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Preset Desk

This is a simple preset lighting desk that I wrote to help me learn some of the basics of using the cocoa AppKit. I will probably be extending the functionality of this desk as I build features I need for my main lighting application. Once I have those basics done, and know a bit more about AppKit I will be in a position to start on the real application.

As always please feel free to with any comments or suggestions you might have regarding this application.

You can either connect the USB DMX interface before or after starting the preset desk application, however you should not disconnect it untill you have closed the desk.

Preset Desk Screen

The desk has 3 modes of operation (A/B, Wide and Sub Master Memory). You select the current operating mode by clicking the B Bank Mode button on the bottom right of the desk.

A/B (Preset) Mode

This is the classic simple preset mode. The top faders (A Bank) and bottom faders (B Bank) both operate the same 24 channels (DMX Channels 1 - 24). You can either move the fader by clicking on it and dragging (this will continuously change the light level output), or by clicking the desired fader level. For precise setting you can enter a number between 0 and 255 in the box below an A, B or the master fader.

To cross-fade between the A and B Banks use the fader located to the left of the Grand Master. For a smooth timed cross-fade, simply click the 'auto' button at the end of the cross-fade fader. You can change the cross-fade time by entering a new time in seconds in the box just beyond the 'Auto' button.

Wide Mode

This mode turns the desk into a simple 48 channel desk. The A Bank faders control channels 1 - 24, whilst the B Bank faders control channel 25 - 48.

Sub Master Memory Mode

This turns the B Bank faders into 24 sub masters, each controlling 24 channels, allowing up-to 24 scenes to be dynamically mixed and cross-faded.

To store a scene set the A Bank faders to the desired level (this either done live in 'A/B' or 'Wide' mode so you can see the levels, or done in 'Sub Master' mode without affecting the current output). Then select the scene memory, either by entering a number, or using the clicker at the top right of the desk. Press 'Save' to save the A Bank faders to the scene memory, or Load to load the selected scene memory into the the A Bank faders.

The B Bank faders will then act as a sub master for the corresponding scene memory. Selecting 'Faders track output' makes the A Bank Faders track the main DMX output. This can be useful if you wish to save the current output of several mixed scenes into a new one. If you wish to slightly adjust the output, turn the tracking mode off, make your changes and then save to a new scene.

Dimmer curves

You can customise the DMX output for each channel, by applying a dimmer curve. This allows you to add pre-heat for example, or correct the curve on a dimmer that you are not happy with. To show the editor select "Dimmer Curve" -> "Show Curve" from the menu bar.

The curve editor will automaticaly switch to the channel of any fader you update.

There are 3 types of curves, Linear, Single and Double. The Linear curves are good for adding pre-heat, or capping the overall output of a channel, whilst a single and double curve type allow you to set the curve with 1 or 2 control points respectivly.

To change the curve simply move the mouse over a control point (including the start and end of the curve) it will change when your mouse is over it. Then click and drag it to the desired location.

Customised Dimmer Curves Panel


The preset desk application is supplied without any warranty, explicit or implied, and I accept no responsibility for the corruption or loss of any data, and / or hardware caused by the use, or installation, of this application.

You may not reverse engineer, decompile or disassemble the application, except and only to the extent that such activity is expressly permitted by applicable law notwithstanding this limitation.

You may not sell, rent, lease, sub-lease or incorporate the whole or any part of the use of the application in any other program or system without express written agreement.

preset_desk.dmg (124KB)