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package widget
import (
"fmt"
"sync"
"image"
"image/draw"
"volute/gui"
"volute/gui/text"
"volute/gui/win"
)
func Output(val <-chan float64, r image.Rectangle, env gui.Env, wg *sync.WaitGroup) {
defer wg.Done()
defer close(env.Draw())
var v float64 = 0.0
env.Draw() <- outputDraw(v, r)
Loop:
for {
select {
case v = <-val:
env.Draw() <- outputDraw(v, r)
case event, ok := <-env.Events():
if !ok { // channel closed
break Loop
}
if event, ok := event.(win.WiFocus); ok && event.Focused {
env.Draw() <- outputDraw(v, r)
}
}
}
}
func outputDraw(v float64, r image.Rectangle) func(draw.Image) image.Rectangle {
return func(drw draw.Image) image.Rectangle {
text.Draw([]byte(fmt.Sprintf("%.3f", v)), drw, r, BLACK, WHITE)
return r
}
}
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