Through the Interface

AutoCAD I/O v2

The AutoCAD I/O team has deployed version 2 of their API. For specific information on what’s new, check this page. As I’ll be talking about AutoCAD I/O at AU 2015, I thought it important to get to grips with the new version and understand how it differs from v1. I went ahead and updated Jigsawify.com to make use of the new API, so I’ll add my own commentary below on the changes that have been introduced. As a reminder, the full source code for Jigsawify.com is available on GitHub. To check out the specific migration changes, see this comparison... Read more →

Detecting and erasing zero-length lines in an AutoCAD drawing using .NET

A question came in by email, yesterday, and despite having a few mini-projects in progress that were spawned during last week’s event in Prague, I couldn’t resist putting some code together to address it. The developer wanted to purge zero-length geometry: the simplest way to solve the problem is to run “_-PURGE _Z” at the command-line, but I saw this more as an opportunity to create a simple helper that would loop through all the entities in a drawing and erase any meeting a specified condition. In this case it would be curves with a length less than the... Read more →

Creating an AutoCAD palette dynamically to launch commands and methods tagged using .NET

I needed to run some code from a modeless dialog, the other day, and found it was a bit of a pain to generate something quickly to do so. So I thought it might be a good idea to populate a palette dynamically with buttons that call commands and methods that were somehow tagged in the current project. The first step was to work out how to tag them: the obvious choice being some kind of method-level designation (much as we have with the CommandMethod() attribute). I created a command – named PC, for PaletteCommands – that uses reflection... Read more →

Launching AutoCAD’s REFEDIT command with an entity selected using .NET

A really interesting problem came up during an internal discussion, this week: someone wanted to launch the REFEDIT command on a selected xref and pre-select the entity found at the picked point. The entity that’s part of the selected xref, of course. This turned out to be quite a tricky problem and yet one that could be solved with relatively few lines of code. The tricky parts were finding the right entity in the nested selection and then the corresponding entity in the xref. Here’s the approach I ended up taking: Ask the user to selected a nested entity... Read more →

Passing large amounts of data to an AutoCAD I/O activity

I mentioned recently that I’d hit a limitation with the amount of data that could be passed as embedded JSON data to an AutoCAD I/O Activity, and so decided to rearchitect my site to post the data at a URL and have the Activity download and use the data from there. The system worked well until a security flaw was fixed by the AutoCAD I/O team, earlier this week: it turns out the approach of manually downloading the additional payload from the Activity itself wasn’t supposed to work. And now, sure enough, it doesn’t. :-) This video does a... Read more →

Passing AutoCAD objects to commands called via .NET

This question came in as a blog comment on this previous post: Is possible to use Revision Cloud in this situation? Example: Creating a polyline/circle/ellipse then make it a revision cloud. It seemed to make sense to broaden the topic for the purposes of this blog post: how to pass an entity or entities to an AutoCAD command called via Editor.Command() or CommandAsync(). Since Editor.Command() was implemented in AutoCAD 2015, I’ve been a fan of the calling commands in AutoCAD application code. But I haven’t actually covered the approach needed to send object information to commands via this function.... Read more →

Preventing an AutoCAD block from being exploded using .NET (redux)

When I was a boy, I used to love going to play with toys at my grandmother’s house. My absolute favourite was a die-cast Batmobile made by Corgi in the UK. What I particularly liked about this toy was its hidden features: the cars apparently came with secret instructions, although these were nowhere to be seen by the time I started playing with it. The Batmobile had plastic flames that came out of the exhaust when the rear wheels turned and spring-loadable, vertical rocket launchers. The biggest surprise was when I discovered the cutting blade that popped out of... Read more →

Creating a rectangular jigsaw puzzle with specific dimensions inside AutoCAD using .NET

Following on from the last post, where we saw an outline for this series of posts on AutoCAD I/O, today’s post adds a command to our jigsaw application that creates the geometry for a jigsaw puzzle of a specified size and with a specified number of pieces. As jigsaw puzzle pieces are largely quite square, it actually took me some time to get my head around the mathematics needed to calculate the number of pieces we need in each of the X and Y directions to make a puzzle of a certain size. And it’s (with hindsight) obviously not... Read more →

AutoCAD I/O and custom applications

The title of this post is probably a bit misleading: I’m not actually going to show how this works, today, but I do intend to plot a path for addressing this topic over the coming weeks. I was spurred on by a tweet I received a couple of hours ago: @keanw Dear kean, I've been looking into AutoCAD I/O and it looks like it may only execute "scripts"; so no .NET API calls or LISP? — Cyborg (@CyborgEvilHam) May 13, 2015 The short answer to this is “yes, it’s absolutely possible!”. But readers of this blog are clearly interested... Read more →

Autodesk University 2015 class proposals

A reminder that proposals are open for AU2015 until May 26th. I’ve just submitted two, myself. Of the three topics I had in mind – relating to VR, AutoCAD I/O and TypeScript – I decided to submit proposals on the first two: I’ll do my best to use TypeScript for one or both of the other two (assuming they get accepted) which will at least give people some exposure to how the technology works. And give some good fodder for blog posts, of course. Here are the abstracts I submitted: Virtual Reality viewing of 3D models using Autodesk's View... Read more →

