Modelling a site and pavement etc. in Viz4.

[STRAT]

personally, i think the most important thing in any modelling, particulaly site modelling, is matching every verticy up.

Every end vert, corresponding vert, joining vert etc MUST match up with the next. There must no be free verts or overlapping verts anywhere - this causes holes and un-even finished surfaces and smoothing problems when rendering.

 

If you look at my wire frame piccy i posted earlier you'll notice every single vert in the model connects exactly with the next, there's no free verts in there atall. This is the main reason i dont use solids, i surface and face everything.

 

I never 'layer' my surfaces because rendering problems l8r on usually occure. it's more time consuming this way but a super clean model is essential imho.

 

When i model sites i'll almost always model and face up contoured and hilly sites exclusively in acad.

for completely flat sites i'll draw all my site plan in flat 2d lines and arcs in acad first, then import the various elements into viz for extrusion or capping, again in viz, making sure ALL verts match up exactly.

I'll quite often re-import this mesh back into acad for further work.

 

another thing too - when trying to fillet lines and 2d polys in acad you occationally get the message 'unable because they're non co-planar'.

There is a method around this. You CAN fillet sloping lines and create 3d sloping fillets in 3d space even whilst keeping the UCS at world. (i nearly always try to keep the UCS in world).

 

maybe i should write some tuts one day

 

Nisus does all his site modelling in max. Why not ask him on his methods?

 

[ November 16, 2002, 02:05 AM: Message edited by: STRAT ]

[CHE]

Yes Nisus we want to hear what you have to say about this topic.....

[foxlee]

I think theres a couple of ways to go about this in Viz.

I use Shape Merge from time to time .Basically create a plane with couple of subdivs to cover site say 4 by 4.

Next convert to editable mesh, go to vertex subobject selection and lift each row of verts to desired height of contour , now you can take each individ. vertex and move it horizontaly to pick up curving contours.

Then apply meshmooth modifier to get soft sloping contours for site,.

Nxt collapse to editable mesh again.

Draw lines to represent pavements or raised parts of site, convert these to editable spline. before that adjust number of segments for the line to get a smoother curve, depending how close you are going to get to a curve you can vary this over the site ( its under general properties of lines)

Then select the contour plane and go Create> Compound Objects> Shapemerge,

Select the editable spline ( lines of pavements etc).

This will cut the lines onto the contoured plane, collapse plane to editable mesh again.

Next use the freeform selection and select all th e faces inside the pavement line , extrude to desired height. if you use closed line ot rectangle , the faces inside these will be automatically selected when when you go to face sub-object selection.

This method is super fast, but sometimes you need to clean up verts etc. and smooth some faces, by

selecting and going autosmooth at bottom of menu.

Seperate in diff materials while faces are still selected, Go down and select detach to split grass from pavement etc.

What is great is that your original spline remains and can be re-used to add extra detail.

Would like to know what method other people use in Viz.

[nisus]

to vizwhiz,

 

Instead of using a large cylinder, I recommend you use the 'plane'-object. You can make the plane as big as your model, but set the scale option to 10x or 20x. This way your 'zoom all extents' keep working fine, without you having to zoom in every time. Be sure to set the divisions to 1 instead of the default 4. This way you have only two faces instead of a lot more using a cylinder.

 

rgds

 

nisus

[proces2]

in response to excluding the ground plane object.

 

you certainly can do that:

select the object, right-click, choose properties, go to the radiosity tab, check Exlude from Radiosity.

 

The problem, most likely, is that there will be an obvious difference as to how the road looks versus everything else when you render. since it will only be receiving direct light and none of the skylight. I think you would also get the appearance that the sidewalk, curbs, other object may be floating above the roadway. what makes radiosity images so believable is the subtle heavier shadowing that occurs at object intersection. if you use your exclude method, you won't get that shadowing. if this is a small detail in you image, then you could just fix it with feathering/fill/gradient tool in Photoshop.

 

another option.

simply make a series of rectangular objects (as meshes) that roughly follow the roadway. don't worry about exact intersections and alignment of vertices between the curb and road, just make sure they clearly overlap. (this gives you a roadway and also limits the size of the object - and the number of faces created when it gets subdivided for radiosity)

when rendering you can correct any light leaks and bad shadowing by using regathering. speed up regathering by only having a handful of selected objects to regather (in object properties, radiosity panel, check or uncheck the 'exclude from regathering option').

 

also, speed up regathering by NEVER using the default settings. start at rays per sample=20, filter radius=12. then play with it from there.

 

*note to VIZ guys - there needs to be a include/exclude window for choosing objects to be used or not used in regathering (if you want 4 objects used in regathering - you have to select all 250 other objects and choose 'exclude from regather' - not quite the intuitive way of working.*

 

sean

[Richard McCarthy]

Matching EVERY vertice up?.. GOD, you must have a lot of free time.. haha

 

 

My method: (pardon me, I hope this is not autoCAD only forum)

 

 

I would just use Revit's Site tool, It's the most marveolous and wonderful tool ever existed. Draw a large Square (or whatever shape you want) with site tool, Start going in with and lay out your grid and put in your point heights (click to add point, and key in point height) or alternatively, just import your 3D TERRAIN contour from AutoCAD, it will mesh it into nice 3D terrain.

After that, it's just drawing in your Road and curbs with Site tool again from Plan View, Revit will Cut/Divide the road and terrain up by itself.

After that, Select the road (Road and Terrain become seperate entity by itself) and move it down a bit to create your road and curbs. Export to DWG or DXF for easy rendering in VIZ. (It will be as clean as Strat's model, all vertices are matching up.. without me manually touching them)

 

 

-RM

 

 

Originally posted by STRAT:

personally, i think the most important thing in any modelling, particulaly site modelling, is matching every verticy up.

