Through the Interface

Updated version of ReCap Photo available for trial

After taking a look at Project Memento, last week, using it to manipulate a mesh I’d previously created with ReCap Photo, I decided to try out the latest update to the latter of these two tools. The first thing to notice with this new, improved version of ReCap Photo is that it has its own portal showing your active projects: The tool itself works in the same way: you simply select multiple photos in Autodesk 360 and select “Create 3D model” from the action menu. In fact, all I had to do to try this new version was to... Read more →

Drawing a figure of eight knot inside Tinkercad using JavaScript

Following on from my initial playing around with Tinkercad and its Shape Script implementation, I started to look more closely into what’s possible with the Gen6 kernel. I came across this recent blog post, which highlights the ability to make Shape Script implementation details public. The Shape Scripts shown in the post looked nice and complex, so I tracked down the model by selecting “Discover” inside Tinkercad and searching for “Brandon Cole”, the originator of these very interesting Shape Scripts. He published this design about 3 weeks ago, which I went ahead and copied (yes, shamelessly, but at least... Read more →

Creating a grid of columns inside Tinkercad using JavaScript

A little over a month ago, Autodesk acquired Tinkercad. Tinkercad is a 3D CAD tool that uses WebGL to display graphics directly in your browser. While this tool is primarily targeted at consumers – it’s proving very popular among the 3D printing community – I thought I’d check it out to understand its customization capabilities. If you want to get to know the capabilities of the Tinkercad system, I suggest taking a look at these step-by-step lessons. I personally just dove right in – the system is very straightforward to learn – but I’m sure there are basics that... Read more →

Finding a point on an AutoCAD surface based on X,Y coordinates using .NET – Part 2

As predicted in the first post in this series, today’s post looks at a slightly more robust and user-friendly approach for determining the point on a surface found by firing a ray normal to a selected X,Y point in the plane of the current UCS. Here’s the updated C# code that now includes an additional command called POXY (that’s a shortened form of PointOnXY, but will hopefully bring a smile to the lips of British readers): using Autodesk.AutoCAD.ApplicationServices; using Autodesk.AutoCAD.DatabaseServices; using Autodesk.AutoCAD.EditorInput; using Autodesk.AutoCAD.Geometry; using Autodesk.AutoCAD.Runtime; using AcDb = Autodesk.AutoCAD.DatabaseServices; namespace SurfaceIntersection { public class Commands { [CommandMethod("SURFRAY")] public... Read more →

Finding a point on an AutoCAD surface based on X,Y coordinates using .NET – Part 1

When I woke up this morning I didn’t expect to write a post on this topic, but then I found a kind email in my inbox from an old friend and colleague, Ishwar Nagwani, with some code he’d written and wanted to see posted. Ishwar had generated the test code in response to the following question from a member of the ADN team: This question is to get the corresponding Z of a surface/solid, given a point of XY. This refers to the absolute coordinate, instead of the point on param space. I seem not to find a direct... Read more →

Performing Boolean operations on AutoCAD solids using .NET

I looked back and couldn’t find a post covering this particular topic and so decided to put something together. It may well have been covered elsewhere (I admit to not having looked) but I felt like throwing some code together, either way. :-) To perform a Boolean operation between Solid3d objects inside AutoCAD, you can use Solid3d.BooleanOperation() on the primary Solid3d, passing in the secondary one. We want to implement commands for Unite (or Union), Intersect (Intersection) and Subtract (Subtraction). Only the last of these needs us to select a primary object explicitly – as the other two operations... Read more →

Creating a square AutoCAD box via the jig entity framework and .NET

After creating a frustum-shaped jig “manually”, refactoring the code while introducing the idea of an “Entity Jig Framework and then updating the framework and providing a number of usage examples, today’s post looks at a slightly more complex use-case: defining a jig to create a square (in X & Y) box by selecting opposing corners. It may sound simple, but it was actually harder that it sounds – especially when supporting the use of an arbitrary User Coordinate System. It also makes use of a “phase” type that we previously hadn’t needed, as we require point input for our... Read more →

