Digital Cities In H9

Joined: 20 Sep 2007 Posts: 2

Hello

First off, fantastic DVD, I've learned so much about Houdini, however, I've been trying to follow it in H9 and have had so much success but I've had problem with the circle point operation for converting poly to nurbs.

Unfortunately I'm not experienced in Houdini to work out other methods that work, right now what its throwing out is
Warning : "The curve was reduced to order 2 for the given parameters"

Error: "Resulted in a singular system of equations that could not be solved. Please make sure there are no coincident points"

And that means I cant carve the building on top of it and leaves me stuck. I've tried to convert it to nurbs using a convert sop and then join the edges, but that creates a weird result and again is totally unusable.

So I was wondering if you had any workarounds to this problem in H9 yet?

Joined: 15 Nov 2006 Posts: 29

hi, this looks like a very little pb.
could you give more details: where exactly in the dvd is the pb ( which lesson, which moment in time) , and maybe a quick snapshot would help.
thx

Joined: 20 Sep 2007 Posts: 2

http://img183.imageshack.us/img183/3633/houdidimn2.jpg

Here is the screen grab of the problem. I cant get the final city in the example file to work either, maybe a change in H9 to H8. I can restructure it to make it what I have before crawling the buildings out, but wont view the final.

So it breaks when trying to turn the city to nurbs, early in the DVD, just after the whole city is cut into streets and had the small primitives deleted.

The whole city works in the view port when I view it, but when it came to crawling the building along the curves, it just doesnt work and I haven't been able to progress.

Joined: 15 Nov 2006 Posts: 29

yes, that's what i thought. in the delete6 sop, you have something that refers to the copy2 sop which is downstream in the graph
the expression is:
`stamp("../copy2","ccy",279)`
but when you haven't used the copy sop yet, you have to set the default value ( here i set it to 279, which is a mistake) to another value ( cos there may not be 279 or more primitives.
( i read in the delete5 taht there's is 278).
so type f.Ex: `stamp("../copy2","ccy",20)` anything that is <278.
Otherwise, if you don't do that, in delete6, you will have no geometry ( cos it keeps only primitive no 279 which doesn't exist) ---> resample2 will have no geometry ----> circle1 whose number of points is determined by the number of points of resample2 will have 0 points - or 1 which isn't enough to build a circle.

NB: this is not a h8->h9 conversion pb.
btw: the whole geometry at the end take a long time to compute cos it's heavy. You can go step by step starting with smaller numbers of copies.

hope this helps.
thx for the remark, we will correct that

Site Admin Joined: 14 Nov 2006 Posts: 247

david, do we have to update teh project files?

Joined: 15 Nov 2006 Posts: 29

Yep, Chris. Plus what i will do is to test the scene on h9, and provide a h9 version of the file so that people can seamlessy work on h9 with it.
I will do that for the lsys as well i guess.

-d