What a Mesh

Back to basics: Extrusion in AutoCAD part 5

So, now that we know how to use Path for the extrusion, let’s do some direct manipulation on the extruded object.

Let’s start by clicking it and see what we can do. We’ll see grips for the profile, grips for the path (in this case an arc), and another grip for position of the model. It is important to understand that there is no associativity between the arc and the object. The grips belong to the model, although they will be coincident with those from the arc before you make any changes.

In the following image you will see what I mean. As soon as we use that grip (center grip along the path), the curvature changes, and once we finish the operation, the arc is still in its place. After the operation, the arc is not relevant for the model itself.

The grips that belong to the profile can be moved very easily by using the Gizmo, into pretty much any shape that does not create self intersections. In this case, I just moved one vertex up, and the AutoCAD reacted in a very predictable way (for an extrusion). If you just wanted to move that vertex up, then there’s an extra step (use the command BREP). But that’s another post for another time.

If we were doing some very basic conceptual design, even after doing the extrusion, we have the chance to adjust the volume to another object. In this case, I’m moving the grip so as to be coincident with the height of the adjacent box, and that’s it. No need to worry at the beginning of the design. You can be as flexible as you want.

 

 

Now, I’ll just leave you with the final image. Just wanted you to know it was done with just two more clicks. Wonder how? Yes… you got it. That’s another post.

Alias Sketch for AutoCAD part 2 - 2d compositing

This is a video explaining 2d compositing between 3 images.

I'll also post an explanation later.

Alias Sketch for AutoCAD (part 1)

Let’s start to take a look at Alias Sketch for AutoCAD. The screen captures are from a beta version, so it may vary upon release.

First thing we’ll do is take a look at the workspace. Alias Sketch works in AutoCAD’s Paper Space, and instead of traditional Viewports, we’ll use the concept of Canvas, just like in any image editor.

Once you have an active canvas, you can start working with brushes. As you can see in the image below, the brushes react to different pressure with a tablet, so I encourage you to try one of these devices. The price has dropped, and you can find a great tablet for around 100 dollars. Actually, all I’m doing in the videos that will be part of these posts, is with a Wacom Bamboo, which is the cheapest of all. I also use a Cintiq, but the one I carry everywhere is the Bamboo, which is extremely portable.

As usual in other image editors, we have different brushes, like you can see in the Ribbon. In this case, check what you can do with the Marker.

 

 

Let’s check some of the Ribbon panels in the Alias Sketch tab (which appears as soon as you install the plug in).

The Workflow Panel is the one that controls the options for Canvas and Desktop. Speaking in AutoCAD lingo, you should think each canvas like a viewport, that can be activated, and then, whatever you do happens in that specific viewport. The main difference is that the canvas is not essentially a representation of the model space, but a place for editing images or sketching. In following posts we’ll see that we can access the model space through the canvas, but let’s go step by step.

The option Active Canvas lets you select which existing canvas in the desktop will you edit.

New Canvas is quite obvious. Once you select that option, AutoCAD will prompt you to draw a rectangle, just like when doing a new viewport.

New Canvas from Image lets you select a bitmap and start a canvas from here. This is an ideal scenario when you want to start to edit an image.

Resize Canvas deals with the size of the canvas. We’ll explore that option in a following post.

The next panel in the Alias Sketch tab is called Selection. It has two options, called Region and All. Select All will select the whole canvas (and will act on a specific layer of the canvas). It is important to clarify that every time I refer to layers, I’m not talking about traditional AutoCAD layers, but about layers of images in the canvas. That’s why what is normally called Layer Browser in image editing applications, here it is called Canvas Browser.

If you select the Region option, you will notice a change in the Editor (see image). The Editor is a context sensitive palette, so you will notice that its functionality changes according to the active command.

There are several options for selection, and you may know them all from other image editors.

You have different methods for selection, such as Rectangle, Ellipse, Polyline, Lasso and Magic Wand. Depending on the selection you want to do, you will choose different options. We’ll refer to them in detail in other posts, with specific examples.

The modes within the editor are three. You have the Replace Mode, the Add Mode and the Remove Mode. Replace Mode will deselect anything you have selected in the screen, and replace it with the new selection. Add Mode will add the new selection to the previous one, while Remove Mode will subtract from the previous selection.

Action contains two options, which are Deselect and Invert. Deselect will remove any selection you have on screen, while Invert will make an inversion in the selection. Maybe your scene has a rectangular floor plan and its environment, and you select this shape with the Rectangle option. Now, what you really want is to operate on everything else but the rectangle, so you will invert the selection. Smart selections will make you work really fast!

Too much information for one day J In next post, I’ll cover the Canvas Browser and go through an example of 2d compositing using three images.

Alias Sketch for AutoCAD - coming soon!

