底图约束

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Revision as of 01:11, 5 June 2019 by Wconly (talk | contribs) (Created page with "== 水平约束与垂直约束 ==")

描述

底图工作台工具中,您可以通过指针单击3D视图来拾取图形中的点、距离、半径与角度。

但是,当这些参数需要特别精准时,可能就要在工具对话框中输入准确的底图坐标

选择更加精准点的另一种方式是:在X、Y或Z的某一特定方向上对指针的移动加以约束。

水平约束与垂直约束

Perpendicular lines that were created by constraining the position of the points orthogonally

Hold the Shift key while drawing to force the next point to be constrained horizontally (X direction) or vertically (Y direction) in relation to the last point entered. The horizontal or vertical orientation depends on the position of the pointer when you press Shift; if you are more east or west from the last point, it will be horizontal; if you are more north or south, it will be vertical. To change the orientation, just release Shift, move the pointer to a new location, and hold Shift again.

Some tools like Draft Offset and Draft Trimex use constraining differently. They do not constrain vertically or horizontally but use a different method more adapted to the particular tool, for example, constraining the operation to a certain line segment.

While constraining the movement of the pointer, the Taskview panel will lock the coordinate values that are not being modified. For example, if using a horizontal constraint, only the X value changes, while the Y and Z values remain at their original relative or absolute coordinates, depending on whether relative mode is active or not.

File:Draft Constrain Shift Taskview example.png

Taskview when using a horizontal constraint while holding the Shift key

X, Y, Z constraints

Press one of the X, Y or Z keys after a point to constrain the next point on the specified X, Y, or Z direction. Press the same key again to release the constraint.

Pressing X or Y is equivalent to holding Shift and constraining horizontally or vertically, respectively.

Taskview when using a vertical constraint after pressing the Y key