FreeGlut smooth shading not working with glVertex

#1

Hi i experincing some problems with glShadeModel(GL_SMOOTH);
when i use glut shapes:
glutSolidSphere
its works but when i use with vertex model:

glBegin(GL_TRIANGLES);
glVertex3f(0,5,0);
glVertex3f(-3,0,0);
glVertex3f(3,0,0);
glEnd();

it doesnt want be work.
How i can enable smooth shading for it.

#2

The shading model only matters if you supply vertex colours, either directly (via glColor*) or using lighting (in which case you need to supply vertex normals via glNormal*).

GLUT’s built-in solids include vertex normals.