Invoking AutoCAD’s UI Finder from JavaScript

On my flight back from Singapore I started thinking about how an app might help people discover what’s new in the AutoCAD UI from release to release. This might also work for custom functionality, but that’s not (currently) my main concern. I was thinking of displaying some kind of palette that cycles through the new commands and features in a release, highlighting the associated ribbon buttons, etc., using the AutoCAD help system’s excellent UI Finder capability. Over the weekend I started looking at how it might work – whether it was possible to call the UI Finder from an... Read more →

AutoCAD 2016: Calling commands from external events using .NET

Last week we introduced the ExecuteInCommandContextAsync() method and saw it in action from a context menu click event. In today’s post we’re going to see how it can be used for a lot more: we’re going to use it to respond to external, operating system-level events (although admittedly we’re handling the event in-process to AutoCAD via .NET). What we’re actually going to do is fire off a command inside AutoCAD – in our case we’re going to use RECTANG to create square polylines – each time we find that a file has been placed in a particular folder (in... Read more →

AutoCAD 2016: Calling commands from AutoCAD events using .NET

It’s time to start looking in more detail at some of the new API capabilities in AutoCAD 2016. To give you a sense of what to expect in terms of a timeline, this week we’ll look at a couple of uses for DocumentCollection.ExecuteInCommandContextAsync() and next week we’ll look at point cloud floorplan extraction and (hopefully) security and signing. The first use of ExecuteInCommandContextAsync() I wanted to highlight was one raised in a blog comment a couple of months ago. The idea is simple enough: we want to be able to launch a command reliably from an event handler, in... Read more →

AutoCAD 2016 for developers

After our quick look at AutoCAD 2016 from a user perspective, let’s now spend some time looking at the things important to developers in this latest release. Compatibility Off the bat it’s worth stating that AutoCAD 2016 is a DWG compatible release: it’s using the same file format as AutoCAD 2013, 2014 and 2015. It’s also a binary application compatible release: ObjectARX apps written for AutoCAD 2015 should work in 2016 and it’s likely that .NET apps built for AutoCAD 2014 will work, too. That said, some changes have been made to the security model for this release of... Read more →

Docking a WPF window inside AutoCAD – Part 3

In this post we’re wrapping up this mini-series on docking, which is part of a much broader story arc around a “command-line helper” tool, of course. But then we’re reaching the end of that, too, I suspect, as the app’s just about done. Hopefully it’s ready for posting to Autodesk Labs, at least. Last time we added right-click dragging to allow our keywords window to be moved around without interrupting the active command. Now we’re taking it a step further to preview docking at one of the four corners of the drawing window, as well as to actually dock... Read more →

Docking a WPF window inside AutoCAD – Part 2

I’m happy to say that the implementation I mentioned in the last post ended up being pretty straightforward. Which is actually great, as I have some important posts to work on for next week. :-) Today we’re going to take a look at the next stage of the “command-line helper” implementation: basic right-click movement of the global keywords dialog, so we can set a custom location for the dialog without needing to use the KWSDOCK command. Here’s the code in action: The main work for this stage was to add support for right-click, mouse move and right mouse-button up... Read more →

Adding support for global keywords at AutoCAD’s command-line using .NET – Part 2

Today we’re going to look at the implementation talked about in the last post: we’re going to see how it’s possible to use the Application.PreTranslateMessage() method to hack AutoCAD’s message-loop and basically convert typed keywords into global ones. This is actually pretty neat (yes, even if I do say so myself :-) and frankly I’m surprised it works. Here’s the overall approach: Track the characters typed into the command-line Add individual characters into a list Backspace removes the tail of the list Arrow-keys invalidate the tracking: if the user accesses entries in the command-history we can’t deal with that,... Read more →

Adding support for global keywords at AutoCAD’s command-line using .NET – Part 1

This post carries on from this series from a couple of weeks ago: Adding a global keyword menu to AutoCAD using WPF – Part 1 Adding a global keyword menu to AutoCAD using WPF – Part 2 Enabling global commands on localized AutoCAD versions using .NET The overall goal behind these posts was to create a “command-line helper” tool to make it easier for people who know the English version of AutoCAD (or an AutoCAD-based vertical) to work with a corresponding localized version. Basically because some people learn AutoCAD using an English version – perhaps during their studies –... Read more →

Enabling global commands on localized AutoCAD versions using .NET

Here’s a quick piece of code to finish up the week to complement what we saw earlier. The idea is that on localized AutoCAD versions this code will allow the user to enter English commands without needing the underscore prefix. The code works by detecting an “unknown” command and then attempting to execute it again after prefixing an underscore to launch a global command. Which may or may not work, of course, so we certainly need to set a flag to avoid descending into an infinite loop of commands being called while prefixed by an ever-expanding legion of underscores.... Read more →

Adding a global keyword menu to AutoCAD using WPF – Part 2

After introducing this project in the last post, now it’s time to share some code. The project, as it currently stands, contains three source files: the first one relates to AutoCAD – it implements the various commands we’ll use to attach event handlers to tell us when to display (or hide) keywords and the other two files relate to the UI we’ll use to display them. We’re going to use an invisible window which has a child popup containing a listbox of our keywords. Here’s the application in action – for now in English AutoCAD, as that’s what I... Read more →