+ if (!control && !shift) return "";
+
+ newstate = control ? shift ? GRID_UNKNOWN : GRID_FULL : GRID_EMPTY;
+ if (state->grid[y * state->w + x] == newstate &&
+ state->grid[ui->cur_y * state->w + ui->cur_x] == newstate)
+ return "";
+
+ sprintf(buf, "%c%d,%d,%d,%d", control ? shift ? 'U' : 'F' : 'E',
+ min(x, ui->cur_x), min(y, ui->cur_y),
+ abs(x - ui->cur_x) + 1, abs(y - ui->cur_y) + 1);
+ return dupstr(buf);