ui: shorten OpReader.Decode for loops

Signed-off-by: Elias Naur <mail@eliasnaur.com>

ui/app/internal/gpu/gpu.go

@@ -659,11 +659,7 @@ func (d *drawOps) collectOps(r *ui.OpsReader, state drawState) int {
 	var aux []byte
 	var auxKey ui.OpKey
 loop:
-	for {
+	for encOp, ok := r.Decode(); ok; encOp, ok = r.Decode() {
-		encOp, ok := r.Decode()
-		if !ok {
-			break
-		}
 		switch ops.OpType(encOp.Data[0]) {
 		case ops.TypeTransform:
 			var op ui.TransformOp

ui/app/window.go

@@ -158,11 +158,7 @@ func (w *Window) Draw(root *ui.Ops) {
 func collectRedraws(r *ui.OpsReader) (time.Time, bool) {
 	var t time.Time
 	redraw := false
-	for {
+	for encOp, ok := r.Decode(); ok; encOp, ok = r.Decode() {
-		encOp, ok := r.Decode()
-		if !ok {
-			break
-		}
 		switch ops.OpType(encOp.Data[0]) {
 		case ops.TypeInvalidate:
 			var op ui.InvalidateOp

ui/input/key.go

@@ -88,11 +88,7 @@ func (q *keyQueue) resolveFocus(events handlerEvents) (Key, listenerPriority, bo
 	var pri listenerPriority
 	var hide bool
 loop:
-	for {
+	for encOp, ok := q.reader.Decode(); ok; encOp, ok = q.reader.Decode() {
-		encOp, ok := q.reader.Decode()
-		if !ok {
-			break
-		}
 		switch ops.OpType(encOp.Data[0]) {
 		case ops.TypeKeyHandler:
 			var op key.HandlerOp

ui/input/pointer.go

@@ -63,11 +63,7 @@ const (
 )
 
 func (q *pointerQueue) collectHandlers(r *ui.OpsReader, events handlerEvents, t ui.Transform, area, node int, pass bool) {
-	for {
+	for encOp, ok := r.Decode(); ok; encOp, ok = r.Decode() {
-		encOp, ok := r.Decode()
-		if !ok {
-			return
-		}
 		switch ops.OpType(encOp.Data[0]) {
 		case ops.TypePush:
 			q.collectHandlers(r, events, t, area, node, pass)