AutoCAD 2D image to 3D

[dlphnangel]

On my quest to change a 2D image into a 3D one I've found this to be the most helpful software so far. I am still trying to figure out how to change an image I draw (one straight side, the other has a few angles, meeting the top and bottom of the left side) into a 3D image that I can rotate. Does anyone know what steps I need to take? I've tried looking through some tutorials, but haven't found one yet for what I am trying to do. Also, as soon as I figure this out I will be trying to import an image into AutoCAD and want to change that into 3D as well, so help in either area would be great. The imported image would be just black lines with white background.

 

[TCARPENTER]

Hi dlphnangel,

I'm not real sure what you're working with here but, when I design aircraft, I usually start by hand (pencil and paper), and then scan the image into AutoCAD and then "trace" the scanned image in AutoCAD. After importing the image into AutoCAD, I create a layer called "Trace" and make its color red, for better contrast, and then, I find it helpful to set my polyline width to approximately the width of the scanned lines. This helps me more accurately trace the image. Once I'm satisfied with the trace, I'll unload the image I've scanned in, and then begin editing the polylines by setting their width back to zero, and in my case, begin smoothing them. In your case, I think, you may just need to close the polylines and then extrude them to make them a solid. If I understand your image you are trying to convert, it may share some line elements, if this is the case, you may find it easier to think of your line drawing as a set of blocks (like the old wooden ones we used to play with - I know I'm dating myself!) and create a polygon for each of the "blocks", and then extrude each polygon individually.

HTH
Todd

 

[dlphnangel]

Yeah that makes sense, I'm gonna give it a shot tonite. Do you know if it can be colored easily in Photoshop after it? What I am doing is taking a side view of crown moulding and converting that into a 3D sample of it. Then I want to take it into photoshop and add some color (I've mastered that much). But your thing sounds promising, so thanks TCarpenter! If anyone has another way, I'd love it try it as well!

 

[TCARPENTER]

Hi dlphnangel,

I'm sure it can be colored in with photoshop, I've never used photoshop so I can't really say. However, once you've converted your crown molding profile to 3D, you can apply materials to it and then render it. Many people use this technique and then import the rendered image into something like photoshop to touch it up.

HTH
Todd

 

[dlphnangel]

I'm a little confused with the polygon part though. I don't know if I can exactly make all those polygons for one image. Is there another way to convert the lines into a 3D shape? All I need to add is the depth.

 

[CarlAK]

I'm not sure I understand what your figure looks like, but it sounds fairly simple. Drawing it with 3d faces may be the easiest way to create a 3d object("3dface" is the command). Face can have 3 or 4 vertices (corners). You just need to know the xyz coordinate of each face corner. If you drew your 2-d figure with lines, maybe you just need to edit some line endpoints to give them z values, then you can draw 3dfaces by snapping to line endpoints.

 

[TCARPENTER]

Hi dlphnagngel,

Since you're drawing a crown moulding profile, you probably won't need to create multiple polygons, (I wasn't real sure what you were trying to draw - until your second post), you'll just want to create the profile out of polylines and then make sure the polyline is closed (otherwise AutoCAD won't extrude it).

HTH
Todd

 

[dlphnangel]

Thanks for the help. Guess you can't send me the images. Any steps or directions here as to what you think I should do would be great. Since you seem to have an idea of what I'm trying to do.

 

[TCARPENTER]

Hi dlphnangel,

Guess that was a no-no ...

Hhmmm... Try this link:

Cad Block Exchange, once you're there, on the left hand side you'll see a search box, (you may have to scroll down), but in the box type "molding" (no quotes) and press the search button. This should return 2 drawings, one of them is named "guimier_R2000.dwg." If you right click on the drawing, and then select "Save Target As..." you can save the file and then open it with AutoCAD 2000 or later.

