Helios DAC CHOP
Helios DAC is a laser controller. The Helios DAC CHOP takes as input up to five channels interpreted as X and Y (horizontal and vertical) position values in the first 2 channels, and red, green and blue color values in the next 3 channels. It outputs the data to a Helios DAC. The Helios DAC device is connected to a laser using an ILDA cable. The user can then control the image that the laser should output using the Helios DAC CHOP. Applications of the Helios DAC CHOP include displaying computer-generated shape animations or other special effects of a light show.
Blanking (all-off) occurs when the incoming RGB CHOP channels are all zero, or the Red Scale, Green Scale, and Blue Scale parameters are all zero.
Large changes in RGB values from sample-to-sample will likely be visibly correct as lasers generally can switch on-off quickly.
The range of X and Y is typically -1 to +1, and the range of RGB is typically 0 to 1.
Parameters - Helios DAC Page
Active - If turned off, the Helios DAC CHOP will stop sending data to the Helios DAC and will immediately clear its point buffer. Consider it equivalent to powering off the Helios DAC.
Device - Select the Helios DAC you want to control from this menu.
Queue Time - Determines the queue size of the Helios DAC CHOP point buffer and the corresponding time required to drain it. It is often useful to reduce this value when sending fewer points.
X Scale - Allows the input x values to be scaled by the specified factor.
Y Scale - Allows the input y values to be scaled by the specified factor.
Red Scale - Allows the input r values to be scaled by the specified factor.
Green Scale - Allows the input g values to be scaled by the specified factor.
Blue Scale - Allows the input b values to be scaled by the specified factor.
Input 1 - Any CHOP can be connected as an input. The data from the first and second channels of the input CHOP will be interpreted as x.y values respectively, and the data from the third, fourth, and fifth channels will be interpreted as the r.g.b values respectively. Furthermore, the input values should range from
+1 for x.y values and from
+1 for r.g.b values.
It should be noted that the Sample Rate of the connected input will determine the point output rate of the Helios DAC (how fast the points are drawn by the laser). This value is specific for each instance of a generated point, and is not a global modifier.
When working with geometry from SOPs or textures from TOPs, it is often useful to have a Scan CHOP as an input source for the Helios DAC CHOP. This will allow the image to first be converted into data values and then be fed into the Helios DAC CHOP.