Topics created by edyuyu

@edyuyu said:

Hi Mac1,

thanks a lot for your help.

i seem to have trouble opening Sketch Mac1A. could you please resend it?
I understand the procedure and it would be applicable, for tapering the model, i mean. The trouble is the tapering has to be specific in terms of dimension, from 5m to 3m. I saw that yours was approximately right in the 1B file you sent. but i need it to be exact. I just can't seem to work it! also, how do I render a face as a wireframe? thanks

Update for you:
Remember the cutting plane in that original mac1B model was too small to cut the total extent of your model. Therefore when you make that plane bigger the high side cut gets higher and the lower gets lower. Based on you model extent the cutting plane angle must be arctan (2/d) where 2 is you height differential and d is distance
between those two points. Instead of trig you can set construction points or ref lines and then rotate the plane untill it goes those two. I would use trig since it is so easy. Note make sure you make the plane a group else you will get a sticky geometry issue.
May quick check indicates the present plane is 7.595 degs but you need 6.874 degs. You have 590 vertices in that curve and that is WAY too many and makes setting accurate point difficult

Update 19 Feb 2012:
Update 20 Feb 2012:
Re-looked at the issue of problem getting the 5 and 3 m elevation values. The problem is the asymmetric surface will have those values occurring ~1 or at ~ most two places in the model. You can set either one very accurately, but you have to find where the fore mention points occur by inspecting you model to ID the verticals. You can use the text tool to find the max extents of the model to ID those points. I have not found a work flow that yields the 3m exact for a 5 m exact. The best I have done is [*][b]3.01390892m now ( 3.009330837m)with an angle of [*]6.76116898 degs now (6.776825767 degs)cutting plane slope and a ( point separation => L )value of 664.163112". These numbers change because I failed trig 101,. The angle should be now Asin( d/L) not Atan(d/L)
There are some very good modelers commenting to your post and hope they find what I am doing wrong. This maybe be a 32bit single float precision issue. [/b]

Hi, Thanks for all your help so far.

Speaking of that same complex shape, I have been able to draw it to some specific dimesnsion using beizer curves.
However, the edges did not become a face as I had thought they would.

I have tried to trace it using the freehand tool, but this is extremely difficult and the edges are really rough. i also tried turning drawing a polyline around it, but it gives a whole different shape altogether.
Any suggestions, please? This is really frustrating.