In the modelspace portion of the drawing, you'll see a standard crown molding profile. At the command type "Explode" (no quotes, and its not case sensitive) and then select the crown profile. You will then have a series of arcs and lines. At the command line again type "Pedit" (again no quotes, and it's not case sensitive), and select any line or arc on the crown profile. AutoCAD will then prompt you with the following prompt [purple]"Object selected is not a polyline
Do you want to turn it into one? <Y>[/purple] - Press either the Enter key or the "Y" key to accept this and turn the selected arc or line entity into a polyline object. Once you have done this, AutoCAD will produce the following prompt: [purple]Enter an option [Close/Join/Width/Edit vertex/Fit/Spline/Decurve/Ltypegen/Undo]:[/purple] Type "J" or "Join" at this prompt (again, no quotes and its not case sensitive) and then press Enter. You will then see the following prompt: [purple]Select objects:[/purple] Here you will begin selecting all the arcs and line segments which make-up the moulding profile. When you are finished selecting entities, press Enter to end the selection process. You will then see the following prompt: [purple]Enter an option [Open/Join/Width/Edit vertex/Fit/Spline/Decurve/Ltype gen/Undo]:[/purple] - Now just press Enter to end the command.

The important thing to note here is the first item in the list of options, "Open". You'll notice in the first prompt after you converted your selected entity to a polyline, the first item in the option list was "Close".

This is important because when you trace your enitities in AutoCAD you [red]must[/red] make certain you have a closed polyline or the next set of commands will fail.

At the command line, type "Extrude" (again no quotes and its not case sensitive), and then select your crown profile. You will then see the following prompt: [purple]Current wire frame density: ISOLINES=4
Select objects: 1 found

Select objects:[/purple] Select the crown profile to extrude and you will then see the following prompt: [purple]Specify height of extrusion or [Path]:[/purple] Here, type in "120" (no quotes), and press Enter. You have now just converted a 2D profile into a 3D object. To see the results of what you have done, at the command line type: "VPoint" (again no quotes and its not case sensitive), and then at the following prompt: [purple]Current view direction: VIEWDIR=0.0000,0.0000,1.0000
Specify a view point or [Rotate] <display compass and tripod>:[/purple] Type "R" (again no quotes, and its not case sensitive) and then you'll see this: [purple]Enter angle in XY plane from X axis <270.00>:[/purple] Type 225 (no quotes), and press Enter. You'll now see: [purple]Enter angle from XY plane <90.00>:[/purple] Type 35 (no quotes), and press Enter. You should now see a wireframe representation of the 3D piece of crown moulding.

Now all you have to do is apply this same method to your profile you are trying to convert.

HTH
Todd

 

[dlphnangel]

When I type "pedit" I get the following list: Window/Last/Crossing/Box/All/Fence/WPolygon/CPolygon/Group

Also, I noticed as I was trying to trace it there isn't a freehand tracing icon, just lines. So I managed to trace it in another layer, but I don't know where to go from here, since my prompts are different from yours.

 

[dlphnangel]

I forgot to add it won't explode either (nothing that you wrote is appearing). So right now I have an object traced and don't know how to get from the tracing to a polygon. I'm using AutoCAD 2005 (the trial, b/c if I can't get it to work then I don't want to spend the small fortune on it).

 

[dlphnangel]

Latest update, I have the outline as a polyline, but when I extrude it goes inward, instead of outward (if that makes sense). Like if it were a square, instead of making a cube, it puts the 3D lines inside the square. HELP!!!

 

[TCARPENTER]

Hi dlphnangel,

Sorry I goofed and forgot to include the selection prompt when you type in "pedit". After you type "pedit", you should see your cross-hairs (in the drawing area) change to a small box - with this box, select one of the entities you've traced with. Then the prompts should either by the same, or very similiar from there. I haven't had the opportunity to use 2005 yet so the prompts may be slightly different.

Also, you will not need to explode any of the items you drew. The only reason I inlcuded that was if you wanted to try the download file - it was a block (sort of a rubber stamp in AutoCAD for entities you don't want to draw over and over) and had to be exploded to work with its individual entities.

The "free hand" option you're looking for in AutoCAD is called "Sketch". Right now, don't play with this, as AutoCAD is Vector based and "Sketch", creates a whole bunch of little vectors, so by doing it with the lines, you have done it correctly. When you use the "Sketch" command, you'll see your file size increase dramatically, plus your extrusions may not be as smooth as they could or should be.

HTH
Todd

 

[TCARPENTER]

Hi dlphnangel,

Wow that was fast!

