02/14/2002
15-462 Graphics I
24
Calculating the Normal Vectors
•Normalized cross product of any two
sides
GLfloat d1[3], d2[3], n[3];
void icoNormVec (int i) {
for (k = 0;
k < 3; k++) {
d1[k] =
vdata[tindices[i][0]] [k] – vdata[tindices[i][1]] [k];
d2[k] = vdata[tindices[i][1]] [k] – vdata[tindices[i][2]] [k];
}
normCrossProd(d1, d2, n);
glNormal3fv(n);
}