Defining surfaces and other new questions....

[Lucky1]

Originally Posted by lisa

I made this short video showing some of the tools, maybe this might help:
http://www.independentdeveloper.com/files/curves.wmv

Oh, also the spline tool is also handy for creating smooth lines.

Wow, what an amazing video, thanks! I watched it many times. If this program can do that then I'm pretty much sold. But I still need to figure out how that happened.

When I tried the same thing mine doesn't work. I did like you and laid down 3 vertecies, and then chose the Object and tried to add subdivisions, but my top left view didn't change, as seen in the first picture below. I think it was fine yesterday, but now....?

In the second picture I am showing how even the 3D view, which "accepted" the subdivisions, still filled in to the pointed middle point. This is a bit different than what my other model did, but it gives you an idea what I was trying to describe.

Sorry to get you bogged down like this.....but thanks again.

Wes

[lisa]

Originally Posted by Lucky1

Wow, what an amazing video, thanks! I watched it many times. If this program can do that then I'm pretty much sold. But I still need to figure out how that happened.

Here's a quick walk-through of the video:

- I draw a polyline using the polyline tool
- I subdivide the polyline to 3 division levels using Object > Subdivide +
- I extrude the polyline in the top view to give it depth.
- I temporarily turn off subdivision preview so I can see the underlying control mesh.
- I convert my shape from polylines to polygons; there's an extra surface that only shows up as a polygon.
- I delete the extra surface to smooth out the shape.
- I switch subdivisions back on with the 'd' key.
- I switch to vertex mode, and just play with the curve a little.
- I select two vertices along an edge and using Vertex > Insert Vertex, I add a new vertex to the surface. Then I repeat for the opposite edge.
- I select the two vertices I just added, and click Vertex > Slice Surface to cut the surface along the line formed by the vertices.
- This gives me another control point, so I play with the curve some more.
- I select some vertices along the front of the shape in counter-clockwise order, then use Vertex > Create Ordered Surface to make a new surface. I do the same thing again on the back of the curve to give it some volume.
- Finally, I select a row of surfaces along the middle of the curve and use the "Divide Loop" plug-in to slice the whole row in two.

Originally Posted by Lucky1

When I tried the same thing mine doesn't work. I did like you and laid down 3 vertecies, and then chose the Object and tried to add subdivisions, but my top left view didn't change, as seen in the first picture below. I think it was fine yesterday, but now....?

Subdivision preview probably got switched off for your orthogonal windows; check the menu. There's a hotkey for it on the keyboard 'd'. You probably just bumped it. I accidentally bump it all the time when I'm reaching for the 's' key to switch to surfaces mode.

Originally Posted by Lucky1

In the second picture I am showing how even the 3D view, which "accepted" the subdivisions, still filled in to the pointed middle point. This is a bit different than what my other model did, but it gives you an idea what I was trying to describe.

Weird. Try switching your surface from a polyline to a poly or vice versa. You might have an extra surface in there you can't see. You'll see I had that in my video, when I extruded I ended up with an extra surface that was making my curve ragged until I deleted it. I'd bet you've got something similar.

[Lucky1]

Thank you again so much. I don't know if I'll have a chance to try it tonight,
but as soon as I do I'll let you know.

Again, thank you very much.

Wes

[Lucky1]

Thanks again Lisa, and ya, I had hit that 'd' button. I use 'Alt Z' to delete a lot and must have struck it in my madness....hehe.

Originally Posted by lisa

- I draw a polyline using the polyline tool
- I subdivide the polyline to 3 division levels using Object > Subdivide +
.

Now this is what I did, and now with the subdivision back on it works right, but no matter what I do, I can't get it to fill in only to the curved line.
I even tried the Poly and Polyline buttons and it didn't help.

I have to admit, I'm not sure what the purpose is of the rest of the steps...are they required everytime I want to make a 2D curve?

So to recap, to make my little Ice Cream Cone, I do the above and get it nice and rounded. I can even get it to look ideal in all views.
Then I add the bottom part, the V.
I select it all and add a surface to it, but no matter how I do that, it's always a point at the top.

I cannot see another level or part, it looks like a cone in wireframe, but when it fills in it looks just like the screenshot I posted earlier.

Any idea how I can make my little cone?

Thanks!
Wes

[lisa]

Anytime!

Originally Posted by Lucky1

I have to admit, I'm not sure what the purpose is of the rest of the steps...are they required everytime I want to make a 2D curve?

Nah. I was just fooling around so you could get some ideas for later. Just the line and subdivide are required.

