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MrChristopherSL
01-03-2005, 11:33 AM
I'm evaluating LW right now with 7.5 discovery edition. I'm quite familiar with polygon/subdivision surface modeling (I use Wings3D quite often) and am trying to figure out how LW compares for modeling. So far I'm a bit confused by some of the tools.

I create a cube and want to extrude a face along the faces normal. So I select it and then invoke the Extrude tool. When I extrude the face, the faces of the extrusion are inverted. Why is this?

Thanks

Chris

robewil
01-03-2005, 12:09 PM
Flip the polygon first (f key) and then extrude. Extrusions are designed to go the opposite direction of the normal.

MrChristopherSL
01-03-2005, 01:18 PM
When I flip the face first, it disappears. So I then do the extrusion, but the extrudded part is disconnected from the rest of the mesh. In Wings (and C4D), I simply select the face and extrude. The LW Extrude function seems really odd to me.

Thanks

Chris

robewil
01-03-2005, 01:43 PM
When I flip the face first, it disappears. So I then do the extrusion, but the extruded part is disconnected from the rest of the mesh. It sounds like you are extruding in the perspective view. I would suggest extruding in one of the 2D views for accuracy. You will always see the polygon there. You can make your surfaces double-sided temporarily if you must extrude in the perspective view.

As far as it being disconnected, that doesn't make sense unless you had cut out the polygon. If you continue to struggle with this, post a screenshot showing what you are doing.

spec24
01-03-2005, 02:09 PM
try using the bevel or smooth shift commands instead. Makes life a little easier.

MrChristopherSL
01-03-2005, 03:06 PM
I've got a couple screenshots but I'm not sure how to attach them to ths message. But it's really simple.

Start a new document.
Create a basic box.
Select a single face.
Active the Extrude function.
In any view, click and drag.

The new geometry is inverted compared to the original geometry. The Normal indicator for the extrusion is going the opposite direction from what the normal indicator of the extruded polygon was.

I'm using 7.5d on MacOSX. I can save the object for others to inspect if they want.

Thanks,

Chris

robewil
01-03-2005, 03:19 PM
Start a new object
Create a basic box.
Select a single face.
Press 'f' to flip polygon
Activate the Extrude function.
In any view, click and drag in a direction away from the normal.

MrChristopherSL
01-03-2005, 03:45 PM
Yes, I tried that. When I do that, the extrusion LOOKS normal, but when I hit Tab for the whole object to go into subdivion mode, there is an obvious disconnection between the original object and the extrusion.

Chris

Digital Junkie
01-03-2005, 03:53 PM
Try useing the smooth shift tool (Shift+f) Sometimes this type of extrusion causes the poly to do weird things around its normal, so if you have problems just activate the smooth shift tool, right click (to create new geometry, you wont see it until you move the poly you shifted) then use the move tool to put the poly where you want.

robewil
01-03-2005, 03:56 PM
Yes, I tried that. When I do that, the extrusion LOOKS normal, but when I hit Tab for the whole object to go into subdivion mode, there is an obvious disconnection between the original object and the extrusion.

ChrisOkay, one more step. Before pressing TAB, press 'm' to merge points as extruding creates duplicate points.

Digital Junkie
01-03-2005, 03:59 PM
Just did a test. I think that for what you are trying to do you need the smooth shift tool. It would appear to me that Lightwave's extrude tool is for giving depth to flat polys (try it on a flat poly, or on text) So I think the smooth shift tool is for extruding new geometry off of other geometry. Or, to fix your method you would need to flip the extruded polys, then perform a merge (m) this should give the same result as the above directions (just more steps) Hope this helps. :D

robewil
01-03-2005, 04:28 PM
I think that for what you are trying to do you need the smooth shift tool.He never says what he's trying to do other than evaluate the software. Smooth shift has its uses but I think he's just trying to understand the use of the extrude tool.

MrChristopherSL
01-03-2005, 07:03 PM
Ok, thanks for your help. I was also able to contact a friend who know LW thoroughly and he said basically what you guys just said above. Apparently the Extrude function doesn't operate the same as Extrude in Wings or C4D. I tried the M key (Merge) and that accomplished what I was expecting.

This is sort of like learning a different language I suppose.

By the way, is there simple keyboard command for Deselecting elements? In Wings, I just hit the spacebar.

Also, is there a simple way of selecting an entire object? I ask this because when I import geometry from Wings using OBJ into LW, they all appear in the same layer. In Wings you can select the entire object by being in Object Mode. Nice and easy to select. So far I've not found a simple way of selecting a single mesh with one mouse click.

Thanks,

Chris

robewil
01-03-2005, 08:28 PM
By the way, is there simple keyboard command for Deselecting elements? In Wings, I just hit the spacebar.Hit the '/' key.

Also, is there a simple way of selecting an entire object? I ask this because when I import geometry from Wings using OBJ into LW, they all appear in the same layer. In Wings you can select the entire object by being in Object Mode. Nice and easy to select. So far I've not found a simple way of selecting a single mesh with one mouse click. By default, the entire object is selected. In other words, if you don't have any points or polygons selected, the operations you do will affect the entire object.

MrChristopherSL
01-03-2005, 09:44 PM
Ok, thank you, thank you. I knew there had to be something obvious.

Chris

Silkrooster
01-03-2005, 10:24 PM
One more thing, make sure no polys are selected when you press the tab key, If you select a poly an then press the tab key that effects only the selected polys, making them look disconnected from the rest of the object.
Silk

MrChristopherSL
01-03-2005, 10:26 PM
By the way, I thought I'd share with you a recent project I did using Wings3D as my modeler. That's why I asking all these questions because I'm trying to grasp how LW approaches modeling things I'm familiar with in another application.

Chris

http://www.stratacafe.com/image.asp?imageID=17106&artistimages=1&killnext=0
http://www.stratacafe.com/image.asp?imageID=16501&artistimages=1&killnext=0
http://www.stratacafe.com/image.asp?imageID=16397&artistimages=1&killnext=0

Digital Junkie
01-04-2005, 04:21 AM
WOW that is some exellent work, surprised I havent heard of 'Wings3d'. I'm sure that after you get a grasp of how modeler aproaches things you won't have any problems. :D

MrChristopherSL
01-04-2005, 09:17 AM
www.wings3d.com

It's an open source freeware subdivision surface polygon modeler that is really quite powerful. I know LW 8 has edge controls now, something Wings has had since its inception. You can do models there and import the cage into LW for further work. The nice thing about Wings too is that allows you to work with N-gons.

Here are some screen shots showing what the cage for the forklift look like in Wings.

http://www.stratacafe.com/image.asp?imageID=16063&artistimages=1&killnext=0

http://www.stratacafe.com/image.asp?imageID=16064&artistimages=1&killnext=0

http://www.stratacafe.com/image.asp?imageID=15844&artistimages=1&killnext=0

Chris