Physics and Terrains - WebGL Game Development - page 240

The following code copies the generated UV coordinates to the uvs array of the
Geometry class at the index 0. It is the index of the first material. Also our geometry
will use only one material:
uvs[0].push(uva[0]);
uvs[0].push(uva[1]);
uvs[0].push(uvb[0]);
uvs[0].push(uvb[1]);
uvs[0].push(uvc[0]);
uvs[0].push(uvc[1]);
uvs[0].push(uvd[0]);
uvs[0].push(uvd[1]);
In the following code, we create a face object and store the calculated indices in the
corresponding face properties ( a , b , d ). The normals of all vertices lie on the same
plane. Hence, the normals are cloned from the normal object (0, 0, 1) and copied to
the vertexNormals array of the face object:
var face = new Face();
face.a=a;
face.b=b;
face.c=d;
face.vertexNormals=[];
face.vertexNormals["a"]=vec3.clone(normal);
face.vertexNormals["b"]=vec3.clone(normal);
face.vertexNormals["c"]=vec3.clone( normal);
this.faces.push( face );
In the following code, faceIndex maintains the count of the number of face
objects stored in the faces array, and we store the UV indices at the corresponding
faceIndex element in the faceVertexUvs array:
this.faceVertexUvs[0][faceIndex]=[];
this.faceVertexUvs[0][faceIndex]["a"]= faceUVIndex;
this.faceVertexUvs[0][faceIndex]["b"]= faceUVIndex+1;
this.faceVertexUvs[0][faceIndex]["c"]= faceUVIndex+3;
faceIndex=faceIndex+1;
In the following code, as there are two faces per segment, we repeat the process of
creating and adding the second face to the faces array and store their corresponding
UV indices in the faceVertexUvs array of the geometry:
face = new Face();
face.a=b;
face.b=c;
face.c=d;
face.vertexNormals=[];
face.vertexNormals["a"]=vec3.clone(normal);