Guide lines

Drag from a ruler to create a horizontal or vertical guide line. (Drag it back into the ruler to delete it.) This is positioned in document space. *View* > *Guides* should go next to the existing *View* > *Rulers* menu to toggle their visibility. Snapping works with them like they're a line (just without endpoints, since guide lines are infinitely long). Like everything else that you can drag in Graphite, Esc and right-click cancel a drag, putting it back where it began (or deleting it if this was just brought into existence by dragging out of a ruler).

首先定位现有的标尺实现和 View > Rulers 菜单，然后跟踪在文档空间中如何处理拖动和吸附。如果存在相关的视图和交互测试，请检查它们。完成的标准是：可以从标尺创建和删除辅助线，可以通过 View > Guides 切换辅助线，可以参与吸附，并且可以使用 Esc 或右键单击正确取消。

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