@thewtex/vtk.js-esm/Filters/General/ImageMarchingSquares/caseTable.js

Visualization Toolkit for the Web

// ----------------------------------------------------------------------------
// Marching squares case functions (using lines to generate the 2D tessellation).
// For each case, a list of edge ids that form the triangles. A -1 marks the
// end of the list of edges. Edges are taken three at a time to generate
// triangle points.
// ----------------------------------------------------------------------------
var MARCHING_SQUARES_CASES = [[-1, -1, -1, -1, -1]
/* 0 */
, [0, 3, -1, -1, -1]
/* 1 */
, [1, 0, -1, -1, -1]
/* 2 */
, [1, 3, -1, -1, -1]
/* 3 */
, [2, 1, -1, -1, -1]
/* 4 */
, [0, 3, 2, 1, -1]
/* 5 */
, [2, 0, -1, -1, -1]
/* 6 */
, [2, 3, -1, -1, -1]
/* 7 */
, [3, 2, -1, -1, -1]
/* 8 */
, [0, 2, -1, -1, -1]
/* 9 */
, [1, 0, 3, 2, -1]
/* 10 */
, [1, 2, -1, -1, -1]
/* 11 */
, [3, 1, -1, -1, -1]
/* 12 */
, [0, 1, -1, -1, -1]
/* 13 */
, [3, 0, -1, -1, -1]
/* 14 */
, [-1, -1, -1, -1, -1]
/* 15 */
];
var EDGES = [[0, 1], [1, 3], [2, 3], [0, 2]];

function getCase(index) {
  return MARCHING_SQUARES_CASES[index];
} // Define the four edges of the pixel by the following pairs of vertices


function getEdge(eid) {
  return EDGES[eid];
} // ----------------------------------------------------------------------------
// Static API
// ----------------------------------------------------------------------------


var vtkCaseTable = {
  getCase: getCase,
  getEdge: getEdge
};

export default vtkCaseTable;