Add NeoPixel program for a fading strip.

1 files changed, 38 insertions, 0 deletions

diff --git a/strip/strip.ino b/strip/strip.ino
new file mode 100644
index 0000000..ce9edf8
--- /dev/null
+++ b/strip/strip.ino
@@ -0,0 +1,38 @@
+#include <Adafruit_NeoPixel.h>
+
+#include <Adafruit_NeoPixel.h>
+
+#define PIN 7
+#define NUM_LEDS 16
+
+Adafruit_NeoPixel strip = Adafruit_NeoPixel(NUM_LEDS, PIN, NEO_GRB + NEO_KHZ800);
+// Adafruit_NeoPixel strip = Adafruit_NeoPixel(60, PIN, NEO_RGBW + NEO_KHZ800);
+
+void setup() {
+  strip.begin();
+  strip.show(); // Initialize all pixels to 'off'
+}
+
+int32_t g = 0;
+
+// Gets the intensity for LED `l`.
+// s is a step between 0 and 1000.
+// l is the led number, between 0 and NUM_LEDS.
+float grad(int s, int l, float num_pixels) {
+  float scaled = s * 16.0 / 1000;
+  float distance = abs(scaled - l);
+  float val = 1 - (2/num_pixels) * distance;
+  return max(0, val);
+}
+
+void loop() {
+  float num_pixels = 2.8;
+  for (int i = 0; i < 1000; i++) {
+    for (int pixel = 0; pixel < 16; pixel++) {
+      // strip.setPixelColor(pixel, 0, 5, 50);
+      strip.setPixelColor(pixel, strip.Color(0, 0, grad(i, pixel, num_pixels) * 255));
+    }
+    strip.show();
+    delay(1);
+  }
+}