If you are in plan view and you extrude and your result appears as though is extruding on the inside, you may be inadvertantly supplying a taper or draft angle - when prompted for this, use 0.

Also, there are a couple of settings for viewing 3D objects that could cause you to think they are moving to the inside, these are: ISOLINES and DISPSILH. Set ISOLINES to 0 and DISPSILH to 1. Then type "regen" (no quotes) at the command line and see if that improves your drawing.

HTH
Todd

 

[dlphnangel]

Alright, I had a polyline figure, but now it's not extruding at ALL. What the heck? It did it a second ago (inward, but none the less), and now nothing. Here's what I did:

Draw --> Polyline
Then I went and selected each corner of my figure, and at the end I right clicked and selected "close."
I then typed the command "extrude"
I selected the polyline figure.
Then Typed in 120 as the height (even tried other numbers)
Typed "0" as the angle.
And it says unable to extrude.

It was just working, but now it's not. Boy is this frustrating. Just when you think you have it, it doesn't work. AHHHHHH!

 

[TCARPENTER]

Hi dlphnangel,

Your polyline cannot have any self-intersecting curves, when you draw your polyline, you may want to make use of OSNAPS when you create your polyline. The close option of the pedit or polyline command can create self-intersecting curves depending on what, exactly you've left open. Best thing to do here is zoom in very close to your profile and examine any change of direction as these are the most likely culprits of this condition. When you find it, you can use "grips" within AutoCAD to reposition the intersection to make it non-self-intersecting. To use grips, simply select the polyline in the graphics area and you'll see intersections highlighted with small filled in squares (usually blue) and then simply place your cross-hairs over the box and left-click, if you located your cross-hairs close enough, the box will turn red (or maybe some other color) to let you know it has been selected. Then simply drag the box where it would correct the self-intersecting curve. Also, make sure you didn't try extrude an already extruded polyline.

HTH
Todd

 

[dlphnangel]

Sorry, but nothing that you said made any sense, except that I can't extrude somehing that was already extruded, or that polylines can't intersect (although I don't know how to tell either of these). I've only been working with this program for about a week, so I don't have all the stuff down yet, much less where to find it or what it does.

 

[TCARPENTER]

Ok....

Let's try this:

First, you know the drill - no quotes and the commands are not case sensitive.

Zooming in and out:

To zoom in with a window, type "zoom" at the command prompt, then will be presented at the command line with some options but you can ignore these, as the default option is "Window". In the graphics area, left-click on an area which would represent an upper right-hand corner of the area you want to zoom into. Then drag the "rectangle" AutoCAD is drawing on screen to what would be your lower left-hand corner of the new area. AutoCAD will magnify the view to fill the screen with the rectangular area you just selected.

To zoom back out, type "zoom" at the command prompt and then type "p" (for previous) when the list of options presents itself. AutoCAD will then take you back to the last magnification. If you are not seeing all of what you want, repeat "zoom" and "p" until you are out as far as you want.

To zoom to the drawing extents, type "zoom" at the command prompt, and then type "e" (for extents) and AutoCAD will zoom out or in to encompass all the drawing entities onto the graphics screen.

Grips:

Grips are usually automatic, just select any entity with your crosshairs - do this by just left clicking anywhere in the graphics area - NOT on an entity - and then if you move the mouse to the left, you will see AutoCAD begin to draw a rectangle with broken lines, this is called a crossing window. If you move the mouse to the right, AutoCAD will generate a rectangle with continuous lines, this is called just a window. Here are the differences: A crossing window only has to touch and entity to select it, whereas a regular window, must enclose the entire entity to select it. So, use either window (your choice) to select your drawn profile, and then you should see your "Grips" appear on your newly drawn profile.

Try these steps and let me know if that helps get you going or not.

Todd

 

[dlphnangel]

Well I got it to do the inner 3D thing, but when I put the "0" in instead, it doesn't do anything. I created a new layer, and outlined it in the polylines, then did all the extruding, and it didn't work. Any ideas?

 

[TCARPENTER]

Only if you can tell me more specifically what you mean by it didn't work.

Did you get any kind of error message?
Did you change your vpoint setting to look and see if something actually did happen?

A little more detail would be helpful.

Todd