func (self *face) Glyph(dot fixed.Point26_6, char rune) (dr image.Rectangle, mask image.Image, maskp image.Point, advance fixed.Int26_6, ok bool) {
var bounds fixed.Rectangle26_6
var cached bool
var cachedGlyph glyph
if cachedGlyph, cached = self.cache.get(char); cached {
bounds, advance, mask = cachedGlyph.bounds, cachedGlyph.advance, cachedGlyph.mask
}
if bounds == (fixed.Rectangle26_6{}) || advance == 0 {
if bounds, advance, ok = self.GlyphBounds(char); !ok {
return
}
}
offset := fixed.Point26_6{
X: abs26_6(bounds.Min.X),
Y: self.metrics.Ascent,
}
origin := C.CGPoint{
x: C.CGFloat(f64(offset.X)),
y: C.CGFloat(f64(offset.Y)),
}
dx := (int(bounds.Max.X+offset.X) >> 6) + 1
dy := (int(self.metrics.Ascent+self.metrics.Descent) >> 6) + 1
dr.Min.X = (int(dot.X) >> 6) - int(origin.x)
dr.Min.Y = (int(dot.Y) >> 6) - int(origin.y)
dr.Max.X = dr.Min.X + dx
dr.Max.Y = dr.Min.Y + dy
if mask == nil {
alpha := image.NewAlpha(image.Rect(0, 0, dx, dy))
if !C.CTFontGlyphDraw__(
self.ref,
C.UTF32Char(char),
origin,
(*C.UInt8)(unsafe.Pointer(&alpha.Pix[0])),
C.size_t(alpha.Stride),
C.size_t(dx),
C.size_t(dy),
) {
dr, advance = image.Rectangle{}, 0
return
}
mask = alpha
self.cache.set(glyph{rune: char, bounds: bounds, advance: advance, mask: mask})
}
ok = true
return
}
func (self *face) GlyphAdvance(char rune) (advance fixed.Int26_6, ok bool) {
if cachedGlyph, cached := self.cache.get(char); cached {
advance, ok = cachedGlyph.advance, true
return
}
if a := C.CTFontGlyphAdvance__(self.ref, C.UTF32Char(char)); a != 0 {
advance, ok = i26_6(a), true
self.cache.set(glyph{rune: char, advance: advance})
}
return
}
func (self *face) GlyphBounds(char rune) (bounds fixed.Rectangle26_6, advance fixed.Int26_6, ok bool) {
if cachedGlyph, cached := self.cache.get(char); cached {
if cachedGlyph.bounds != (fixed.Rectangle26_6{}) {
bounds, advance, ok = cachedGlyph.bounds, cachedGlyph.advance, true
return
}
}
r := C.CGRect{}
a := C.CTFontGlyphBounds__(self.ref, C.UTF32Char(char), &r)
if a != 0 {
bounds, advance, ok = r26_6(r), i26_6(a), true
self.cache.set(glyph{rune: char, bounds: bounds, advance: advance})
}
return
}
func (self *face) Kern(char0 rune, char1 rune) fixed.Int26_6 {
k := C.CTFontKern__(self.ref, C.UTF32Char(char0), C.UTF32Char(char1))
return i26_6(k)
}
