buildPath method

Path? buildPath(String inputData)

Implementation

Path? buildPath(String inputData) {
  Path p = Path();
  try {
    var matcher = _svgInstructionPattern.allMatches(inputData).toList();

    var lastX = 0.0;
    var lastY = 0.0;
    var lastX1 = 0.0;
    var lastY1 = 0.0;
    var subPathStartX = 0.0;
    var subPathStartY = 0.0;
    var curve = false;

    matcher.forEach((matchElem) {
      var command = matchElem.group(1)!;
      var coordinateStr = matchElem.group(2)!;
      // print("[$command]: $coordinateStr");

      switch (command.toLowerCase()) {
        case 'm':
          var it = coordinateStr.split(',');
          var x = double.parse(it[0]);
          var y = double.parse(it[1]);

          // Check if command is uppercase:
          if (command == command.toUpperCase()) {
            subPathStartX = x;
            subPathStartY = y;
            p.moveTo(x, y);
            lastX = x;
            lastY = y;
          } else {
            subPathStartX += x;
            subPathStartY += y;
            p.moveTo(x, y);
            lastX += x;
            lastY += y;
          }
          break;
        case 'l':
          var it = coordinateStr.split(',');
          var x = double.parse(it[0]);
          var y = double.parse(it[1]);
          if (command == command.toUpperCase()) {
            p.lineTo(x, y);
            lastX = x;
            lastY = y;
          } else {
            p.relativeLineTo(x, y);
            lastX += x;
            lastY += y;
          }
          break;
        case 'v':
          List<double> coordinates = getCoordinatesGroup(coordinateStr);
          var y = coordinates.first;
          if (command == command.toUpperCase()) {
            p.lineTo(lastX, y);
            lastY = y;
          } else {
            p.relativeLineTo(0.0, y);
            lastY += y;
          }
          break;
        case 'h':
          List<double> coordinates = getCoordinatesGroup(coordinateStr);
          var x = coordinates.first;
          if (command == command.toUpperCase()) {
            p.lineTo(x, lastY);
            lastX = x;
          } else {
            p.relativeLineTo(x, 0.0);
            lastX += x;
          }
          break;
        case 'c':
          curve = true;
          List<double> coordinates = getCoordinatesGroup(coordinateStr);
          var x1 = coordinates[0];
          var y1 = coordinates[1];

          var x2 = coordinates[2];
          var y2 = coordinates[3];

          var x = coordinates[4];
          var y = coordinates[5];

          if (command == command.toLowerCase()) {
            x1 += lastX;
            x2 += lastX;
            x += lastX;
            y1 += lastY;
            y2 += lastY;
            y += lastY;
          }

          p.cubicTo(x1, y1, x2, y2, x, y);

          lastX1 = x2;
          lastY1 = y2;
          lastX = x;
          lastY = y;

          break;
        case 's':
          curve = true;
          List<double> coordinates = getCoordinatesGroup(coordinateStr);
          var x2 = coordinates[0];
          var y2 = coordinates[1];

          var x = coordinates[2];
          var y = coordinates[3];

          if (command == command.toLowerCase()) {
            x2 += lastX;
            x += lastX;
            y2 += lastY;
            y += lastY;
          }

          var x1 = 2 * lastX - lastX1;
          var y1 = 2 * lastY - lastY1;

          p.cubicTo(x1, y1, x2, y2, x, y);
          lastX1 = x2;
          lastY1 = y2;
          lastX = x;
          lastY = y;

          break;
        case 'z':
          p.close();
          p.moveTo(subPathStartX, subPathStartY);
          lastX = subPathStartX;
          lastY = subPathStartY;
          lastX1 = subPathStartX;
          lastY1 = subPathStartY;
          break;
        default:
          throw Error();
      }
    });

    if (!curve) {
      lastX1 = lastX;
      lastY1 = lastY;
    }

    return p;
  } catch (_) {
    return null;
  }
}