performLayout method

void performLayout(ChantContext ctxt)

Implementation

void performLayout(ChantContext ctxt) {
  var glyphCode = note.glyphVisualizer!.glyphCode;
  // we have to place the ictus further from the note in some cases to avoid a collision with an episema on the same note:
  var currentPositionHint = positionHint != MarkingPositionHint.defaultHint
      ? positionHint
      : MarkingPositionHint.below;

  var staffPosition =
      note.staffPosition +
      (currentPositionHint == MarkingPositionHint.above ? 1 : -1);

  var collisionWithEpisema =
      note.episemata.isNotEmpty &&
      (note.episemata[0].positionHint != MarkingPositionHint.defaultHint
              ? note.episemata[0].positionHint
              : MarkingPositionHint.above) ==
          currentPositionHint;

  double horizontalOffset;
  double verticalOffset = 1;
  double shortOffset = -0.2;
  double extraOffset = 0;

  var collisionWithStaffLine =
      (staffPosition % 2 != 0) &&
      ((ctxt.convertStaffPositionToSymmetric(staffPosition).abs() <
              ctxt.staffLineCount) ||
          (note.neume!.ledgerLines.isNotEmpty &&
              note.neume!.ledgerLines.first.staffPosition == staffPosition));

  // The porrectus requires special handling of the note width,
  // otherwise the width is just that of the note itself
  if (glyphCode == GlyphCode.porrectus1 ||
      glyphCode == GlyphCode.porrectus2 ||
      glyphCode == GlyphCode.porrectus3 ||
      glyphCode == GlyphCode.porrectus4) {
    horizontalOffset = ctxt.staffInterval / 2;
  } else if (glyphCode == GlyphCode.none) {
    horizontalOffset = -ctxt.staffInterval / 2;
  } else {
    horizontalOffset = note.bounds.width / 2;
    if (glyphCode == GlyphCode.punctumInclinatum &&
        !collisionWithStaffLine &&
        !collisionWithEpisema) {
      extraOffset = 0.3;
    }
  }

  if (positionHint == MarkingPositionHint.above) {
    glyphCode = GlyphCode.verticalEpisemaAbove;
    verticalOffset *= -1;
  } else {
    glyphCode = GlyphCode.verticalEpisemaBelow;
  }

  if (collisionWithEpisema) {
    extraOffset = 0.4;
  }

  verticalOffset *=
      ctxt.staffInterval *
      (extraOffset + (collisionWithStaffLine ? 0.3 : shortOffset));

  setGlyph(ctxt, glyphCode);
  setStaffPosition(ctxt, staffPosition);

  bounds = bounds.copyWith(
    x: note.bounds.x + horizontalOffset - origin.x,
    y: bounds.y + verticalOffset,
  );
}