Add pixel font, wrapping and micro font

pixel/micro.go

@@ -0,0 +1,104 @@
+package pixel
+
+import (
+	"fmt"
+	"strings"
+	"unicode"
+)
+
+const (
+	MicroAdvance = 4
+	MicroHeight  = 5
+)
+
+// Hand-placed 3×5 glyphs; rows split by |.
+var micro = microFont(map[rune]string{
+	' ': "...|...|...|...|...",
+	'0': "###|#.#|#.#|#.#|###",
+	'1': ".#.|##.|.#.|.#.|###",
+	'2': "###|..#|###|#..|###",
+	'3': "###|..#|.##|..#|###",
+	'4': "#.#|#.#|###|..#|..#",
+	'5': "###|#..|###|..#|###",
+	'6': "###|#..|###|#.#|###",
+	'7': "###|..#|.#.|.#.|.#.",
+	'8': "###|#.#|###|#.#|###",
+	'9': "###|#.#|###|..#|###",
+	'A': ".#.|#.#|###|#.#|#.#",
+	'B': "##.|#.#|##.|#.#|##.",
+	'C': ".##|#..|#..|#..|.##",
+	'D': "##.|#.#|#.#|#.#|##.",
+	'E': "###|#..|##.|#..|###",
+	'F': "###|#..|##.|#..|#..",
+	'G': ".##|#..|#.#|#.#|.##",
+	'H': "#.#|#.#|###|#.#|#.#",
+	'I': "###|.#.|.#.|.#.|###",
+	'J': "..#|..#|..#|#.#|.#.",
+	'K': "#.#|#.#|##.|#.#|#.#",
+	'L': "#..|#..|#..|#..|###",
+	'M': "#.#|###|###|#.#|#.#",
+	'N': "##.|#.#|#.#|#.#|#.#",
+	'O': ".#.|#.#|#.#|#.#|.#.",
+	'P': "##.|#.#|##.|#..|#..",
+	'Q': ".#.|#.#|#.#|##.|.##",
+	'R': "##.|#.#|##.|#.#|#.#",
+	'S': ".##|#..|.#.|..#|##.",
+	'T': "###|.#.|.#.|.#.|.#.",
+	'U': "#.#|#.#|#.#|#.#|###",
+	'V': "#.#|#.#|#.#|#.#|.#.",
+	'W': "#.#|#.#|###|###|#.#",
+	'X': "#.#|#.#|.#.|#.#|#.#",
+	'Y': "#.#|#.#|.#.|.#.|.#.",
+	'Z': "###|..#|.#.|#..|###",
+	'+': "...|.#.|###|.#.|...",
+	'-': "...|...|###|...|...",
+	'.': "...|...|...|...|.#.",
+	':': "...|.#.|...|.#.|...",
+	'/': "..#|..#|.#.|#..|#..",
+	'%': "#.#|..#|.#.|#..|#.#",
+	'!': ".#.|.#.|.#.|...|.#.",
+})
+
+func microFont(art map[rune]string) map[rune][MicroHeight]uint8 {
+	out := map[rune][MicroHeight]uint8{}
+	for r, a := range art {
+		rows := strings.Split(a, "|")
+		if len(rows) != MicroHeight {
+			panic(fmt.Sprintf("pixel: micro %q needs %d rows", r, MicroHeight))
+		}
+		var g [MicroHeight]uint8
+		for y, row := range rows {
+			if len(row) != 3 || strings.Trim(row, ".#") != "" {
+				panic(fmt.Sprintf("pixel: micro %q row %q", r, row))
+			}
+			for x := range 3 {
+				if row[x] == '#' {
+					g[y] |= 4 >> x
+				}
+			}
+		}
+		out[r] = g
+	}
+	return out
+}
+
+func microGlyph(r rune) [MicroHeight]uint8 {
+	g, ok := micro[unicode.ToUpper(r)]
+	if !ok {
+		panic(fmt.Sprintf("pixel: micro font lacks %q", r))
+	}
+	return g
+}
+
+// MicroWidth returns the width of s in dots.
+func MicroWidth(s string) int {
+	n := 0
+	for _, r := range s {
+		microGlyph(r)
+		n++
+	}
+	if n == 0 {
+		return 0
+	}
+	return n*MicroAdvance - 1
+}