Update to the AutoCAD .NET entity jig framework

In the last post I introduced a simple framework to make the definition of multi-input entity jigs more straightforward. A big thanks to Chuck Wilbur, who provided some feedback that has resulted in a nicer base implementation, which we’ll take for a spin in today’s post. Here’s the updated C# framework code that makes use of a simple class hierarchy for our phase definitions: using Autodesk.AutoCAD.DatabaseServices; using Autodesk.AutoCAD.EditorInput; using Autodesk.AutoCAD.Geometry; using System.Collections.Generic; using System; namespace JigFrameworks { // Two abstract base classes: one for all phases... public abstract class Phase { // Our member data (could add real properties,... Read more →

Jigging a frustum-shaped AutoCAD solid using .NET

As promised, here’s the cleaned-up code to jig a frustum inside AutoCAD. When I took on the task of writing this code – live, during the “AutoCAD Programming Gurus Go Head to Head” class at AU – I thought to myself “that should be easy enough – I’m sure I have some code to jig a solid on my blog”. Well, I did, but it turned out the code showed how to jig a box, and the code was in Python and Ruby but not C#. So I ended up having to code for my supper, after all. ;-)... Read more →

Examples of calling Dispose() on AutoCAD objects

To accompany the last post – which raised some questions around when and where to call Dispose() on objects created or accessed via AutoCAD’s .NET API – today we’re going to look at a few concrete examples. Thanks to Danny P for not only requesting some examples but also presenting some concrete areas he wasn’t fully clear on. Let’s start by looking at those (and feel free to compare the responses I’ve put below with the ones I made in direct response to Danny’s original comment): Within a transaction where something is added to the database, some new objects... Read more →

Calling Dispose() on AutoCAD objects

This is a follow-on to this previous post, prompted by a thread over on The Swamp discussing a recent blog post by Fenton Webb on the AutoCAD DevBlog. Fenton’s assertion is that you really need to call Dispose() on all AutoCAD objects that you create yourself, unless they are managed by AutoCAD’s transaction system (i.e. you’ve passed responsibility across to AutoCAD by calling Transaction.AddNewlyCreatedDBObject()). Which means that while you don’t need to call Dispose() on objects such as the AutoCAD Editor or the active Document (and you really shouldn’t), you really should call Dispose() on various objects you’ve been... Read more →

Creating 3D street art using AutoCAD

As mentioned in this previous post, I was very keen to see how AutoCAD could be used to help streamline the process of generating what I’ve now found out can be classified as anamorphic street art. Leon Keer had mentioned that the technique dates back to Leonardo Da Vinci and – sure enough – Wikipedia agrees. As part of my research, I found the original video that inspired my interest in Leon’s work, which should help put this post in context: To make the process reasonably realistic – and to some degree replicate the approach Leon has taken in... Read more →

Sphere packing in AutoCAD: filling an arbitrary solid using .NET

As we’re nearing the end of this series, it seems a good time to do a quick recap of where we’ve been with the posts leading up to this point. Here goes… An interesting challenge: generating variable density fill patterns for 3D printing Generating hyperbolic geometry on a Poincaré disk in AutoCAD using .NET Generating hyperbolic tessellations inside AutoCAD using .NET Scripting the generation of hyperbolic tessellations inside AutoCAD Circle packing in AutoCAD: creating an Apollonian gasket using .NET Circle packing in AutoCAD: creating an Apollonian gasket using F# – Part 1 Circle packing in AutoCAD: creating an Apollonian... Read more →

