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rhino:capproblems [2016/03/09] |
rhino:capproblems [2020/08/14] (current) |
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+ | ====== Problems Capping Objects ====== | ||
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+ | >// | ||
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+ | **A common question** on the Rhino newsgroup is //"Why didn't my solid extrusion get closed?"// | ||
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+ | In the case of the **Extrude** command, Rhino currently doesn' | ||
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+ | In the case of the **Cap** command, you get a message **unable to cap that object**, which isn't very helpful to diagnose the problem. | ||
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+ | =====Extrusions that won't cap...===== | ||
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+ | ====Check for bad objects first==== | ||
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+ | The following is based on having valid objects. | ||
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+ | ====OK, my objects are good. What's wrong then?==== | ||
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+ | Rhino needs to have a closed, planar curve to create a cap surface. | ||
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+ | **// | ||
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+ | 1) the curve being used isn't closed, or\\ | ||
+ | 2) it isn't really planar. | ||
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+ | ====Not closed==== | ||
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+ | If there is no closed loop, Rhino cannot create a complete trim curve to create the cap surfaces. | ||
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+ | <color darkslateblue> | ||
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+ | * Use the command **SelOpenCrv** and see if it selects. | ||
+ | * Use the command **SelClosedCrv** and see if it doesn' | ||
+ | * Select the curve and look in **Properties> | ||
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+ | There are many methods to close an open curve, depending on what the problem is... | ||
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+ | <color darkslateblue> | ||
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+ | The commands **CrvStart** or **CrvEnd** will place a point at the start or end of the curve, which is where the opening will be found. | ||
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+ | You may then turn on points and try moving one endpoint on top of the other with point snap or otherwise edit the object to close it. | ||
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+ | ====Not planar==== | ||
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+ | If you determine the curve __is__ really closed (it didn't select with **SelOpenCrv**, | ||
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+ | <color darkslateblue> | ||
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+ | You can use Project to **CPlane** or **SetPts** and set the curve to all the same level. | ||
+ | |||
+ | ====Important note==== | ||
+ | Sometimes curves can be both **open //and// non planar**... | ||
+ | \\ | ||
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+ | ---- | ||
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+ | =====Existing objects that won't cap===== | ||
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+ | A parallel to an extrusion not capping is an existing open polysurface that you think should cap but doesn' | ||
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+ | In that case, the **// | ||
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+ | It may be open if the polysurface isn't fully joined. You can turn on naked edges to see if there are other naked edges besides the open edges to be capped. | ||
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+ | Or, the opening you **// | ||
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+ | Both of these cases will require a little more extensive repairs than a simple curve. | ||
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+ | * In the first case, you need to fix the surfaces so that they join up without any naked edges, except for the opening(s) you want to cap. | ||
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+ | * In the second, you need to find where the loop is not planar and fix the offending surfaces so they do form a planar loop when joined. | ||
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+ | //Hope this small explanation makes someone' | ||
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