji struct {
+	Codepoints []rune
+	Bytes      int
+}
+
+var (
+	errNotAnEmoji = errors.New("not an emoji")
+)
+
+func inrange(val, min, max rune) bool {
+	return val >= min && val < max
+}
+
+// https://stackoverflow.com/questions/30757193/find-out-if-character-in-string-is-emoji/39425959
+func isEmoji(chr rune) bool {
+	switch {
+	case inrange(chr, 0x1f600, 0x1f64f), // Emoticons
+		inrange(chr, 0x1f300, 0x1f5ff), // Misc Symbols and Pictographs
+		inrange(chr, 0x1f680, 0x1f6ff), // Transport and Map
+		inrange(chr, 0x1f1e6, 0x1f1ff), // Regional country flags
+		inrange(chr, 0x2600, 0x26ff),   // Misc symbols
+		inrange(chr, 0x2700, 0x27bf),   // Dingbats
+		inrange(chr, 0xfe00, 0xfe0f),   // Variation Selectors
+		inrange(chr, 0x1f900, 0x1f9ff), // Supplemental Symbols and Pictographs
+		inrange(chr, 127000, 127600),   // Various asian characters
+		inrange(chr, 65024, 65039),     // Variation selector
+		inrange(chr, 9100, 9300),       // Misc items
+		inrange(chr, 8400, 8447):       // Combining Diacritical Marks for Symbols
+		return true
+	}
+	return false
+}
+
+func isZWJ(chr rune) bool {
+	return chr == 8205
+}
+
+func parseEmoji(str string) (Emoji, error) {
+	if len(str) < 1 {
+		return Emoji{}, errNotAnEmoji
+	}
+
+	emoji := Emoji{}
+
+	for _, r := range str {
+		// Check if rune is emoji
+		if !isEmoji(r) && !isZWJ(r) {
+			if len(emoji.Codepoints) < 1 {
+				return emoji, errNotAnEmoji
+			}
+			break
+		}
+
+		emoji.Codepoints = append(emoji.Codepoints, r)
+		emoji.Bytes += utf8.RuneLen(r)
+	}
+
+	return emoji, nil
+}
+
+func (e Emoji) String() string {
+	codepoints := []string{}
+	for _, cp := range e.Codepoints {
+		codepoints = append(codepoints, fmt.Sprintf("%U", cp))
+	}
+	return "Emoji(" + strings.Join(codepoints, ", ") + ")"
+}

