elbear_arduino_bsp/libraries/NeoPixel/src/NeoPixel.cpp

#include "NeoPixel.h"

NeoPixel::NeoPixel(uint16_t n, int16_t p, neoPixelType t)
    : begun(false), brightness(0), pixels(NULL), endTime(0) {
  updateType(t);
  updateLength(n);
  setPin(p);
}

NeoPixel::NeoPixel()
    : is800KHz(true), begun(false), numLEDs(0), numBytes(0), pin(-1), brightness(0),
      pixels(NULL), rOffset(1), gOffset(0), bOffset(2), wOffset(1), endTime(0) {
}

NeoPixel::~NeoPixel() {
  free(pixels);
  if (pin >= 0)
    pinMode(pin, INPUT);
}

void NeoPixel::begin(void) {
  if (pin >= 0) {
    pinMode(pin, OUTPUT);
    digitalWrite(pin, LOW);
  }
  begun = true;
}

void NeoPixel::updateLength(uint16_t n) {
  free(pixels); // Free existing data (if any)

  // Allocate new data -- note: ALL PIXELS ARE CLEARED
  numBytes = n * ((wOffset == rOffset) ? 3 : 4);
  if ((pixels = (uint8_t *)malloc(numBytes))) {
    memset(pixels, 0, numBytes);
    numLEDs = n;
  } else {
    numLEDs = numBytes = 0;
  }
}

void NeoPixel::updateType(neoPixelType t) {
  bool oldThreeBytesPerPixel = (wOffset == rOffset); // false if RGBW

  wOffset = (t >> 6) & 0b11; // See notes in header file
  rOffset = (t >> 4) & 0b11; // regarding R/G/B/W offsets
  gOffset = (t >> 2) & 0b11;
  bOffset = t & 0b11;
  is800KHz = (t < 256); // 400 KHz flag is 1<<8

  if (pixels) {
    bool newThreeBytesPerPixel = (wOffset == rOffset);
    if (newThreeBytesPerPixel != oldThreeBytesPerPixel)
      updateLength(numLEDs);
  }
}

static void __attribute__((noinline, section(".ram_text"))) mik32Show(GPIO_TypeDef* m_port, uint32_t m_pin, uint8_t* pixels, uint32_t numBytes, bool is800KHz) {
  // not support 400khz
  if (!is800KHz) return;

  volatile uint32_t* set = &m_port->SET;
  volatile uint32_t* clr = &m_port->CLEAR;

  uint8_t* ptr = pixels;
  uint8_t* end = ptr + numBytes;
  uint8_t p = *ptr++;
  uint8_t bitMask = 0x80;
 
  noInterrupts();
  
  while (1) {
    if (p & bitMask) { // ONE
      // High 800ns - 25,6 tick
      *set = m_pin;
      __asm volatile (
        "nop; nop; nop; nop; nop; nop; nop; nop;"
        "nop; nop; nop; nop; nop; nop; nop; nop;"
        "nop; nop; nop; nop;"
      );

      // Low 450ns - 14,4 tick
      *clr = m_pin;
      __asm volatile (
        "nop; nop; nop; nop; nop;"
      );
    } else {   // ZERO
      // High 400ns - 12,8 tick
      *set = m_pin;
      __asm volatile (
        "nop; nop; nop; nop; nop; nop;"
      );

      // Low 850ns - 27,2 tick
      *clr = m_pin;
      __asm volatile (
        "nop; nop; nop; nop; nop; nop; nop; nop;"
        "nop; nop; nop;"
      );
    }

    if (bitMask >>= 1) {
      // Move on to the next pixel
    }
    else {
      if (ptr >= end) {
        break;
      }
      p = *ptr++;
      bitMask = 0x80;
    }
  }
  interrupts();
}

void NeoPixel::show(void) {

  if (!pixels)
    return;

  while (!canShow())
    ;
  mik32Show(gpioPort, gpioPin, pixels, numBytes, is800KHz);
  endTime = micros(); // Save EOD time for latch on next call
}

void NeoPixel::setPin(int16_t p) {
  if (begun && (pin >= 0))
    pinMode(pin, INPUT); // Disable existing out pin
  pin = p;
  if (begun) {
    pinMode(p, OUTPUT);
    digitalWrite(p, LOW);
  }
  
