Friday, May 30, 2008

Editing Sketches

In the past few posts you have been introduced to 2D sketching in Wildcat CAD, and have learned about some of the basic sketch constraints you can apply to 2D features.  In this post I will briefly discuss how to edit various sketch features.

First of all, you can select any sketch feature by clicking on it.  It should turn red.  You can also click-drag a selection box around features.  Using this method you can select multiple features.  Likewise, by holding down the Command key (OS X) or the Ctrl key (Windows) you can click select multiple feature.  You can only edit one feature at a time.


Points are so simple, just grab the point and drag it to where you want it.


Lines can be edited in two ways.  First, you can grab the end of the line and just move that end around, or second, you can grab the line in the middle and it will move the entire line.  If you are moving the entire line then its orientation (slope) and length will not change just its horizontal and vertical position in the sketch.

Axis lines behave just like regular lines.  They can be adjusted from either end or positioned by grabbing the middle.


Similar to lines, there are two ways to edit circles.  The first way is to grab it anywhere on the circle itself.  This will allow you to change the radius of the circle.  If you grab the center point of the circle you can then edit the horizontal and vertical position.


If you are not familiar, a two-point arc is drawn by first clicking the center-point of the arc, then clicking the start of the arc, finally clicking the end of the arc.  In essence, the first two clicks define the radius, hence two-point.  A three-point arc is drawn by clicking one end point, then clicking the second end point, then finally clicking a third point somewhere else on the arc.  It takes all three clicks to define the radius of the arc.

If you grab any part of an arc itself you can adjust its radius.  The orientation and arc-angle will remain the same.  If you grab the center-point of the arc you can reposition it within the sketch.  As of now, there is no way to adjust the arc-angle or the location of the start or end point.  This is something I want to add down the road.


Ellipses have multiple adjustments that can be made.  First is by grabbing the ellipse anywhere on the boundary, except where you see the point on the semi-major and semi-minor axis, or on the center point.  This will allow you to reposition the ellipse.  If you grab the semi-minor axis point you can adjust the radius of the semi-minor axis.  If you grab the semi-major axis point you can adjust that radius and also change the orientation of the ellipse overall.

There is currently a "bug" that needs to be fixed in ellipse editing.  You have to be sufficiently zoomed in on the ellipse to be able to grab either the semi-major or semi-minor points.  Otherwise you will only be able to adjust the position of the ellipse.  If this is happening to you, just zoom in more on the point you are trying to grab.

Conic Sections

As of now you are not able to edit conic sections.  Down the road I plan on adding this capability.  Sorry!

Well, that's all for today.  There are just a couple more posts left on how to use the Sketcher Workbench in Wildcat CAD.  Keep an eye out on the Wiki for some tutorials.  I will also try to update these posts as I make fixes and enhancements.


No comments: