Substitute unknown glyphs

internal/ui/noninteractive.go

@@ -320,14 +320,20 @@ func (l *label) regions(tick int) []region {
 	pt := l.pos()
 
 	for _, r := range l.str {
-		glyph, err := l.font.Glyph(r)
-		if err != nil {
-			log.Printf("FIXME: ignoring misssing glyph %v", r)
+		var sprite *assetstore.Sprite
+		if glyph, err := l.font.Glyph(r); err != nil {
+			if glyph, err := l.font.Glyph('?'); err != nil {
+				log.Printf("FIXME: ignoring glyph %v", r)
 				continue
+			} else {
+				sprite = glyph
+			}
+		} else {
+			sprite = glyph
 		}
 
-		out = append(out, oneRegion(pt, glyph.Image)...)
-		pt.X += glyph.Rect.Dx()
+		out = append(out, oneRegion(pt, sprite.Image)...)
+		pt.X += sprite.Rect.Dx()
 	}
 
 	return out