diff --git a/examples/circuitplayground_acceleration_mapping_neopixels.py b/examples/circuitplayground_acceleration_mapping_neopixels.py new file mode 100644 index 0000000..597eb31 --- /dev/null +++ b/examples/circuitplayground_acceleration_mapping_neopixels.py @@ -0,0 +1,48 @@ +"""Maps acceleration (tilt) to Neopixel colors. + +x, y, and z acceleration components map to red, green and blue, +respectively. + +When the CPX is level, the lights are blue because there is no acceleration +on x or y, but on z, gravity pulls at 9.81 meters per second per second (m/s²). +When banking, the vertical (z) axis is no longer directly aligned with gravity, +so the blue decreases, and red increases because gravity is now pulling more +along the x axis. Similarly, when changing the pitch from level, we see blue change +to green. + +This video walks you through the code: https://youtu.be/eNpPLbYx-iA +""" + +import time +from adafruit_circuitplayground.express import cpx + +cpx.pixels.brightness = 0.2 # Adjust overall brightness as desired, between 0 and 1 + + +def color_amount(accel_component): + """Convert acceleration component (x, y, or z) to color amount (r, g, or b)""" + standard_gravity = 9.81 # Acceleration (m/s²) due to gravity at the earth’s surface + accel_magnitude = abs(accel_component) # Ignore the direction + constrained_accel = min(accel_magnitude, standard_gravity) # Constrain values + normalized_accel = constrained_accel / standard_gravity # Convert to 0–1 + return round(normalized_accel * 255) # Convert to 0–255 + + +def format_acceleration(): + return ', '.join(('{:>6.2f}'.format(axis_value) for axis_value in acceleration)) + + +def format_rgb(): + return ', '.join(('{:>3d}'.format(rgb_amount) for rgb_amount in rgb_amounts)) + + +def log_values(): + print('({}) ==> ({})'.format(format_acceleration(), format_rgb())) + + +while True: + acceleration = cpx.acceleration + rgb_amounts = [color_amount(axis_value) for axis_value in acceleration] + cpx.pixels.fill(rgb_amounts) + log_values() + time.sleep(0.1)