3D Modeling

[tcxhb]

::SPAposition fp=::SPAposition(0,0,0); ; ::SPAunit_vector v=::SPAunit_vector(1,2,3); ::STRAIGHT *line =new ::STRAIGHT(fp,v); savelist->add(line); why i can not see the line on while opne .sat 已知点和向量 做直线 为什么.sat 打开看不到直线呢？ 2100 0 2 0 16 xxxx ACIS 21.0 NT 24 Tue Mar 01 20:55:13 2011 1 9.9999999999999995e-007 1e-010 straight-curve $-1 -1 -1 $-1 0 0 0 0.2672612419124244 0.53452248382484879 0.80178372573727319 I I # point $-1 -1 -1 $-1 0 0 0 # End-of-ACIS-data

[asdf]

Based on the sat file you included, I think the line is there.  If you are trying to open it in acis3dt or another application, you need to make sure it facets the curve you made.  It might be useful to make an EDGE rather than just a straight, by using api_mk_ed_line (please see http://doc.spatial.com/qref/ACIS/html/group__CSTRMAKEEDGEAPI.html#g6233202298c0bbcf3514a2b420254fa6).  This EDGE should be put into a wire body using api_mk_ewires (please see http://doc.spatial.com/qref/ACIS/html/group__CSTRMAKEWBODYAPI.html#ga6d41a2028c2e51efbcd92830b615c29). 

Whenever possible applications should use topology (FACE objects and EDGE objects) in preference to geometry and generally BODY objects are the prefered version of topology.  Our scheme application and other applications may not notice that geometry is there if it is not placed in a BODY.

Finally, to make sure you can see the edges make check that the application you are using to view the file can render edges.  In acis3dt.exe this means using the commands (view:gl), (view:edges ON) and (zoom:all).

hopefully this helps.

Eric

[tcxhb]

thank you very much！

i know how to create edge by tow point

but now  i just want to find the  tangent  by one point and the  tangent direction。。so can you help me

（and sorry for my poor english   thank you very much）