OpenDrop - Inverted Text Renderer

text.pde

import processing.serial.*;
import static javax.swing.JOptionPane.*;

Serial myPort;

// Configurable params          
// i.e.: final String  displayText    = "Hello World   ";
final String  displayText    = "AaBbCcDdEeFfGgHhIiJjKkLlMmNnOoPpQqRrSsTtUuVvWwXxYyZz";
final int     scrollInterval = 200;
final boolean WARN_RESERVOIR = true;
final boolean UI_MODE        = true;

// Grid dimensions
final int GRID_WIDTH   = 14;
final int GRID_HEIGHT  = 8;
final int WINDOW_WIDTH = 700;
final int WINDOW_HEIGHT= 400;

// Electrode state
boolean[][] electrodes = new boolean[GRID_WIDTH][GRID_HEIGHT];

// Scrolling text state
int       lastScrollTime;
int       scrollOffset;       // current column index into buffer
int       charHeight     = 7; // 6 + extra bottom line 
int[][][] fontMap;            // fontMap[char] → 3×6 pattern

void setup() {
  noLoop();  // delay draw until after setup
  windowResize(WINDOW_WIDTH, WINDOW_HEIGHT);

  // —— serial init ——
  String[] ports = Serial.list();
  if (ports == null || ports.length == 0) {
    showMessageDialog(null,
      "No serial ports found. Connect your device and retry.",
      "Serial Port Error", ERROR_MESSAGE);
    exit();
  }
  myPort = new Serial(this, ports[0], 115200);
  delay(100);

  // —— initial board fill ——  
  initialTransmit();
  if (WARN_RESERVOIR) showMessageDialog(null,
    "Fill the board (except reservoir) with liquid *now*, then press OK.",
    "Initial setup", PLAIN_MESSAGE);

  // —— text font setup ——
  buildFontMap();

  // —— start scrolling ——  
  lastScrollTime = millis();
  scrollOffset    = 0;

  // —— kickoff ——  
  if (UI_MODE) windowResize(WINDOW_WIDTH, WINDOW_HEIGHT);
  frameRate(60);
  loop();
}

void draw() {
  if (millis() - lastScrollTime > scrollInterval) {
    scrollOffset = (scrollOffset + 1) % totalColumns();
    lastScrollTime = millis();
  }

  // render into electrodes then send + draw
  drawBoard();
  transmit();
  if (UI_MODE) renderGrid();
}

// ————————————— text rendering —————————————————

void drawBoard() {
  // clear all ON
  for (int x = 0; x < GRID_WIDTH; x++)
    for (int y = 0; y < GRID_HEIGHT; y++)
      electrodes[x][y] = true;

  int cols = totalColumns();
  for (int gx = 0; gx < GRID_WIDTH; gx++) {
    int bufCol = (scrollOffset + gx) % cols;

    // walk through displayText to find which char this column belongs to
    int  running   = 0;
    char c         = 0;
    int  colInChar = -1;
    for (int i = 0; i < displayText.length(); i++) {
      char tc = displayText.charAt(i);
      int idx = (int)tc;
      int[][] charData = fontMap[idx];
      if (charData != null) {
        int w = charData.length;
        if (bufCol < running + w) {
          c = tc;
          colInChar = bufCol - running;
          break;
        }
        running += w;
      }
      // one‐column spacing
      if (bufCol < running + 1) {
        c = 0;
        break;
      }
      running += 1;
    }

    // if it’s part of a real character, render its pixels
    if (c != 0 && colInChar >= 0) {
      int idx = (int)c;
      int[][] charData = fontMap[idx];
      if (charData != null && colInChar < charData.length) {
        for (int row = 0; row < charHeight; row++) {
          boolean on = (charData[colInChar][row] == 1);
          int gy = row + (GRID_HEIGHT - charHeight)/2 + 1;
          electrodes[gx][gy] = !on;
        }
      }
    }
  }
}

int totalColumns() {
  int sum = 0;
  for (int i = 0; i < displayText.length(); i++) {
    int idx = (int)displayText.charAt(i);
    if (fontMap[idx] != null) {
      sum += fontMap[idx].length;  // character width
    }
    sum += 1;  // spacing
  }
  return sum;
}

