+}
+
+static int
+make_box_index (int left_, int right_, int top_, int bottom_)
+{
+ bool rtl = render_direction_rtl ();
+ int left = ascii_line_from_render_line (rtl ? right_ : left_);
+ int right = ascii_line_from_render_line (rtl ? left_ : right_);
+ int top = ascii_line_from_render_line (top_);
+ int bottom = ascii_line_from_render_line (bottom_);
+
+ int idx = right;
+ idx = idx * ASCII_N_LINES + bottom;
+ idx = idx * ASCII_N_LINES + left;
+ idx = idx * ASCII_N_LINES + top;
+ return idx;