diff options
| -rw-r--r-- | src/Fl_Tree_Item.cxx | 33 |
1 files changed, 28 insertions, 5 deletions
diff --git a/src/Fl_Tree_Item.cxx b/src/Fl_Tree_Item.cxx index c8f3d0e00..616a77392 100644 --- a/src/Fl_Tree_Item.cxx +++ b/src/Fl_Tree_Item.cxx @@ -1144,11 +1144,34 @@ void Fl_Tree_Item::draw(int X, int &Y, int W, Fl_Tree_Item *itemfocus, Y += prefs.openchild_marginbottom(); // offset below open child tree } if ( ! lastchild ) { - // Special 'clipped' calculation. (intentional variable shadowing) - int is_clipped = ((child_y_start < tree_top) && (Y < tree_top)) || - ((child_y_start > tree_bot) && (Y > tree_bot)); - if (render && !is_clipped ) - draw_vertical_connector(hconn_x, child_y_start, Y, prefs); + // Draw vertical connector between this item and the bottom of its children. + // + // o Aaa <- Item we're drawing has >20k children. + // ytop → : :.. 0001 + // : :.. 0002 + // : : } ~20k items + // : :.. 19998 + // ┌──:──:.. 19999 ──┐ + // │ : :.. 20000 │ + // │ : :.. 20001 │ <- visible screen + // │ : :.. 20002 │ area + // └──:──:.. 20003 ──┘ + // : :.. 20004 + // : + // ybot → : ← we're drawing this long vertical connector + // : + // o Bbb + // + int ytop = child_y_start; + int ybot = Y; + int is_clipped = ((ytop < tree_top) && (ybot < tree_top)) || // completely off top of scrn? clip + ((ytop > tree_bot) && (ybot > tree_bot)); // completely off bot of scrn? clip + if (render && !is_clipped ) { + // Clip vert line to within screen area + ytop = (ytop < tree_top) ? tree_top : ytop; + ybot = (ybot > tree_bot) ? tree_bot : ybot; + draw_vertical_connector(hconn_x, ytop, ybot, prefs); + } } } } |