Hi,

I have a problem in drawing line.

Code :
    vertices = vertices.concat([0, 0, 0]);
    vertices = vertices.concat([0, 0, 2]);
    vertices = vertices.concat([2, 0, 0]);
    vertices = vertices.concat([3, 0, 1]);
    vertices = vertices.concat([1, 2, 1]);
 
    geometryVertexIndices = geometryVertexIndices.concat([0, 1, 1, 2, 2, 0, 1, 2, 2, 3, 3, 1]);
    unpackedColors = unpackedColors.concat(color);
    unpackedColors = unpackedColors.concat(color);
    unpackedColors = unpackedColors.concat(color);
    unpackedColors = unpackedColors.concat(color);
    unpackedColors = unpackedColors.concat(color);

In this coding, I can draw two triangles successfully in Chrome (use the first four vertices). However, when I change the Index to the following (add one more line [1, 4]):

Code :
geometryVertexIndices = geometryVertexIndices.concat([0, 1, 1, 2, 2, 0, 1, 2, 2, 3, 3, 1, 1, 4]);

It cannot draw triangles and shows nothing in the Chrome. If I change to the following (using the last vertice):

Code :
geometryVertexIndices = geometryVertexIndices.concat([0, 1, 1, 2, 2, 0, 1, 2, 2, 3, 3, 4]);

It also shows nothing in the Chrome. I think WebGL cannot draw anything because I use the fifth vertice. May I know how to solve this problem?