restructure Text writing for more flexibility and consistency

This commit is contained in:
faiface 2017-05-07 20:59:56 +02:00
parent 5b524dadd8
commit c9eea2639e
1 changed files with 60 additions and 80 deletions

View File

@ -43,6 +43,7 @@ type Text struct {
lineHeight float64
tabWidth float64
buf []byte
prevR rune
bounds pixel.Rect
glyph pixel.TrianglesData
@ -131,106 +132,85 @@ func (txt *Text) Clear() {
}
func (txt *Text) Write(p []byte) (n int, err error) {
n, err = len(p), nil // always returns this
if len(p) == 0 {
return
}
for len(p) > 0 {
r, size := utf8.DecodeRune(p)
p = p[size:]
txt.WriteRune(r)
}
return
txt.buf = append(txt.buf, p...)
txt.drawBuf()
return len(p), nil
}
func (txt *Text) WriteString(s string) (n int, err error) {
if len(s) == 0 {
return
}
for _, r := range s {
txt.WriteRune(r)
}
txt.buf = append(txt.buf, s...)
txt.drawBuf()
return len(s), nil
}
func (txt *Text) WriteByte(c byte) error {
//FIXME: this is not correct, what if I want to write a 4-byte rune byte by byte?
_, err := txt.WriteRune(rune(c))
return err
txt.buf = append(txt.buf, c)
txt.drawBuf()
return nil
}
func (txt *Text) WriteRune(r rune) (n int, err error) {
n, err = utf8.RuneLen(r), nil // always returns this
var b [4]byte
n = utf8.EncodeRune(b[:], r)
txt.buf = append(txt.buf, b[:n]...)
txt.drawBuf()
return n, nil
}
switch r {
case '\n':
txt.Dot -= pixel.Y(txt.lineHeight)
txt.Dot = txt.Dot.WithX(txt.Orig.X())
return
case '\r':
txt.Dot = txt.Dot.WithX(txt.Orig.X())
return
case '\t':
rem := math.Mod(txt.Dot.X()-txt.Orig.X(), txt.tabWidth)
rem = math.Mod(rem, rem+txt.tabWidth)
if rem == 0 {
rem = txt.tabWidth
func (txt *Text) drawBuf() {
for utf8.FullRune(txt.buf) {
r, size := utf8.DecodeRune(txt.buf)
txt.buf = txt.buf[size:]
switch r {
case '\n':
txt.Dot -= pixel.Y(txt.lineHeight)
txt.Dot = txt.Dot.WithX(txt.Orig.X())
continue
case '\r':
txt.Dot = txt.Dot.WithX(txt.Orig.X())
continue
case '\t':
rem := math.Mod(txt.Dot.X()-txt.Orig.X(), txt.tabWidth)
rem = math.Mod(rem, rem+txt.tabWidth)
if rem == 0 {
rem = txt.tabWidth
}
txt.Dot += pixel.X(rem)
continue
}
txt.Dot += pixel.X(rem)
return
}
if !txt.atlas.Contains(r) {
r = unicode.ReplacementChar
}
if !txt.atlas.Contains(unicode.ReplacementChar) {
return
}
var rect, frame, bounds pixel.Rect
rect, frame, bounds, txt.Dot = txt.Atlas().DrawRune(txt.prevR, r, txt.Dot)
glyph := txt.atlas.Glyph(r)
txt.prevR = r
if txt.prevR >= 0 {
txt.Dot += pixel.X(txt.atlas.Kern(txt.prevR, r))
}
rv := [...]pixel.Vec{pixel.V(rect.Min.X(), rect.Min.Y()),
pixel.V(rect.Max.X(), rect.Min.Y()),
pixel.V(rect.Max.X(), rect.Max.Y()),
pixel.V(rect.Min.X(), rect.Max.Y()),
}
fv := [...]pixel.Vec{pixel.V(frame.Min.X(), frame.Min.Y()),
pixel.V(frame.Max.X(), frame.Min.Y()),
pixel.V(frame.Max.X(), frame.Max.Y()),
pixel.V(frame.Min.X(), frame.Max.Y()),
}
for i, j := range [...]int{0, 1, 2, 0, 2, 3} {
txt.glyph[i].Position = rv[j]
txt.glyph[i].Picture = fv[j]
}
txt.tris = append(txt.tris, txt.glyph...)
txt.dirty = true
glyphBounds := glyph.Frame.Moved(txt.Dot - glyph.Orig)
if glyphBounds.W()*glyphBounds.H() != 0 {
glyphBounds = pixel.R(
glyphBounds.Min.X(),
txt.Dot.Y()-txt.Atlas().Descent(),
glyphBounds.Max.X(),
txt.Dot.Y()+txt.Atlas().Ascent(),
)
if txt.bounds.W()*txt.bounds.H() == 0 {
txt.bounds = glyphBounds
txt.bounds = bounds
} else {
txt.bounds = txt.bounds.Union(glyphBounds)
txt.bounds = txt.bounds.Union(bounds)
}
}
a := pixel.V(glyph.Frame.Min.X(), glyph.Frame.Min.Y())
b := pixel.V(glyph.Frame.Max.X(), glyph.Frame.Min.Y())
c := pixel.V(glyph.Frame.Max.X(), glyph.Frame.Max.Y())
d := pixel.V(glyph.Frame.Min.X(), glyph.Frame.Max.Y())
for i, v := range []pixel.Vec{a, b, c, a, c, d} {
txt.glyph[i].Position = v - glyph.Orig + txt.Dot
txt.glyph[i].Picture = v
}
txt.tris = append(txt.tris, txt.glyph...)
txt.Dot += pixel.X(glyph.Advance)
txt.prevR = r
txt.dirty = true
return
}
func (txt *Text) Draw(t pixel.Target) {