// ————————————— serial I/O —————————————————

void initialTransmit() {
  for (int x = 0; x < GRID_WIDTH;  x++)
    for (int y = 0; y < GRID_HEIGHT; y++)
      electrodes[x][y] = true;

  byte[] packet = new byte[32];
  packet[0] = 0;
  for (int x = 0; x < GRID_WIDTH; x++) {
    int b = 0;
    for (int y = 0; y < GRID_HEIGHT; y++)
      if (electrodes[x][y])
        b |= 1<<y;
    packet[x+1] = (byte)b;
  }
  packet[GRID_WIDTH+1] = 0;
  for (byte pb : packet) myPort.write(pb);
}

void transmit() {
  byte[] packet = new byte[32];
  packet[0] = (byte)0xFF;
  for (int x = 0; x < GRID_WIDTH; x++) {
    int b = 0;
    for (int y = 0; y < GRID_HEIGHT; y++)
      if (electrodes[x][y])
        b |= 1<<y;
    packet[x+1] = (byte)b;
  }
  packet[GRID_WIDTH+1] = (byte)0xFF;
  for (byte pb : packet) myPort.write(pb);
}

// ————————————— UI rendering —————————————————

void renderGrid() {
  int cellW = width  / GRID_WIDTH;
  int cellH = height / GRID_HEIGHT;
  stroke(80);
  for (int x = 0; x < GRID_WIDTH; x++) {
    for (int y = 0; y < GRID_HEIGHT; y++) {
      fill(electrodes[x][y] ? color(0,200,0) : 50);
      rect(x*cellW, y*cellH, cellW-2, cellH-2);
    }
  }
}

// ————————————— font definition —————————————————

void buildFontMap() {
  fontMap = new int[128][][];

  fontMap['A'] = new int[][] {
    {0,1,1,1,1,1,0},
    {1,0,0,1,0,0,0},
    {0,1,1,1,1,1,0}
  };
  
  fontMap['a'] = new int[][] {
    {0,0,1,0,1,1,0},
    {0,0,1,0,1,1,0},
    {0,0,0,1,1,1,0}
  };

  fontMap['B'] = new int[][] {
    {1,1,1,1,1,1,0},
    {1,0,1,1,0,1,0},
    {0,1,0,0,1,1,0}
  };
  
  fontMap['b'] = new int[][] {
    {0,1,1,1,1,1,0},
    {0,0,0,1,0,1,0},
    {0,0,0,0,1,0,0}
  };
  
  fontMap['C'] = new int[][] {
    {0,1,1,1,1,0,0},
    {1,0,0,0,0,1,0},
    {1,0,0,0,0,1,0}
  };
  
  fontMap['c'] = new int[][] {
    {0,0,0,1,1,0,0},
    {0,0,1,0,0,1,0},
    {0,0,1,0,0,1,0}
  };
  
  fontMap['D'] = new int[][] {
    {1,1,1,1,1,1,0},
    {1,0,0,0,0,1,0},
    {0,1,1,1,1,0,0}
  };
  
  fontMap['d'] = new int[][] {
    {0,0,0,0,1,0,0},
    {0,0,0,1,0,1,0},
    {0,1,1,1,1,1,0}
  };
  
  fontMap['E'] = new int[][] {
    {1,1,1,1,1,1,0},
    {1,0,1,0,0,1,0},
    {1,0,1,0,0,1,0}
  };
  
  fontMap['e'] = new int[][] {
    {0,0,1,1,1,1,0},
    {0,0,1,1,0,1,0},
    {0,0,1,0,0,1,0}
  };
  
  fontMap['F'] = new int[][] {
    {1,1,1,1,1,1,0},
    {1,0,1,0,0,0,0},
    {1,0,1,0,0,0,0}
  };
  
