// remember to convert fovy from degree to radius before calling tan
void I_my_gluPerspective(GLdouble fovy, GLdouble aspect,
GLdouble zNear, GLdouble zFar)
{
GLdouble frustumW, frustumH;
frustumH = tanf( fovy / 360.0 * PI ) * zNear;
frustumW = frustumH * aspect;
I_my_glFrustum(-frustumW, frustumW, -frustumH, frustumH, zNear, zFar);
}
// remember to convert fovy from degree to radius before calling tan
void I_my_gluPerspective(GLdouble fovy, GLdouble aspect,
GLdouble zNear, GLdouble zFar)
{
GLdouble top, bottom, right, left;
printf("Call to I_my_gluPerspective\n");
top = zNear * tan(fovy*PI/360);
bottom = -top;
right = top * aspect;
left = -right;
I_my_glFrustum(left, right, bottom, top, zNear, zFar);
}