Originally Posted by Lucky1

So to recap, to make my little Ice Cream Cone, I do the above and get it nice and rounded. I can even get it to look ideal in all views.
Then I add the bottom part, the V.
I select it all and add a surface to it, but no matter how I do that, it's always a point at the top.

I'm still not sure what could be causing that, all I can figure is there must be an extra surface in there hiding.

But here's how I'd do it:

- Draw a 3-point polyline to make the curve at the top of the cone.
- Extrude the polyline.
- Select the entire object and switch the surface mode from polyline to polygon and delete the extra front or back-facing surfaces.
- (Optional) If you want the cone to have a super-sharp point, select Object > Commit Subdivision. This will lock the subdivisions in place as they are, making them uneditable, but will allow the rest of the shape to be non-curved. Otherwise, if you don't want to commit subdivisions, you can still make the cone fairly pointy by adding a second set of vertices near the tip.
- In vertex mode, highlight the two vertices at the top edge of the curve and select Vertex > Extrude Edge. Drag the vertices down to make the point of the cone.
- Repeat using the bottom two vertices.
- (Optional) To weld the point of the cone, highlight the two vertices on the left and click Vertex > Snap Together. If you have a lot of vertices, you can also use "Snap Together by Distance" with an appropriate radius to do several at one time. Repeat for the right side. Then click Object > Optimize Vertices.

I also recorded two quick videos to illustrate better.

With committing subdivisions (super-sharp point, but non-editable):
http://www.independentdeveloper.com/...commitsubd.wmv

Without committing subdivisions (editable curves):
http://www.independentdeveloper.com/files/nocommit.wmv

Note: the closer you move the two points together at the tip, the sharper the curve. Also, it was completely sharp before I welded it, all depends on what you want to achieve.

[Lucky1]

Thank you so much Lisa, you're a gem.

Well I'm officially in the club....I bought the program. What you showed me is just
amazing, and I think this program has about the right degree of complexity for me.
Though I still hardly know how to use it....I just hope I can get to the point where I
can do what I want with it, and I think with practice I will be able to.

Now your videos are just amazing (and fun to watch!) but perhaps we could go a
little slower and not use the extruding feature just yet? You see, the wireframe
model I am trying to make...well...I just think it would be easier to solve my problem
if we kept that off for now.

See, I have made a wireframe model and now I just want to curve one or two
lines, and then put a surface on it. Can we do that on each line I want without
making them 3D?

Let me put it another way perhaps.

Below demostrates my confusion, I will tell you how I did it.
-I draw a 4 point polyline to create a square shape, then doubleclick on the last point
-I highlight the entire drawing and select Subdivide+ 3 times
-I then choose "Select-Vertex"
-I then select the entire object and go to the Vertex menu and select
Create Convex Surface....and this is what I get.

So again, my problem is: what do I do when I have a complex drawing and all
I want to do is curve a line and fill in the panel?

Thanks again!
Wes

[lisa]

Ah, got ya! Ok. Finally just clicked what I think you're trying to build.

You've almost got it. Here's what you need to do:

- Do as you are presently, and make your four-point polygon
- Subdivide three times
- Make sure your curve is as you want it, then click Object > Commit Subdivision
- Under surface type, click Poly

That should give you a tear-drop shape that's filled in... since it was a polyline not a polygon, you don't need to use create convex object because the surface already exists.

[EDIT: little clarification since I know we've been talking about creating surfaces all along... if it's just a polyline, not extruded, it's effectively a 2D shape. AC3D allows any number of sides in a surface, so practically any 2D shape can be treated as a surface. If your shape was 3D, you'd like need to use convex shape or ordered surface to fill in the surfaces. I hope that makes sense, I don't think I'm explaining it very well.]

[Lucky1]

Thank you! That helped immensely!

Originally Posted by lisa

[EDIT: little clarification since I know we've been talking about creating surfaces all along... if it's just a polyline, not extruded, it's effectively a 2D shape. AC3D allows any number of sides in a surface, so practically any 2D shape can be treated as a surface. If your shape was 3D, you'd like need to use convex shape or ordered surface to fill in the surfaces. I hope that makes sense, I don't think I'm explaining it very well.]

No problem, I understand.

Speaking as someone really new to this (like that isn't obvious) it would really be good if the terms used were clearly defined somewhere. To a newcomer we don't even know what the difference is between a "Polygon" and a "Polyline" you know?
There are a lot of terms new to me. If you have a link to where they're described feel free to post it.
I've printed out the manual but it's not really in there.

I am going to work on my model some more and see what I come against next.
Right now I'm going through my model to "Snap Together" a bunch of Vertecies I want to act together.
So I'll let you know how I come along.

Thanks again!
Wes