  fontMap['f'] = new int[][] {
    {0,0,1,1,1,1,0},
    {0,1,0,1,0,0,0},
    {0,1,0,0,0,0,0}
  };
  
  fontMap['G'] = new int[][] {
    {0,1,1,1,1,1,0},
    {1,0,0,0,0,1,0},
    {1,0,0,1,1,1,0}
  };
  
  fontMap['g'] = new int[][] {
    {0,0,0,1,1,0,1},
    {0,0,1,0,1,0,1},
    {0,0,0,1,1,1,1}
  };
  
  fontMap['H'] = new int[][] {
    {1,1,1,1,1,1,0},
    {0,0,1,1,0,0,0},
    {1,1,1,1,1,1,0}
  };
  
  fontMap['h'] = new int[][] {
    {0,1,1,1,1,1,0},
    {0,0,0,1,0,0,0},
    {0,0,0,0,1,1,0}
  };
  
  fontMap['I'] = new int[][] {
    {1,0,0,0,0,1,0},
    {1,1,1,1,1,1,0},
    {1,0,0,0,0,1,0}
  };
  
  fontMap['i'] = new int[][] {
    {0,1,0,1,1,1,0},
  };
  
  fontMap['J'] = new int[][] {
    {0,0,0,0,1,0,0},
    {0,0,0,0,0,1,0},
    {1,1,1,1,1,0,0}
  };
  
  fontMap['j'] = new int[][] {
    {0,0,0,0,0,1,0},
    {0,0,0,0,0,0,1},
    {0,1,0,1,1,1,0}
  };
  
  fontMap['K'] = new int[][] {
    {1,1,1,1,1,1,0},
    {0,0,1,1,0,0,0},
    {1,1,0,0,1,1,0}
  };
  
  fontMap['k'] = new int[][] {
    {0,1,1,1,1,1,0},
    {0,0,0,0,1,0,0},
    {0,0,0,1,0,1,0}
  };
  
  fontMap['L'] = new int[][] {
    {1,1,1,1,1,1,0},
    {0,0,0,0,0,1,0},
    {0,0,0,0,0,1,0}
  };
  
  fontMap['l'] = new int[][] {
    {0,1,1,1,1,1,0},
  };
  
  fontMap['M'] = new int[][] {
    {1,1,1,1,1,1,0},
    {0,1,0,0,0,0,0},
    {0,0,1,1,0,0,0},
    {0,1,0,0,0,0,0},
    {1,1,1,1,1,1,0}
  };
  
  fontMap['m'] = new int[][] {
    {0,0,1,1,1,1,0},
    {0,0,1,0,0,0,0},
    {0,0,0,1,1,1,0},
    {0,0,1,0,0,0,0},
    {0,0,0,1,1,1,0}
  };
  
  fontMap['N'] = new int[][] {
    {1,1,1,1,1,1,0},
    {0,1,1,0,0,0,0},
    {0,0,0,1,1,0,0},
    {1,1,1,1,1,1,0}
  };
  
  fontMap['n'] = new int[][] {
    {0,0,1,1,1,1,0},
    {0,0,1,0,0,0,0},
    {0,0,0,1,1,1,0}
  };
  
  fontMap['O'] = new int[][] {
    {0,1,1,1,1,0,0},
    {1,0,0,0,0,1,0},
    {0,1,1,1,1,0,0}
  };
  
  fontMap['o'] = new int[][] {
    {0,0,0,1,1,0,0},
    {0,0,1,0,0,1,0},
    {0,0,0,1,1,0,0}
  };
  
  fontMap['P'] = new int[][] {
    {1,1,1,1,1,1,0},
    {1,0,1,0,0,0,0},
    {0,1,0,0,0,0,0}
  };
  
  fontMap['p'] = new int[][] {
    {0,0,1,1,1,1,1},
    {0,0,1,0,1,0,0},
    {0,0,0,1,0,0,0}
  };
  
