Scenic-Shop

I just updated my frustum calculator to two javascript versions.  One will calculate the flattened frustum from the radii, the other uses the circumferences of the frustum shape.

I’ve been playing around with learning javascript recently.  I’ve thrown together a fluid power calculator as a “hello world”.  You can find it here: Fluid Power Calculator It’s not pretty, but it works pretty well.  (See what I did there?)  You can download the page and run it locally if you want.

My ultimate goal is to transfer all of my theatre-related excel calculators to javascript powered web pages, so I can access them wherever I happen to be.

Scratch – the scratchpad layer utility for AutoCAD – has been updated to version 1.2!

Download Scratch 1.2 here.

Hard to believe its been over a year since I released an update to Scratch.  This update is kind of a sea change for the program, see the notes below.  On another note, this is the last release I am going to issue; I use it every day, and it hasn’t been an active development project for a while.  I might post a short screencast describing how to use it.  I hope you get as much use out of it as I have.  And be forewarned, I’ve got some really cool stuff I’ve been working on.

Usage:

Note: the ` symbol is a backtick (next to the 1 key)

• command: ` – toggle between scratchpad layer and the current layer
• command: e` – erase scratchpad (menu)
  • option: a – erase everything in scratchpad layer
  • option: p – preview all objects in scratchpad layer
  • option: s – erase only selected objects in scratchpad layer
• command: m` – move selected objects to the scratchpad layer
• command: 1` – jumps to previous layer

Release notes:

• consolidated scratch into one file
• changed CST command to `
• changed EST command to e`
• added options to the erase constructions (e`) command
• added move object(s) to scratch layer command (x`)
• general bugfixes
• general performance refinements and code slimming

I’ve decided to do away with the scenic-shop wiki.  I’ve little patience for cleaning up the spam and junk that kept accumulating.  It was quite the failed experiment in any case; I’m both disappointed and frustrated with the outcome.  This makes two failed attempts at starting up an open forum for technical theatre solutions.  Why the failure?  1) Perhaps writing for a wiki format is too challenging or takes too long; though I would describe very few of the successful stagehands I know as slow – so that’s probably not the reason.  2) Perhaps folks don’t want to publish technical solutions without a byline to claim credit.  3) Maybe we’re much more secretive and feudal than I thought.  4) Maybe our free time should be spent drinking beer and eating nachos.  Whatever the reason, there’s still the stagecraft mailing list, yale tech shorts (see what I did there?), Google Groups and the Technical Director’s forum.

I hope I don’t sound bitter, that’s not what I’m going for at all.  I’m still convinced that there’s a way to implement a community driven reference site, I just don’t know what shape it will take.

Peace out.

Did you know you can precisely rotate the current view of modelspace?  This is a killer way to simplify drafting and dimensioning objects on an angle, especially if you have a way to align the current view to an object.  (And we do, keep reading.)

The longhand command is Dview > Dviewblock > Twist.  Enter the angle you want to twist the current view to, and you’re set.  Why type that out every time?  This lisp will do that and more – just type “TW” to invoke.

Download it here.

Command : TW

• Enter the twist angle explicitly (e.g. 45 or -134.25) or…

• Align: set twist angle by picking two points (Point 1 is 0,0 and Point 2 is positive x-axis vector)
• Relative: set twist angle relative to current twist angle
• After twisting the view, the list will prompt yes(default)/no to realign the UCS to the current angle.

Right now the script only does the twist in modelspace, I’m planning on expanding it to work in paperspace & viewports as well.  When I get some free time that is.

Until next time – keep it lazy.

I just realized I never posted those grand piano cad blocks I promised months ago.  You can snag them here (version 2k).  Egg. face. mine.

While I’m at it – this is a link to some commonly used steel profile blocks.  Some of them are dynamic, so you’ll need a newer (2006? I’m too lazy to look it up right now) version of autocad to utilize them.  Inside you’ll find:

• Common (small) rectangular tubing (d-d-d-d-dynamic!)
• Angle Iron (dynamic)
• 1 5/8″ Unistrut
• 280 Track
• Iron Pipe (dynamic)
• 2×4 metal stud

For the three people who keep up with this blog, you’ve probably noticed that I haven’t updated at all in the past several months.  Sorry about that – I’ve recently taken an engineering gig for Production Resource Group‘s scene shop, which includes confidentiality agreements and such.  At this point I’m not sure what is and isn’t considered a trade secret, so I’m holding off on posting any solutions derived from work.  Its a shame, I’ve always been of the mind that information should be free, especially in the theatre.  Ah the price we pay for growing up and moving on to bigger things.  This blog will continue, but it will probably shift even more to AutoCAD related scripts and such.  Now that I’m working at a different shop I’ve been drafting different stuff, and have a boatload of new ideas.  I’ve already started work on several routines; they’ll be up when they’re fit for public consumption.

Good news, I recently added some anti-spam measures to the Stagecraft Wiki, and as a result have re-enabled anonymous editing.  This means you don’t need to login to share your brilliant ideas!  (Hint, hint)

I’ve also added a few more pages.  Our upcoming show has a grand piano, so I’ve thrown some research up at piano dimensions.  I’ll add some cad blocks for the various sizes in a bit.

Also metal tube gauges, cord locks, arboron, and low tack adhesives.

Here we give out excel formulas to do math with architectural measurements (e.g. 14′-3″).

I recently had to calculate the total area of our soft goods inventory.  With over 80 drapes, that’s a lot of number crunching.  Luckily our inventory is in an excel file, which includes the height and width of each drape.  Okay, make a formula to calculate the square area from those values… Problem: the measurements are given in feet and inches (e.g. 12′-1″).  Excel treats this as a string, hence it cannot use it to do math.  Solution: the following formula will strip out the excess characters and convert the measurement to inches — success!

Formula #1

Convert a 13′-10″ style format into inches.  (Replace instances of C3 with the cell containing the measurement to convert.)
=(LEFT(C3,(SEARCH("'",C3,1)-1))*12)+(SUBSTITUTE(SUBSTITUTE((RIGHT(C3,((SEARCH("-",C3,1)) -1))),"-",""),"""","")))

Formula #2

Calculate area from two cells (C3 & D3) from a [feet]‘-[inches]” style format.  Returns area as square feet.

=(((LEFT(C3,(SEARCH("'",C3,1)-1))*12)+(SUBSTITUTE(SUBSTITUTE((RIGHT(C3,((SEARCH("-",C3,1)) -1))),"-",""),"""","")))*((LEFT(D3,(SEARCH("'",D3,1)-1))*12)+(SUBSTITUTE(SUBSTITUTE((RIGHT(D3,((SEARCH("-",D3,1)) -1))),"-",""),"""",""))))/144

The only requirement is that the format must be as follows: 5′-3″
These formulas rely on this format to find the numbers. Perhaps when I find more time, I’ll update them to work with a few different styles.

This AutoCAD lisp command transparently saves the current layerstate.  Subsequent invocations switch between the saved state and the current state.  You can go back and forth until your eyes pop out.

Download and enjoy!

command: LSS
- on first run, it will save a layerstate and exit the command
- option: Previous – (default option), saves the current layerstate and switches you to the original saved layerstate.
- option: Update   – saves the current layerstate for future retrieval.
- option: Clear    – delete the auto-generated layerstates that this script creates.
- option: eXit     – duh.