LEDCircle

class bibliopixel.LEDCircle

LEDCircle provides methods to control pixels arranged in concentric circles. It inherits from LEDBase and provides all of its public methods and properties. LEDCircle actually lives at bibliopixel.led.LEDStrip but can be accessed at bibiliopixel.LEDCircle for convenience.

Unlike LEDStrip or LEDMatrix, the pixels on a circular display are not accessed by index or (x,y) coordinate. Instead, a polar coordinate system is used. While it may seem odd at first, it's much easy to specify the pixels by:

• Ring: Index of the concentric ring on the circle. The center point (or smallest ring) is index 0 and the indices count up from there to the outer-most ring.

• Angle: 0-359 value of the angle on the circle. Negative values are allowed.

Currently, the only known commercial LED display that is arranged like this is one sold by Adafruit. As you can see in the datasheet, the LEDs are, in fact, arranged in concentric circles and not a spiral. This code will not work with a spiral as you must specify the number of pixels in each ring.

One other use for this, for example, would be on a Christmas tree display. As long as care is taken to arrange the pixels in parallel rings, increasing in size down the tree, it should work quite nicely.

__init__

(driver, rings, rotation, maxAngleDiff=0, threadedUpdate=False, masterBrightness=255)

• driver - A driver class or list of driver classes that inherit from bibliopixel.drivers.DriverBase. See the Drivers page for more info.
• rings - Array of first and last pixel index in each ring. For example, the ring mapping for the Adafruit display mentioned above is:

rings = [
    [254,254],  #0 - Center point
    [248,253],  #1
    [236,247],  #2
    [216,235],  #3
    [192,215],  #4
    [164,191],  #5
    [132,163],  #6
    [92,131],   #7
    [48,91],    #8
    [0,47],     #9 - Outer most ring
] 

• maxAngleDiff - Maximum angle the resolved pixel can be from the given angle. If outside of that range (in either direction) the pixel will be dropped. Setting to 0 (default) means to limit.
• rotation - Degrees (-359 through 359) to rotate entire display by.
• threadedUpdate - Display updates will run in background thread if True. Defaults to False.
• masterBrightness - Default master brightness value, 0-255

angleToPixel

(angle, ring)

• angle - Angle (0-359) of pixel on the circle. Nearest pixel to that angle, rounded down, will be chosen.
• ring - Index of the ring on which the pixel lies.

Returns pixel index of nearest pixel to (angle, ring). Should not generally be used.

set

(ring, angle, color)

• ring - Index of the ring on which the pixel lies.
• angle - Angle (0-359) of pixel on the circle. Nearest pixel to that angle, rounded down, will be chosen.
• color - RGB tuple, (r,g,b), representing the color to set.

Set value of pixel at (angle, ring) to given color.

get

(ring, angle)

• ring - Index of the ring on which the pixel lies.
• angle - Angle (0-359) of pixel on the circle. Nearest pixel to that angle, rounded down, will be chosen.

Returns RGB tuple, (r,g,b), if pixel is in bounds. Otherwise returns (0,0,0).

drawRadius

(angle, color, startRing, endRing)

• angle - Angle (0-359) of pixel on the circle. Nearest pixel to that angle, rounded down, will be chosen.
• color - RGB tuple, (r,g,b), representing the color to draw.
• startRing - Index of the ring where the line should start.
• endRing - Index of the ring where the line should stop. Defaults to lastRing.

Draws a line along a given angle from startRing to endRing, in the given color

fillRing

(ring, color, startAngle, endAngle)

• ring - Index of ring to fill.
• color - RGB tuple, (r,g,b), representing the color to fill.
• startAngle - Angle where the fill should start.
• endAngle - Angle where the fill should stop. Defaults to 359.

Fills (draws and arc) along a given ring with the given color.

Properties

---

rings

Array of the ring mapping provided init method.

ringCount

Total number of rings.

lastRing

Index of the outer most ring on the circle.

ringSteps

Array of degrees between each pixel for the given ring index.