  gpioPort = digitalPinToPort(pin);
  gpioPin = digitalPinToBitMask(pin);
}

void NeoPixel::setPixelColor(uint16_t n, uint8_t r, uint8_t g,
                                      uint8_t b) {
  if (n < numLEDs) {
    if (brightness) { // See notes in setBrightness()
      r = (r * brightness) >> 8;
      g = (g * brightness) >> 8;
      b = (b * brightness) >> 8;
    }
    uint8_t *p;
    if (wOffset == rOffset) { // Is an RGB-type strip
      p = &pixels[n * 3];     // 3 bytes per pixel
    } else {                  // Is a WRGB-type strip
      p = &pixels[n * 4];     // 4 bytes per pixel
      p[wOffset] = 0;         // But only R,G,B passed -- set W to 0
    }
    p[rOffset] = r; // R,G,B always stored
    p[gOffset] = g;
    p[bOffset] = b;
  }
}

void NeoPixel::setPixelColor(uint16_t n, uint8_t r, uint8_t g,
                                      uint8_t b, uint8_t w) {

  if (n < numLEDs) {
    if (brightness) { // See notes in setBrightness()
      r = (r * brightness) >> 8;
      g = (g * brightness) >> 8;
      b = (b * brightness) >> 8;
      w = (w * brightness) >> 8;
    }
    uint8_t *p;
    if (wOffset == rOffset) { // Is an RGB-type strip
      p = &pixels[n * 3];     // 3 bytes per pixel (ignore W)
    } else {                  // Is a WRGB-type strip
      p = &pixels[n * 4];     // 4 bytes per pixel
      p[wOffset] = w;         // Store W
    }
    p[rOffset] = r; // Store R,G,B
    p[gOffset] = g;
    p[bOffset] = b;
  }
}

void NeoPixel::setPixelColor(uint16_t n, uint32_t c) {
  if (n < numLEDs) {
    uint8_t *p, r = (uint8_t)(c >> 16), g = (uint8_t)(c >> 8), b = (uint8_t)c;
    if (brightness) { // See notes in setBrightness()
      r = (r * brightness) >> 8;
      g = (g * brightness) >> 8;
      b = (b * brightness) >> 8;
    }
    if (wOffset == rOffset) {
      p = &pixels[n * 3];
    } else {
      p = &pixels[n * 4];
      uint8_t w = (uint8_t)(c >> 24);
      p[wOffset] = brightness ? ((w * brightness) >> 8) : w;
    }
    p[rOffset] = r;
    p[gOffset] = g;
    p[bOffset] = b;
  }
}

void NeoPixel::fill(uint32_t c, uint16_t first, uint16_t count) {
  uint16_t i, end;

  if (first >= numLEDs) {
    return; // If first LED is past end of strip, nothing to do
  }

  // Calculate the index ONE AFTER the last pixel to fill
  if (count == 0) {
    // Fill to end of strip
    end = numLEDs;
  } else {
    // Ensure that the loop won't go past the last pixel
    end = first + count;
    if (end > numLEDs)
      end = numLEDs;
  }

  for (i = first; i < end; i++) {
    this->setPixelColor(i, c);
  }
}

uint32_t NeoPixel::ColorHSV(uint16_t hue, uint8_t sat, uint8_t val) {

  uint8_t r, g, b;
  
  hue = (hue * 1530L + 32768) / 65536;
  
  if (hue < 510) { // Red to Green-1
    b = 0;
    if (hue < 255) { //   Red to Yellow-1
      r = 255;
      g = hue;       //     g = 0 to 254
    } else {         //   Yellow to Green-1
      r = 510 - hue; //     r = 255 to 1
      g = 255;
    }
  } else if (hue < 1020) { // Green to Blue-1
    r = 0;
    if (hue < 765) { //   Green to Cyan-1
      g = 255;
      b = hue - 510;  //     b = 0 to 254
    } else {          //   Cyan to Blue-1
      g = 1020 - hue; //     g = 255 to 1
      b = 255;
    }
  } else if (hue < 1530) { // Blue to Red-1
    g = 0;
    if (hue < 1275) { //   Blue to Magenta-1
      r = hue - 1020; //     r = 0 to 254
      b = 255;
    } else { //   Magenta to Red-1
      r = 255;
      b = 1530 - hue; //     b = 255 to 1
    }
  } else { // Last 0.5 Red (quicker than % operator)
    r = 255;
    g = b = 0;
  }