As I said yesterday, there's a class I'm preparing for AU called Taking 2D Beyond Documentation (ID218-1) . Paul Lebovitz is actually hosting the class, and I will cohost.

So what is this all about? As soon as this application is available, I'll let you know. I borrowed some screen captures and part of the description from my friend Shaan, but will also start to post tutorials in the following days.

Did you ever need to make a presentation with graphics coming from AutoCAD? For sure.

You probably had to use some of the many image editors that can be found in the market. But how did you take the linework in AutoCAD into those applications? I will not say it was/is difficult, but certainly disrupts the work.

And what if you wanted to use a 3d model in AutoCAD for some compositing? Well... you always had the option to render it, and then open the image in an image editor.

What if I told you that you will not need to get out of AutoCAD for these tasks?

This is one of the things I would have loved to use back in my architecture years.

So who is this application for? Anybody in industrial design, architecture, landscaping... pretty much everyone that needs image editing in AutoCAD.

Illustrate with Alias Sketch

Use intuitive pen-based painting and drawing tools such as pencils, markers, and brushes to create and adapt raster images in AutoCAD paper space.

The Alias Sketch Workspace

The Alias Sketch workspace is comprised of a single tab on the AutoCAD ribbon. Tool palettes, color editors, and browsers provide access to all the features you need to create illustrations in paper space. And if you want to experiment with new UI, it also works with marking menus!

Use intuitive pen-based painting and drawing tools such as pencils, markers, and brushes to create and adapt raster images in AutoCAD paper space. If you have a tablet, you'll be able to apply pressure too!

Layer and transformation features extend your power to explore and fine-tune your ideas. Display 3D objects as layers in an Alias Sketch raster image to trace or to provide rich composition possibilities.

• Draw Freehand Illustrations
• Create Concept Variations
• Create Compositions with 3D Models
• Trace 3D Models
• Create Concept Walls
• Annotate

 
 So, if you feel curious, and you are going to AU, check out this class! I'm sure you'll love the concept.

See you at Autodesk University

This week I'll be finishing details for my three classes at AU. Here's a detail of them. One of them is on AU Virtual, so if you are not going to Las Vegas and still want to take part of this, it's a great way to do so.

AU208-4 What a Mesh! Tips and Best Practices for Working with Free-Form Design in AutoCAD®

90-Minute Class

Class Description
This class will provide an exhaustive explanation of the new mesh functionality in AutoCAD, with tips, tricks, and best practices from the product manager who worked on this feature. Mesh modeling in AutoCAD has dramatically improved the power for achieving complex shapes, thanks to subdivision surfaces. During the class, we will cover different workflows for a better use of mesh modeling in different disciplines, with their respective links to other applications like 3ds Max®, Revit® and Inventor®. Learn how and when to convert from Mesh to Solids and best practices for the tessellation of Solids into Mesh. Explore different examples of successful implementations of this feature. We'll go through the steps for the creation of AutoCAD's Hero Image, which portrayed a mixture of mesh, surface and solid modeling.

AU9410-1 AutoCAD: Beyond 3D – Tap the Power of Visualization Tools

Virtual Session

Class Description

Creating a 3D model is only half of it! The real power of 3D is to communicate your ideas with materials, cameras, and walk-through animations. In this session we will tap into the power to define and apply visual styles that will quickly change the appearance of your 3D models. Easily orbit around your models, swivel the view, and even fly through your models! We’ll explore how you can record animations on the fly or by using a predefined animation path. Come to this session and learn how to give your 3D models a facelift!

Taking 2D Beyond Documentation

Class Audience

AutoCAD users who want to (or currently do) utilize additional creative tools such as Photoshop® for enhancing the design and communication process.

Class Description

Will explores creative methods that utilize Alias® Illustration functionality with AutoCAD® to extend documentation beyond technical drawings. So if you use Photoshop® with AutoCAD®, this is the class for you!

Key Learning

• Using Alias Illustration tools with AutoCAD®
• Creating design variations from existing imagery
• Blending 2D imagery with 3D models
• Advanced presentation of your design models
• Streamlining the digital pipeline

So, curious about Alias® Illustration? Check this blog in the next days and you will learn some details. You may even be tempted to take this class.

Back to basics: Extrusion in AutoCAD part 4

The last option to cover within Extrusion is Path. This will take four complete posts, but I think it’s worth examining the options very carefully.

Last time we talked about Direction, which would somehow do the same as Path, if the latter was a simple segment. If you have a polyline, 3dpolyline or spline, then Path is the right option.

Let’s see how it works.

First of all… where do we locate the path? Well, there are some rules for that.

