1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
|
// +build darwin,!nucular_shiny nucular_gio
package font
import (
"crypto/md5"
"strings"
"sync"
"gioui.org/font/opentype"
"gioui.org/text"
"gioui.org/unit"
"golang.org/x/image/font"
"golang.org/x/image/math/fixed"
)
type Face struct {
fnt *opentype.Font
shaper *text.Cache
size int
fsize fixed.Int26_6
metrics font.Metrics
}
var fontsMu sync.Mutex
var fontsMap = map[[md5.Size]byte]*opentype.Font{}
func NewFace(ttf []byte, size int) (Face, error) {
key := md5.Sum(ttf)
fontsMu.Lock()
defer fontsMu.Unlock()
fnt, _ := fontsMap[key]
if fnt == nil {
var err error
fnt, err = opentype.Parse(ttf)
if err != nil {
return Face{}, err
}
}
shaper := text.NewCache([]text.FontFace{{text.Font{}, fnt}})
face := Face{fnt, shaper, size, fixed.I(size), font.Metrics{}}
metricsTxt, _ := face.shaper.Layout(text.Font{}, fixed.I(size), 1e6, strings.NewReader("metrics"))
face.metrics.Ascent = metricsTxt[0].Ascent
face.metrics.Descent = metricsTxt[0].Descent
face.metrics.Height = face.metrics.Ascent + face.metrics.Descent
return face, nil
}
func (face Face) Px(v unit.Value) int {
return face.size
}
func (face Face) Metrics() font.Metrics {
return face.metrics
}
|
