small changes

gui.go

@@ -75,8 +75,6 @@ type GuiMutexes struct {
 	tickingMutex sync.Mutex
 
 	ViewsMutex sync.Mutex
-
-	drawMutex sync.Mutex
 }
 
 type PlayMode int
@@ -936,8 +934,6 @@ func (g *Gui) drawListFooter(v *View, fgColor, bgColor Attribute) error {
 
 // flush updates the gui, re-drawing frames and buffers.
 func (g *Gui) flush() error {
-	g.Mutexes.drawMutex.Lock()
-	defer g.Mutexes.drawMutex.Unlock()
 
 	// pretty sure we don't need this, but keeping it here in case we get weird visual artifacts
 	// g.clear(g.FgColor, g.BgColor)
@@ -966,18 +962,6 @@ func (g *Gui) flush() error {
 	return nil
 }
 
-func (g *Gui) Draw(v *View) error {
-	g.Mutexes.drawMutex.Lock()
-	defer g.Mutexes.drawMutex.Unlock()
-
-	if err := g.draw(v); err != nil {
-		return err
-	}
-
-	Screen.Show()
-	return nil
-}
-
 // draw manages the cursor and calls the draw function of a view.
 func (g *Gui) draw(v *View) error {
 	if g.suspended {

view.go

@@ -879,11 +879,18 @@ func (v *View) draw() error {
 	if v.Autoscroll && visibleViewLinesHeight > maxY {
 		v.oy = visibleViewLinesHeight - maxY
 	}
-	y := 0
+
-	for i, vline := range v.viewLines {
+	if len(v.viewLines) == 0 {
-		if i < v.oy {
+		return nil
-			continue
 	}
+
+	start := v.oy
+	if start > len(v.viewLines)-1 {
+		start = len(v.viewLines) - 1
+	}
+
+	y := 0
+	for _, vline := range v.viewLines[start:] {
 		if y >= maxY {
 			break
 		}
@@ -1112,14 +1119,6 @@ func (v *View) SetHighlight(y int, on bool) error {
 	return nil
 }
 
-func lineWidth(line []cell) (n int) {
-	for i := range line {
-		n += runewidth.RuneWidth(line[i].chr)
-	}
-
-	return
-}
-
 func lineWrap(line []cell, columns int) [][]cell {
 	if columns == 0 {
 		return [][]cell{line}
@@ -1227,3 +1226,16 @@ func (v *View) ClearTextArea() {
 	_ = v.SetOrigin(0, 0)
 	_ = v.SetCursor(0, 0)
 }
+
+// only call this function if you don't care where v.wx and v.wy end up
+func (v *View) OverwriteLines(y int, content string) {
+	v.writeMutex.Lock()
+	defer v.writeMutex.Unlock()
+
+	// break by newline, then for each line, write it, then add that erase command
+	v.wx = 0
+	v.wy = y
+
+	lines := strings.Replace(content, "\n", "\x1b[K\n", -1)
+	v.writeString(lines)
+}