Basic sitemode

lib/terminal/cursor.dart

@@ -18,12 +18,20 @@ class Cursor {
     t._tiles = [for (var i = 0; i < nTiles; i += 1) Tile()];
   }
 
-  void putc(int c) {
+  void putc(int? c) {
     for (var dx = 0; dx < font.cellWidth; dx += 1) {
       for (var dy = 0; dy < font.cellHeight; dy += 1) {
         var i = t._fromXY(x + dx, y + dy);
 
         if (i != null) {
+          // you can pass null and in that case a character-sized block of
+          // screen is automatically UI-affected, but not drawn
+          if (c == null) {
+            t._tiles[i].highlightGroup = highlightGroup;
+            t._tiles[i].actions.addAll(_acts);
+            continue;
+          }
+
           final (sourceCx, sourceCy) = (
             (c % font.nCellsW) * font.cellWidth + dx,
             (c ~/ font.nCellsW) * font.cellHeight + dy
@@ -48,6 +56,13 @@ class Cursor {
     }
   }
 
+  void touch(int n) {
+    for (var i = 0; i < n; i++) {
+      putc(null);
+      x += font.cellWidth;
+    }
+  }
+
   void puts(String s) {
     var startX = x;
     for (final c in toCp437String(s)) {