Every end vert, corresponding vert, joining vert etc MUST match up with the next. There must no be free verts or overlapping verts anywhere - this causes holes and un-even finished surfaces and smoothing problems when rendering.

 

If you look at my wire frame piccy i posted earlier you'll notice every single vert in the model connects exactly with the next, there's no free verts in there atall. This is the main reason i dont use solids, i surface and face everything.

 

I never 'layer' my surfaces because rendering problems l8r on usually occure. it's more time consuming this way but a super clean model is essential imho.

 

When i model sites i'll almost always model and face up contoured and hilly sites exclusively in acad.

for completely flat sites i'll draw all my site plan in flat 2d lines and arcs in acad first, then import the various elements into viz for extrusion or capping, again in viz, making sure ALL verts match up exactly.

I'll quite often re-import this mesh back into acad for further work.

 

another thing too - when trying to fillet lines and 2d polys in acad you occationally get the message 'unable because they're non co-planar'.

There is a method around this. You CAN fillet sloping lines and create 3d sloping fillets in 3d space even whilst keeping the UCS at world. (i nearly always try to keep the UCS in world).

 

maybe i should write some tuts one day

 

Nisus does all his site modelling in max. Why not ask him on his methods?

[mzagorski]

Have you got an example of this that you have rendered... would be nice to see what youve done ) Sounds interesting!!! Must get my hands on a demo of Revit to check it out sometime.

[Guest versionseven]

Strat, perhaps I'm not doing it rite but cant seem to get the terrain the way you said. Keep getting a mesh only in alternate contour lines.

ie. if I got 5 countour lines, only get mesh between line 5 and 4, 3 and 2, closed 1. Between lines 4 and 3, 2 and 1, nothing!!

 

Also very keen to know how to fillet in 3D. Pissing the heck out of me when using Edgesurf.

 

Version Seven

[STRAT]

richard - nope, i havent got a lot of time, far from it actually. it's just i been doing this for so long day after day so i have super fast methods and modelling techniques. matching up all verts is essential imo.

 

AutoCAD isn't the ideal terrain modelling software anymore, but if it's a choice between Acad and max/viz then acad gets the thumbs up every time. LandCAD used to be ideal, but Revit sounds the mutt's nuts these days.

 

versionseven - edgesurf can be quirky sometimes if all end points on the splines aren't exactly matched up. even if they are matched up you may want to edit the spline and match up the end points yet again.

 

can you post up a picture describing your problem pls?

[Craig Ramsay]

This thread is really interesting I'm going to take a look at Revit.

 

I have been poly modeling my landscapes recently in Max. I make a box, convert it to an editable poly and extrude the sides to create the shape of the landscape in plan. I then pull the verts up to the desired heights and add a smooth modifier.

 

I would post an image but the upload utility does not seem to be working

 

Craig

 

[ April 28, 2003, 04:14 AM: Message edited by: Craig Ramsay ]

[STRAT]

craig - http://www.vi2.com/uploader

[STRAT]

yes, it's completely public

[Craig Ramsay]

Ok here it is:

 

[ferox]

Richard

lay out your grid and put in your point heights (click to add point, and key in point height) or alternatively, just import your 3D TERRAIN contour from AutoCAD, it will mesh it into nice 3D terrain.

What kind of interpolation do you use (Revit) for accuracy between points in Revit?

 

Is the model a grid mesh or a TIN model (as in Land Desktop 3)?

 

Does Revit provide any feedback or measurement of contour/slope/aspect/spatial accuracy? So that you could be certain of (for example) building height effects or visual effects from the whole development as shown in the final render? etc

[nisus]

CHE:

Yes Nisus we want to hear what you have to say about this topic.....

I must have missed something...

[Richard McCarthy]

what do you mean TIN model?

 

Well, the grid is what you draw in yourself to get the exact coordinate of the point (like the surveyors) and at the exact point, I just input Z-value point height. Revit will take care of the rest for Contours and stuff. You can sub divide the terrain into different parts (so you can have roads, curbs, etc)

 

This is screen grab from Revit of the Site terrain I done :

 

http://www.cgarchitect.com/forum/filepush.asp?file=Revit-3DTerrain1.jpg

 

http://www.cgarchitect.com/forum/filepush.asp?file=Revit-3DTerrain.jpg

 

http://www.cgarchitect.com/forum/filepush.asp?file=Revit-Terrain.jpg

 

-RM

 

 

Originally posted by ferox:

Richard

quote:

---

lay out your grid and put in your point heights (click to add point, and key in point height) or alternatively, just import your 3D TERRAIN contour from AutoCAD, it will mesh it into nice 3D terrain.

What kind of interpolation do you use (Revit) for accuracy between points in Revit?

 

Is the model a grid mesh or a TIN model (as in Land Desktop 3)?

 

Does Revit provide any feedback or measurement of contour/slope/aspect/spatial accuracy? So that you could be certain of (for example) building height effects or visual effects from the whole development as shown in the final render? etc

[Brett]

I wouldn’t be afraid of using the Viz/Max Terrain tool. You must understand grading and you must optimize where you can and identify where you cant. After you use it a few times its easy as pie. I am modeling a large Hospital campus with it and after auto-edging the site the model spins around in the viewport in real time.

[Brink]

Brett

 

What do you mean auto edging the site. I am working on a park/residential development and I am not looking forward to modeling all the street curbs. I used the terrain tool and boolan commands to create the expanses of grass but now I hae to creat the curbs. Would that auto edging help me?