Tuesday, October 27, 2009

Progress Report #1 - The Block Diagram Cleanup Experiment

As I mentioned a few months ago, I am attempting to use Block Diagram Cleanup for 100% of my diagram arrangement needs in LabVIEW 2009. I figured I might post updates every once in a while detailing my progress. So here, in no particular order, are some of my observations and impressions after heavy use of block diagram cleanup for a few months:
  • It Creates Big Diagrams - When left to my own devices, I create tight diagrams with very little whitespace. I have very quickly discovered that diagram cleanup is rather liberal with its allocation of whitespace. :) Typically this is because I've got a moderately nested diagram, and diagram cleanup doesn't quite know how to allocate space in each frame of a multiframe structure such that whitespace is minimized. I imagine this would be a rather difficult problem to solve, since it would require the repositioning algorithm to simultaneously keep track of the spacing in each frame of a multiframe structure.
  • It Doesn't Respect My Window Size - Along similar lines, the diagram gets resized and often goes past the height and/or width of the diagram window. Sometimes I have diagram windows set to a particular size for a reason, and if I were arranging the diagram myself, I would fit the diagram within those window bounds. I wish we could constrain diagram cleanup to the current diagram's window bounds.
  • It Creates Bendy Wires - I've always been very careful to minimize the number of bends in my wires, maybe because my boss was always very picky about it. In fact, he's the one who insisted "Wire Bends" be a test that shipped with VI Analyzer 1.0! Anyway, diagram cleanup doesn't seem to be so concerned about wire bends. From what little I know about the cleanup algorithm, this makes sense because the algorithm is very much concerned with node placement, and not so much wire placement (except for its strict insistence on keeping error wires straight, which I like). But if you've got nodes that you've arranged just to keep non-error wires straight, diagram cleanup will not take this into account when rearranging. Also, if you've got constants wired to things, and you've got the constants positioned to minimize wire bends, I frequently see the constant moved, and wires bent as a result.
  • It Moves My Control Terminal Labels - I like my control terminals on the sides (left for controls, right for indicators)...in fact, I added the Ctrl-Space-Ctrl-T shortcut in LabVIEW 2009 to make it easier to perform this operation in bulk for all top-level terminals on the diagram. But I've noticed my terminal labels get moved by cleanup, and it doesn't look like something that's configurable.
  • But...I Code Faster - Despite its shortcomings, block diagram cleanup allows me to code *much* faster than I do when arranging the diagram myself. I don't have any specifics, but I'd estimate that I write VIs about twice as fast as normal when I spend zero time arranging diagram objects myself.
These are my first impressions of block diagram cleanup, with just a few months of LabVIEW 2009 development (on a mishmash of small projects). But right now, I'm in the beginning stages of writing a LabVIEW Class-based prototype for a LabVIEW Scripting architecture for my current project. I hope to post more detailed observations as I become more involved in this adventure.

Friday, October 16, 2009

Quick Drop Keyboard Shortcut - Commands for "Create" Menu Options

My third post-release Quick Drop keyboard shortcut is now available on the NI Community website. This shortcut allows you to perform all the options in the right-click > Create... menu with your keyboard. You can perform these operations with one or more objects selected. For example, you could select several control terminals on the diagram, press Ctrl-Space, type reference, and press Ctrl-A, and a control reference will be created for each one, just as if you had right-clicked them individually and selected Create > Reference on each one. Check it out and let me know what you think:

Quick Drop Keyboard Shortcut - Commands for "Create" Menu Options

Friday, October 9, 2009

Quick Drop Keyboard Shortcut - Create Object from Terminal

My second post-release Quick Drop keyboard shortcut is now available on the NI Community website. This shortcut allows you to perform the Create Control/Indicator/Constant action on a terminal without having to navigate the right-click menus, simply by pressing the shortcut keys while hovering your mouse over the terminal. You can also optionally use the Quick Drop combo box to type the value of a constant created in this manner. Check it out and let me know what you think:


Note: This shortcut works on Windows and Linux, but not Mac.