  fontMap['Q'] = new int[][] {
    {0,1,1,1,1,0,0},
    {1,0,0,0,0,1,0},
    {0,1,1,1,1,0,1}
  };
  
  fontMap['q'] = new int[][] {
    {0,0,0,1,0,0,0},
    {0,0,1,0,1,0,0},
    {0,0,1,1,1,1,1}
  };
  
  fontMap['R'] = new int[][] {
    {1,1,1,1,1,1,0},
    {1,0,1,0,0,0,0},
    {0,1,0,1,1,1,0}
  };
  
  fontMap['r'] = new int[][] {
    {0,0,1,1,1,1,0},
    {0,0,0,1,0,0,0},
    {0,0,1,0,0,0,0}
  };
  
  fontMap['S'] = new int[][] {
    {0,1,1,0,0,1,0},
    {1,0,0,1,0,1,0},
    {0,1,0,0,1,0,0}
  };
  
  fontMap['s'] = new int[][] {
    {0,0,1,1,0,1,0},
    {0,0,1,1,0,1,0},
    {0,0,1,0,1,1,0},
    {0,0,1,0,1,1,0}
  };
  
  fontMap['T'] = new int[][] {
    {1,0,0,0,0,0,0},
    {1,1,1,1,1,1,0},
    {1,0,0,0,0,0,0}
  };
  
  fontMap['t'] = new int[][] {
    {0,1,1,1,1,0,0},
    {0,0,1,0,0,1,0},
    {0,0,0,0,0,1,0}
  };
  
  fontMap['U'] = new int[][] {
    {1,1,1,1,1,1,0},
    {0,0,0,0,0,1,0},
    {1,1,1,1,1,1,0}
  };
  
  fontMap['u'] = new int[][] {
    {0,0,1,1,1,1,0},
    {0,0,0,0,0,1,0},
    {0,0,1,1,1,1,0}
  };
  
  fontMap['V'] = new int[][] {
    {1,1,1,1,1,0,0},
    {0,0,0,0,0,1,0},
    {1,1,1,1,1,0,0}
  };
  
  fontMap['v'] = new int[][] {
    {0,0,1,1,1,0,0},
    {0,0,0,0,0,1,0},
    {0,0,1,1,1,0,0}
  };
  
  fontMap['W'] = new int[][] {
    {1,1,1,1,1,0,0},
    {0,0,0,0,0,1,0},
    {0,0,0,1,1,0,0},
    {0,0,0,0,0,1,0},
    {1,1,1,1,1,0,0}
  };
  
  fontMap['w'] = new int[][] {
    {0,0,1,1,1,0,0},
    {0,0,0,0,0,1,0},
    {0,0,0,1,1,0,0},
    {0,0,0,0,0,1,0},
    {0,0,1,1,1,0,0}
  };
  
  fontMap['X'] = new int[][] {
    {1,1,0,0,1,1,0},
    {0,0,1,1,0,0,0},
    {1,1,0,0,1,1,0}
  };
  
  fontMap['x'] = new int[][] {
    {0,0,1,0,0,1,0},
    {0,0,0,1,1,0,0},
    {0,0,1,0,0,1,0}
  };
  
  fontMap['Y'] = new int[][] {
    {1,1,1,0,0,0,0},
    {0,0,0,1,1,1,0},
    {1,1,1,0,0,0,0}
  };
  
  fontMap['y'] = new int[][] {
    {0,0,1,1,0,0,1},
    {0,0,0,0,1,1,0},
    {0,0,1,1,0,0,0}
  };
  
  fontMap['Z'] = new int[][] {
    {1,0,0,0,1,1,0},
    {1,0,1,1,0,1,0},
    {1,1,0,0,0,1,0}
  };
  
  fontMap['z'] = new int[][] {
    {0,0,1,0,0,1,0},
    {0,0,1,0,1,1,0},
    {0,0,1,1,0,1,0},
    {0,0,1,0,0,1,0}
  };
  
  fontMap[' '] = new int[][] {
    {0,0,0,0,0,0,0},
  };
}