NURBS, Arrrgh!

[stunndman]

not sure if it's the same - but check out mike thomson's car tutorial available on http://www.blissdd.com/MikeThomsonWRX.htm

basically you don't really need to merge all patches to get rid of visible seams - if you construct your surfaces carefully (adjacent surfaces from the same curve and so on) and adjust the NURBS tesselation attributes modeling and rendering with patches will be just fine - be aware of tangency - and check out the square tool which does take care of tangency between adjacent surfaces

[placid]

Yeah that's the gmask one he was looking at and yes I'm having a tough time too with nurbs using that tutorial. It isn't beginner friendly.

I'm also try to make a car... just for fun. I did it in polygons but it looked TERRIBLE. Maybe I should post it up and get help from everyone. But if you get desperate I'd use polygons. I basically my entire car in about an hour. I've spent several hours on nurbs and still can't get it to work for me. so yeah I recommend poly modeling if you run out of three weeks.

[Projectkmo]

well... without more info... I;m not sure if this will help or not..



need to line up the Isoparms...match the number of UV
Spans on the various Surfaces....so they line up from surface
to surface. The Hood has one Isoparm from left to right...
But...the Fenders have 3 trying to meet that one. I believer after
you select one of the surfaces you can then go to Edit Nurbs> Rebuild Surface
to change the number of UV spans. Carefull though....because dropping
down in spans might make your original surface turn to ass.

[MasonDoran]

it will be impossible to join ALL of the surfaces...so only do so with the bigger/ more obvious patches. If you want the edges to line up...use the stitch edges tool, which will line the seams up without actually attaching them.

[NeoGSR]

Ok new question. Im finally starting to get somewhere. How would I go about bringing up the top of the bumper to get the shape? Would it be easier to make seperate surfaces and rebuild together, if so how? Or is there an easier way. Below is an image of how far Im at now and the arrow is what Id like to build.

Final question, on the front bumper I projected a curve onto the surface to cut out the grille. But I would like to extrude in the trimmed edge, which I did but they are not connected, an easier way?

Hope this all makes sense. Thanks so much for the replies Ive gotten so far, its helping me out.

[MasonDoran]

it is recommended to build the entire fender....and trim the wheel well....then use the curve from the top part of the fender...the curve from the top of the bumper...and two more curves...one profile for the hood...and another where the hood meets the windshield....with these 4 curves use the square tool to get 1 surface with curves.....then cut up the surface or duplicate surface curves and delete the surface and then tweak until isoparms are good.

A good habit to practice is build the large shapes FIRST...then do details last with trims and fillets because these will depend on the curves/surfaces of the large surfaces. You may have to delete the gril....create the hood and fender....then trim out the area for the grill and wheel well.

2nd tip...a VERY nice function is the project tangent option under edit curves. You need a curve and a surface to use it....but gives you supreme control over how the surfaces get really subtle and nice curves...which you see so often in cars

[placid]

You give good tips 2byts. Write a tutorial!

[MasonDoran]

i wish i had time to do a tutorial....but once u get used to nurbs...they can be really nice. I grew up on illustrator and freehand....so curves are refreshing compared to the constant push pulling of polys.

[MasonDoran]

one thing i have noticed is the square tool is probably the most versatile of tools...It needs four curves with all end CVs snapped together....but the none of the curves have to have uniform parameterization....the square tool has the ability to rebuild each curve to its corresponding curve(make sure you select the curves in a clockwise or counterclockwise direction), and it also as the ability to create tangency...(a smoth blend with an adjacent surface)....and all of the functions are built into its history node! so just select the node in the channel box and hit "t" or show manipulator...and with this tool it becomes very easy to build your surfaces.

Somtimes i am in a situation where i have only 3 curves...this is when i use the birail tool....and at other times you work your way into a corner with only 3 curves.....and this is when the boundary tool is a life saver.

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