  // Apply saturation and value to R,G,B, pack into 32-bit result:
  uint32_t v1 = 1 + val;  // 1 to 256; allows >>8 instead of /255
  uint16_t s1 = 1 + sat;  // 1 to 256; same reason
  uint8_t s2 = 255 - sat; // 255 to 0
  return ((((((r * s1) >> 8) + s2) * v1) & 0xff00) << 8) |
         (((((g * s1) >> 8) + s2) * v1) & 0xff00) |
         (((((b * s1) >> 8) + s2) * v1) >> 8);
}


uint32_t NeoPixel::getPixelColor(uint16_t n) const {
  if (n >= numLEDs)
    return 0; // Out of bounds, return no color.

  uint8_t *p;

  if (wOffset == rOffset) { // Is RGB-type device
    p = &pixels[n * 3];
    if (brightness) {
      
      return (((uint32_t)(p[rOffset] << 8) / brightness) << 16) |
             (((uint32_t)(p[gOffset] << 8) / brightness) << 8) |
             ((uint32_t)(p[bOffset] << 8) / brightness);
    } else {
      // No brightness adjustment has been made -- return 'raw' color
      return ((uint32_t)p[rOffset] << 16) | ((uint32_t)p[gOffset] << 8) |
             (uint32_t)p[bOffset];
    }
  } else { // Is RGBW-type device
    p = &pixels[n * 4];
    if (brightness) { // Return scaled color
      return (((uint32_t)(p[wOffset] << 8) / brightness) << 24) |
             (((uint32_t)(p[rOffset] << 8) / brightness) << 16) |
             (((uint32_t)(p[gOffset] << 8) / brightness) << 8) |
             ((uint32_t)(p[bOffset] << 8) / brightness);
    } else { // Return raw color
      return ((uint32_t)p[wOffset] << 24) | ((uint32_t)p[rOffset] << 16) |
             ((uint32_t)p[gOffset] << 8) | (uint32_t)p[bOffset];
    }
  }
}

void NeoPixel::setBrightness(uint8_t b) {
  
  uint8_t newBrightness = b + 1;
  if (newBrightness != brightness) { 
    
    uint8_t c, *ptr = pixels,
               oldBrightness = brightness - 1; // De-wrap old brightness value
    uint16_t scale;
    if (oldBrightness == 0)
      scale = 0; // Avoid /0
    else if (b == 255)
      scale = 65535 / oldBrightness;
    else
      scale = (((uint16_t)newBrightness << 8) - 1) / oldBrightness;
    for (uint16_t i = 0; i < numBytes; i++) {
      c = *ptr;
      *ptr++ = (c * scale) >> 8;
    }
    brightness = newBrightness;
  }
}

uint8_t NeoPixel::getBrightness(void) const { return brightness - 1; }

void NeoPixel::clear(void) { memset(pixels, 0, numBytes); }

uint32_t NeoPixel::gamma32(uint32_t x) {
  uint8_t *y = (uint8_t *)&x;
  
  for (uint8_t i = 0; i < 4; i++)
    y[i] = gamma8(y[i]);
  return x; // Packed 32-bit return
}

void NeoPixel::rainbow(uint16_t first_hue, int8_t reps,
  uint8_t saturation, uint8_t brightness, bool gammify) {
  for (uint16_t i=0; i<numLEDs; i++) {
    uint16_t hue = first_hue + (i * reps * 65536) / numLEDs;
    uint32_t color = ColorHSV(hue, saturation, brightness);
    if (gammify) color = gamma32(color);
    setPixelColor(i, color);
  }
}

neoPixelType NeoPixel::str2order(const char *v) {
  int8_t r = 0, g = 0, b = 0, w = -1;
  if (v) {
    char c;
    for (uint8_t i=0; ((c = tolower(v[i]))); i++) {
      if (c == 'r') r = i;
      else if (c == 'g') g = i;
      else if (c == 'b') b = i;
      else if (c == 'w') w = i;
    }
    r &= 3;
  }
  if (w < 0) w = r; // If 'w' not specified, duplicate r bits
  return (w << 6) | (r << 4) | ((g & 3) << 2) | (b & 3);
}