Ever have trouble showing fancy patterns on LEDs because your layout is chaotic or a zigzag and you can't address the lights easily in order? This code is designed to give you a mapping output that contains the coordinates of each light ready to paste into your arduino pattern code and it does so semi-automatically by using a webcam to detect the position of each light.
The code here is in two parts - the arduino part and the processing part. You need to flash your arduino compatible microcontroller of choice with the arduino part, then connect to it using the (hopefully) platform independent processing sketch.
- FastLED http://fastled.io/
- controlP5 by Andreas Schlegel http://www.sojamo.de/libraries/controlP5
- blobDetection http://www.v3ga.net/processing/BlobDetection/
- processing serial (built in)
- processing video (built in)
- java.util (you should also have this!)
You quite possibly have all but the blobDetection library already. There are lots of tutorials available elsewhere if you need assistance with installing libraries but it should be very simple with the new library managers.
You will need the above libraries installed and you need to have a webcam for the processing side (at the moment, there will be other options in the future) then you are ready to start.
- Edit the arduino code LEDmap.ino to suit your LED type, number and pins, refer to fastLED docs if you have trouble with this part
- The LEDs should start flashing orange to indicate controller is ready and waiting
- Connect PC/laptop with serial cable
- Run the processing code LEDmap.pde
- Select your webcam and the controllers serial port from the drop-downs
- Use the 'showall leds' button and the threshold and brightness sliders to make sure it's detecting blobs around all lights
- Press automap and it will start to generate a mapping, it will stop automatically when finished
- Select an output and save as a text file
- The text file now contains code to paste into your own code that has the LED mappings in a style as mentioned in more detail below.
Currently there's one useable output style when you save the mapping - outputting byte values (0-255) for each coordinate in the format:
For convenience saving the output creates a line for copy and pasting with the NUM_LEDS so an example output is:
#define NUM_LEDS 20
struct map2d mapping ={
{248,249,249,248,252,237,233,234,233,233,211,212,212,212,215,187,185,184,184,184},
{73,100,127,157,182,183,155,128,101,73,72,100,127,154,182,179,151,123,96,68}
};
You will need the following defined to make use of the pasted mapping:
struct map2d {
byte x[NUM_LEDS];
byte y[NUM_LEDS];
};
It's small, it's simple and it's easy to address the coords of an LED by using for example
int xcoord = mapping.x[position];
int ycoord = mapping.y[position];
See the included "Examples" folder for examples of useage using fastLED, as you can see it takes very little code to make complex patterns that work on any layout of pixels spread over an area.
The map coordinates are 0,0 in the top left, 255,255 in the bottom right.
If you are reading this just now stay tuned for more documentation and proper 1.0 release when I'm a bit happier with how useful it is but it should be useable right now. This is a completely rewritten from scratch version of my old unwieldy hacky code, it lacks a huge number of features which I will hopefully be adding in soon, see 'issues' for some of them.