Sphere packing in AutoCAD: creating an Apollonian packing using F# – Part 3

As suggested in the last post, today we’re going to take the results of running the code from that post and use them to generate a hollowed-out sphere. A big thanks to Francesco Tonioni, from our Product Support team in Neuchatel, who spent some time throwing ideas around on a lazy (but very cold) Sunday afternoon, contributing significantly to this post. A few minor changes to the code were needed: rather than creating the spheres at exactly the size at which they were generated by the F# code, I adjusted the C# code to multiply the radius by 0.98... Read more →

Sphere packing in AutoCAD: creating an Apollonian packing using F# – Part 2

This post continues the series on fill algorithms for 3D printing by looking specifically at an Apollonian sphere packing. In the last post we got most of the way there, but today we’re going to introduce a more elegant algorithm for solving the problem (with pretty impressive results :-). Many thanks to Professor Ronald Peikert from ETH Zurich for kindly providing the C++ code used to generate the F# code in today’s post. The original algorithm was outlined in this paper co-authored by Professor Peikert, under the section The “Inversion Algorithm” and – as you might divine from the... Read more →

Sphere packing in AutoCAD: creating an Apollonian packing using F# – Part 1

So far in this series, we’ve looked at Apollonian circle packing using C# and also F#. The next few posts will look at solving this problem in 3D: performing Apollonian sphere packing. I’ve decided to stay in F# for the algorithmic side of things: it just feels a much cleaner environment for dealing with this kind of problem, and, besides, I’ve been having too much fun with it. :-) One thing I should mention, as this series is nominally about 3D printing fill algorithms: printing hollow spheres isn’t at all straightforward with today’s 3D printing technology, as support material... Read more →

Chamfering the selected edge of an AutoCAD solid using .NET

Another piece of code culled from an email from Balaji Ramamoorthy, from DevTech India. I did a little refactoring and formatting, to fit the blog. Thanks, Balaji! :-) The below C# code demonstrates how to use Solid3d.ChamferEdges() with a user-selected edge and face. Balaji has also provided code to determine the edge and face programmatically – without the user needing to select anything – using the Brep API. I expect to show that approach in a subsequent post. using Autodesk.AutoCAD.ApplicationServices; using Autodesk.AutoCAD.DatabaseServices; using Autodesk.AutoCAD.EditorInput; using Autodesk.AutoCAD.Runtime; using System; namespace SolidEditing { public class Commands { [CommandMethod("EC")] public void EdgeChamfer()... Read more →

Adding speech recognition to AutoCAD via Kinect

Oh, what fun. Kinect’s audio capabilities were an area that I hadn’t spent any time on, but an email conversation with a developer (thanks, Glenn! ;-) spurred me to take a closer look. The Beta 2 version of the Microsoft Kinect SDK, there’s a new sample showing how to process audio and add speech recognition via the Microsoft Speech SDK. The Kinect SDK sample is pretty interesting: it displays a graphical indicator of where the sound is located, relative to the device (its array of four microphones allows Kinect to quite accurately position where sound is coming from, presumably... Read more →

Using the Microsoft Kinect SDK to sweep segmented solids inside AutoCAD

This post follows on from this recent post which showed a flat port of the previous OpenNI/NITE code which swept a single solid along a spline path defined by the user being tracked by the Kinect device. As mentioned, the previous approach was ultimately flawed, as adding vertices to our spline path made the whole thing problematic (as the sweep operation became less and less likely to succeed). The updated code adopts a slightly different approach: it creates the solid in segments, creating a new segment whenever there’s an error encountered or when the current segment exceeds a certain... Read more →

Identifying holes in an AutoCAD solid using .NET

A big thanks to Ishwar Nagwani – an old friend, colleague and member of Autodesk Consulting working in our Bangalore office – for kindly providing this code. Ishwar tells me that he has come across many developers struggling to identify holes in 3D solid using its boundary representation (Brep). The code he has provided works on the basis that a hole’s normal is typically facing inwards and will therefore intersect the hole’s axis of symmetry, providing we extend the line representing the normal by the hole’s radius and the line representing the axis of symmetry by the cylinder’s height... Read more →