// XXX: Currently only usable on main screen. Unbuffered needs some love later.
func ScrollWriteUpwards(panel *panel.Buffered, s string) {
lines := strings.Split(s, "\n")
buf := panel.Buffer()
r := panel.Bounds()
var (
length = r.Dx() * len(lines)
START = 0
STARTLINES = START + length
END = len(buf)
ENDLINES = END - length
)
src := buf[STARTLINES:]
target := buf[:ENDLINES]
width := r.Dx()
for i := 0; i < len(target); i += width {
copy(target[i:i+width], src[i:i+width])
}
for i := 0; i < len(lines); i++ {
clearRow(panel, r.Dy()-1-i)
}
targetr := panel.Area(image.Rect(0, r.Dy()-len(lines), width, r.Dy()))
targetr.Write([]byte(s))
}
func ScrollWrite(panel *panel.Buffered, s string) {
lines := strings.Split(s, "\n")
buf := panel.Buffer()
r := panel.Bounds()
var (
length = r.Dx() * len(lines)
START = 0
STARTLINES = START + length
END = len(buf)
ENDLINES = END - length
)
src := buf[:ENDLINES]
target := buf[STARTLINES:]
width := r.Dx()
for i := len(target) - width; i >= 0; i -= width {
copy(target[i:i+width], src[i:i+width])
}
for i := 0; i < len(lines); i++ {
clearRow(panel, i)
}
panel.Write([]byte(s))
}
func clearRow(panel *panel.Buffered, row int) {
// TODO: Possibly change to copying []Cell{' ', 0, 0...} instead, speed vs allocating more memory.
// Consider using unexported big enough []Cell ready just for fast wiping.
r := panel.Bounds()
if row < 0 || row >= r.Dy() {
return
}
buf := panel.Buffer()
for i := row * r.Dx(); i < row*r.Dx()+r.Dx(); i++ {
buf[i] = termbox.Cell{' ', 0, 0}
}
}