example/emojis/main.go

@@ -0,0 +1,124 @@
+// Copyright 2010 The Freetype-Go Authors. All rights reserved.
+// Use of this source code is governed by your choice of either the
+// FreeType License or the GNU General Public License version 2 (or
+// any later version), both of which can be found in the LICENSE file.
+
+// +build example
+//
+// This build tag means that "go install github.com/golang/freetype/..."
+// doesn't install this example program. Use "go run main.go" to run it or "go
+// install -tags=example" to install it.
+
+package main
+
+import (
+	"bufio"
+	"flag"
+	"fmt"
+	"image"
+	"image/color"
+	"image/draw"
+	"image/png"
+	"io/ioutil"
+	"log"
+	"os"
+
+	"git.fromouter.space/crunchy-rocks/freetype"
+	"golang.org/x/image/font"
+)
+
+var (
+	dpi      = flag.Float64("dpi", 72, "screen resolution in Dots Per Inch")
+	fontfile = flag.String("fontfile", "../../testdata/luxisr.ttf", "filename of the ttf font")
+	hinting  = flag.String("hinting", "none", "none | full")
+	size     = flag.Float64("size", 20, "font size in points")
+	spacing  = flag.Float64("spacing", 1.5, "line spacing (e.g. 2 means double spaced)")
+	wonb     = flag.Bool("whiteonblack", false, "white text on a black background")
+)
+
+var text = []string{
+	"Single glyph emoji: 😂",
+	"Gender-modified emoji: 💂‍♀️",
+	"Skin-modified emoji: 🖐🏽",
+	"Mixed emoji: 👩‍👩‍👧‍👧",
+	"👌👀👌👀👌👀👌👀👌👀 good shit go౦ԁ sHit👌 thats ✔ some good👌👌shit right👌👌",
+	"th 👌 ere👌👌👌 right✔there ✔✔if i do ƽaү so my selｆ 💯 i say so ",
+	"💯 thats what im talking about right there right there (chorus: ʳᶦᵍʰᵗ ᵗʰᵉʳᵉ)",
+	"mMMMMᎷМ💯 👌👌 👌НO0ОଠＯOOＯOОଠଠOoooᵒᵒᵒᵒᵒᵒᵒᵒᵒ👌 👌👌 👌 💯 👌 👀 👀 👀 👌👌Good shit",
+}
+
+func main() {
+	flag.Parse()
+
+	// Read the font data.
+	fontBytes, err := ioutil.ReadFile(*fontfile)
+	if err != nil {
+		log.Println(err)
+		return
+	}
+	f, err := freetype.ParseFont(fontBytes)
+	if err != nil {
+		log.Println(err)
+		return
+	}
+
+	// Initialize the context.
+	fg, bg := image.Black, image.White
+	ruler := color.RGBA{0xdd, 0xdd, 0xdd, 0xff}
+	if *wonb {
+		fg, bg = image.White, image.Black
+		ruler = color.RGBA{0x22, 0x22, 0x22, 0xff}
+	}
+	rgba := image.NewRGBA(image.Rect(0, 0, 640, 480))
+	draw.Draw(rgba, rgba.Bounds(), bg, image.ZP, draw.Src)
+	c := freetype.NewContext()
+	c.SetDPI(*dpi)
+	c.SetFont(f)
+	c.SetFontSize(*size)
+	c.SetClip(rgba.Bounds())
+	c.SetDst(rgba)
+	c.SetSrc(fg)
+	switch *hinting {
+	default:
+		c.SetHinting(font.HintingNone)
+	case "full":
+		c.SetHinting(font.HintingFull)
+	}
+
+	// Draw the guidelines.
+	for i := 0; i < 200; i++ {
+		rgba.Set(10, 10+i, ruler)
+		rgba.Set(10+i, 10, ruler)
+	}
+
+	// Draw the text.
+	pt := freetype.Pt(10, 10+int(c.PointToFixed(*size)>>6))
+	for _, s := range text {
+		_, err = c.DrawString(s, pt)
+		if err != nil {
+			log.Println(err)
+			return
+		}
+		pt.Y += c.PointToFixed(*size * *spacing)
+	}
+
+	// Save that RGBA image to disk.
+	outFile, err := os.Create("out.png")
+	if err != nil {
+		log.Println(err)
+		os.Exit(1)
+	}
+	defer outFile.Close()
+	b := bufio.NewWriter(outFile)
+	err = png.Encode(b, rgba)
+	if err != nil {
+		log.Println(err)
+		os.Exit(1)
+	}
+	err = b.Flush()
+	if err != nil {
+		log.Println(err)
+		os.Exit(1)
+	}
+	fmt.Println("Wrote out.png OK.")
+}

freetype.go

@@ -10,6 +10,7 @@ package freetype // import "git.fromouter.space/crunchy-rocks/freetype"
 
 import (
 	"errors"
+	"fmt"
 	"image"
 	"image/draw"
 
@@ -232,8 +233,21 @@ func (c *Context) DrawString(s string, p fixed.Point26_6) (fixed.Point26_6, erro
 		return fixed.Point26_6{}, errors.New("freetype: DrawText called with a nil font")
 	}
 	prev, hasPrev := truetype.Index(0), false
-	for _, rune := range s {
-		index := c.f.Index(rune)
+	nextchar := 0
+	for index, r := range s {
+		// Check if we need to skip entries
+		if nextchar > index {
+			continue
+		}
+		// Check if rune is an emoji
+		if isEmoji(r) {
+			emoji, err := parseEmoji(s[index:])
+			if err == nil {
+				fmt.Println("Found emoji:", emoji)
+				nextchar = index + emoji.Bytes
+			}
+		}
+		index := c.f.Index(r)
 		if hasPrev {
 			kern := c.f.Kern(c.scale, prev, index)
 			if c.hinting != font.HintingNone {