what formula can i use to calculate normal for vertex??
i use this parametric formula for my object:
x=1.6f*(cos(0.5angle1)cos(0.5angle1)cos(0.5angle1));
y=1.6f(cos(angle2)sin(0.5angle1)*cos(angle2)sin(0.5angle1)cos(angle2)sin(0.5angle1));
z=1.6fsin(angle2)sin(0.5angle1);
can anyone pls give me example how to use parametric function in opengl??i put it under double loop and i failed to get good shape. i just started studying com graphics this week.
[This message has been edited by caesar5 (edited 03-01-2004).]
[This message has been edited by caesar5 (edited 03-01-2004).]
Iterate through all triangles of your mesh. For each vertex of each triangle, take the cross product of the two edges the vertex is part of and store it associated to the vertex (you’ll get several normals for each vertex, because every vertex can be part of several faces). Add all normals for each vertex. Normalize. Voila
Caesar, you should take advantage of this fact and use the gradient operator to find your normals (ask if you need more info on this). You don’t need to pre-tesselate or use any adjacency information then, and the normals will probably end up being smoother.