LED light question for newbie

#include <Adafruit_NeoPixel.h>

#define PIN 13
#define KEYPIN 2

Adafruit_NeoPixel horse = Adafruit_NeoPixel(64, PIN, NEO_GRB + NEO_KHZ800);

uint32_t horseCount,lastRead,flashCount;
uint8_t key,previous;

void setup() {
  Serial.begin(115200);
  horseCount=0xfc000000;  //0b11111100000000000000000000000000;
  horse.begin();
  horse.show();
  pinMode(KEYPIN,INPUT_PULLUP);
  lastRead=0;
  displayHorse();
}

void loop(){
  if((millis()-lastRead)>20){       //read key every 20mS
    lastRead=millis();
    key=digitalRead(KEYPIN);
    if(key==0 && previous==1){
      progressHorse();              //move horse along
      displayHorse();               //update the display
      flashCount=millis();          //just to ensure the flash starts lit
    }
    previous=key;                   //keep a copy for next read
  }
  if(horseCount==0xfffffffc){       //all 30 LEDs lit?
    if((millis()-flashCount)>50){   //flash the display at 10Hz
      clearDisplay();
    }
    if((millis()-flashCount)>100){  //the 50 and 100 control the flash rate
      displayHorse();
      flashCount=millis();
    }
  }
}

void progressHorse(){               //move the horse on
  if(horseCount == 0xfffffffc){     //or if completed
    horseCount=0xfc000000;          //reset to first 6 LEDs
    return;
  }
  horseCount>>=1;
  horseCount|=0x80000000;
}

void displayHorse(){
  uint32_t temp=horseCount;
  uint8_t i;
  for(i=0;i<32;i++){
    if(temp&0x80000000)
      horse.setPixelColor(i,horse.Color(25,25,25));
    else
      horse.setPixelColor(i,horse.Color(0,0,0));
    temp<<=1;
  }
  for(i=0;i<32;i++)
    horse.setPixelColor(i+32,horse.Color(0,0,0));
  horse.show();
}

void clearDisplay(){
  uint8_t i;
  for(i=0;i<64;i++)
    horse.setPixelColor(i,horse.Color(0,0,0));
  horse.show();
}