Normally, the path will be located in a point that touches the profile. The path does not need to actually start in the profile, but it normally helps to better understand what you are doing. However, this may vary. You could have the path starting at a midpoint in one of the segments of the profile, or even have the path starting anywhere, and at some point intersecting the profile. Actually, the command will also work with a path which does not touch the profile! The result may not be too predictable, but there’s always a rule for that too (but not today).

Let’s assume that the path starts at the bottom vertex of this rectangle. Once we invoke the Extrude command, we need to add the path, since what we’ll see by default is the dynamic preview of the profile extruding along its normal. Once we access Extrude options (down arrow, right click if you use mouse sensitivity, or command prompt), we select Path, and then click on the entity which will act as path. And voila!

 

 

This is the before and after selecting the path (images above and below respectively)

Let’s see what happened in this process. If we go to a Top View, we’ll see that the angle between the profile and the path was kept. I have heard people asking why (in a similar case) the ending of the extrusion is not vertical. Well… that’s not the way the command works. If you need something like that, a loft between two profiles and a guide would be better.

Does this work in any case? Let’s try with this other arc, which starts almost tangent to the profile. Almost is the magic word here. Since it is not tangent, the command works perfectly, as you can see in the two images that follow.

 

In the following image, we can see a scenario where the command will fail. The path intersects the profile, and it will be impossible not to generate a self intersecting solid. That’s something that AutoCAD will not accept. Some applications can force the creation of a non valid solid, but that will lead to problems at some point.

 

One last case for today. The following path and profile don’t have any trouble in creating an extrusion. But if we move the path to the other end of the profile, it will fail, since the path’s curvature is smaller than the length of the profile, which will evidently cause a self intersection. Pretty obvious, but tends to happen, and sometimes in the middle of a very long day, we may oversee this kind of conditions that Extrude with Path needs for a successful operation.

In the two images that follow, the command succeeds, while it fails with what seems a small change in the starting conditions (last image).

 

 

Attend the See the Difference with AutoCAD 2010 Virtual!

If you have not had the opportunity to attend the See the Difference with AutoCAD 2010, you can still attend the Virtual event!

On Tuesday 17th (tomorrow/today, depending on when you read this), some of my colleagues and friends will be presenting, and you will also have the chance to meet me at the booth and ask me questions about modeling, rendering, or whatever you want in AutoCAD.

You can register to the event here

This is the agenda for the event.

If you go to the Exhibit Hall, to the Autodesk booth, you will be able to chat with me (Chat with Rep). I{ll be in the stand from 11am to 2.30 pm PST.

See you tomorrow!
 
 

Back to basics: Extrusion in AutoCAD part 3

Back to blogging, in this case continuing with solid modeling. As I said before, there may be little to say about the Extrusion command for advanced users, but some of you may find this interesting, and I would also recommend it to anyone that has not seen the enhancements after 2007.

The Extrusion command has an option called Direction. It can be accessed from the command prompt or by right clicking and getting to the in canvas menu (after having selected the profile and started the extrusion).

Why do we have that option? If you have a situation where instead of needing to do an extrusion along the normal of the profile, you need to do it along a certain direction, you would have two ways to do it. The long one is to draw a path and then select Path in the Extrude options. But if you have references that can be snapped, and the path is straight, then Direction is much easier, since you just need to select the first and last point of the direction of a non existent path.

Let's say you have two pillars, and need to create a reinforcement along the diagonal. These would be the steps:

In this case, I already have the pillars, and the profile to be extruded diagonally is already drawn next to the left pillar.

Once the Extrude command starts and we select the profile, if we right click or hit enter, the profile will try to extrude along the normal (in this case, vertically). That's when we right click and get to the in canvas menu, where we'll select Direction.

So, what points should I choose in order to get this result? Since the profile was a rectangle with half the width than the pillar, the first point to choose will be the profile's vertex coincident with the midpoint at the bottom of the left pillar. The second point will be the vertex at the top of the right pillar as shown in screen. It's quite obvious, since we need to select two points that will generate a path for the profile to move along.

That was easy! No more auxiliary lines for these situations. Just two clicks!

Now, we may need to edit the extrusion. Let's check its properties.

In the properties palette, under Solid Type, we see Extrusion, and we can change height and taper angle. In this case, height will be a vector along the path formed by the two points selected. Looks quite obvious, but in following postings, we'll see that an extrusion is not always such when we check the solid type. But I'm not going to steal my own thunder.

If we select the extruded object, we'll also see the grips that control the profile and the one for the height. As usual, this means that we can use direct manipulation in order to change the shape of the rectangle (as long as we keep four vertices, this works - meaning you can't add a new vertice), or we can also change its height by clicking on the control at the top of the extrusion and simply moving the mouse (or you can also type a specific distance).

And that's it.

You may wonder if there's a difference with making a path. We'll check that in the next post.