POV-Ray : Newsgroups : povray.tools.poser : Flying a flag in Poser: howto : Flying a flag in Poser: howto Server Time
29 Nov 2022 13:22:43 EST (-0500)
  Flying a flag in Poser: howto  
From: Thomas de Groot
Date: 7 Aug 2008 05:08:00
Message: <489abb70$1@news.povray.org>
So you want to fly a flag for one of your POV-Ray scenes and you think Poser 
is the right place to just do that. You are correct.

However, like I discovered soon enough, there is a glitch that I took some 
time to solve properly, there being no tutorial available for this 
particular case and - surprisingly - no help available at the official Poser 

So, this is what happened and how I solved the glitch.

1) I made a flag (in Silo) with a couple of straps to hold it to a flagpole. 
Made a flagpole. Exported as .obj and imported into Poser.

2) I set up a simulation in the Cloth Room, taking care in particular to 
define the straps as Constrained Group, as they should stay in place around 
the flagpole.

3) I ran the simulation and discovered to my amazement that the flag slipped 
down the flagpole, the straps flying lose at the end. In my believe (and 
experience with clothes) this was not how a Constrained Group should behave. 
I ran the Poser curtains tutorial and could not find a clue about what I was 
doing wrong. So I went to the Poser7 Forum and stated my question, but no 
answer or solution was ever provided. Visibly, nobody had any idea (or 
nobody cared enough...).

4) I examined more in detail the curtains from the Poser tutorial and 
discovered at last one crucial difference: the curtain straps were attached 
at both ends to the curtains. In my flag this was not the case, having 
always assumed that one should avoid modelling objets where some edges could 
join more than two surfaces. So, this was the reason why my straps came 
loose in the simulation.

5) I corrected the model and ran the simulation again. This time, the straps 
stayed in place but the flag still slipped down the flagpole!

6) I put a stop on the flagpole (a small cylinder perpendicular to the 
flagpole) just below the flag and ran the simulation again. Lo! Everything 
was allright and the flag was flying very convincingly.

7) I exported one of the frames to POV-Ray and commented out the small stop. 
Perfect. The result can be seen in my latest contribution to the TC-RTC.


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