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// modified: May 10, 2018
// 
// testshapes demo for RGBmatrixPanel library.
// Demonstrates the drawing abilities of the RGBmatrixPanel library.
// For 32x64 RGB LED matrix.

// NOTE THIS CAN ONLY BE USED ON A MEGA! NOT ENOUGH RAM ON UNO!

#include <Adafruit_GFX.h>   // Core graphics library
#include <RGBmatrixPanel.h> // Hardware-specific library

#define CLK 11
#define LAT 10
#define OE   9
#define A   A0
#define B   A1
#define C   A2
#define D   A3

RGBmatrixPanel matrix(A, B, C, D, CLK, LAT, OE, false, 64);

void setup() {

  matrix.begin();

  // draw a pixel in solid white
  matrix.drawPixel(0, 0, matrix.Color333(7, 7, 7));
  delay(500);

  // fix the screen with green
  matrix.fillRect(0, 0, matrix.width(), matrix.height(), matrix.Color333(0, 7, 0));
  delay(500);

  // draw a box in yellow
  matrix.drawRect(0, 0, matrix.width(), matrix.height(), matrix.Color333(7, 7, 0));
  delay(500);

  // draw an 'X' in red
  matrix.drawLine(0, 0, matrix.width() - 1, matrix.height() - 1, matrix.Color333(7, 0, 0));
  matrix.drawLine(matrix.width() - 1, 0, 0, matrix.height() - 1, matrix.Color333(7, 0, 0));
  delay(500);

  // draw a blue circle
  matrix.drawCircle(10, 10, 10, matrix.Color333(0, 0, 7));
  delay(500);

  // fill a violet circle
  matrix.fillCircle(40, 21, 10, matrix.Color333(7, 0, 7));
  delay(500);

  // fill the screen with 'black'
  matrix.fillScreen(matrix.Color333(0, 0, 0));

  // draw some text!
  matrix.setTextSize(1);     // size 1 == 8 pixels high
  matrix.setTextWrap(false); // Don't wrap at end of line - will do ourselves

  matrix.setCursor(8, 0);    // start at top left, with 8 pixel of spacing
  uint8_t w = 0;
  char *str = "SparkFun";
  for (w = 0; w < 8; w++) {
    matrix.setTextColor(Wheel(w));
    matrix.print(str[w]);
  }
  matrix.setCursor(2, 8);    // next line
  matrix.print(' ');
  matrix.print(' ');
  matrix.setTextColor(matrix.Color333(7, 0, 7));
  matrix.print('H');
  matrix.setTextColor(matrix.Color333(6, 0, 6));
  matrix.print('I');
  matrix.setTextColor(matrix.Color333(4, 0, 0));
  matrix.print(' ');
  matrix.setTextColor(matrix.Color333(6, 0, 5));
  matrix.print('M');
  matrix.setTextColor(matrix.Color333(5, 0, 5));
  matrix.print('O');
  //matrix.setCursor(34, 24);
  matrix.setTextColor(matrix.Color333(4, 0, 4));
  matrix.print("M");
  matrix.setTextColor(matrix.Color333(4, 4, 4));
  matrix.print('!');

  matrix.println();
  matrix.setTextColor(matrix.Color333(7, 0, 0));
  matrix.print('L');
  matrix.setTextColor(matrix.Color333(7, 4, 0));
  matrix.print('E');
  matrix.setTextColor(matrix.Color333(7, 7, 0));
  matrix.print('D');
  matrix.setTextColor(matrix.Color333(4, 7, 0));
  matrix.print(' ');
  matrix.setTextColor(matrix.Color333(0, 7, 0));
  matrix.print('M');
  //matrix.setCursor(34, 24);
  matrix.setTextColor(matrix.Color333(0, 7, 7));
  matrix.print("A");
  matrix.setTextColor(matrix.Color333(0, 4, 7));
  matrix.print('T');
  matrix.setTextColor(matrix.Color333(0, 0, 7));
  matrix.print('R');
  matrix.setTextColor(matrix.Color333(4, 0, 7));
  matrix.print("I");
  matrix.setTextColor(matrix.Color333(7, 0, 4));
  matrix.println("X");

  // print each letter with a rainbow color
  matrix.setTextColor(matrix.Color333(7, 7, 7));
  matrix.print('3');
  matrix.setTextColor(matrix.Color333(7, 7, 7));
  matrix.print('2');
  matrix.setTextColor(matrix.Color333(7, 7, 7));
  matrix.print('x');
  matrix.setTextColor(matrix.Color333(7, 7, 7));
  matrix.print('6');
  matrix.setTextColor(matrix.Color333(7, 7, 7));
  matrix.print('4');
  matrix.setCursor(34, 24);
  matrix.setTextColor(matrix.Color333(0, 7, 7));
  matrix.print("*");
  matrix.setTextColor(matrix.Color333(7, 0, 0));
  matrix.print('R');
  matrix.setTextColor(matrix.Color333(0, 7, 0));
  matrix.print('G');
  matrix.setTextColor(matrix.Color333(0, 0, 7));
  matrix.print("B");
  matrix.setTextColor(matrix.Color333(0, 7, 7));
  matrix.println("*");
  
  // whew!
}

void loop() {
  // do nothing
}


// Input a value 0 to 24 to get a color value.
// The colours are a transition r - g - b - back to r.
uint16_t Wheel(byte WheelPos) {
  if (WheelPos < 8) {
    return matrix.Color333(7 - WheelPos, WheelPos, 0);
  } else if (WheelPos < 16) {
    WheelPos -= 8;
    return matrix.Color333(0, 7 - WheelPos, WheelPos);
  } else {
    WheelPos -= 16;
    return matrix.Color333(0, WheelPos, 7 - WheelPos);
  }
}