normal2& normal2::direction_between( const point2& src , const point2& dst )
{
//vec2 vsrc(src._x , src._y);
//vec2 vdst(dst._x , dst._y);
_x = dst.x() - src.x();
_y = dst.y() - src.y();
return __normalize();
}
void OpenGLES1RenderManager::gluLookAt(GLfloat eyex, GLfloat eyey, GLfloat eyez, GLfloat centerx,
GLfloat centery, GLfloat centerz, GLfloat upx, GLfloat upy,GLfloat upz)
{
GLfloat forward[3], side[3], up[3];
GLfloat m[4][4];
forward[0] = centerx - eyex;
forward[1] = centery - eyey;
forward[2] = centerz - eyez;
up[0] = upx;
up[1] = upy;
up[2] = upz;
__normalize(forward);
/* Side = forward x up */
__cross(forward, up, side);
__normalize(side);
/* Recompute up as: up = side x forward */
__cross(side, forward, up);
__gluMakeIdentityf(&m[0][0]);
m[0][0] = side[0];
m[1][0] = side[1];
m[2][0] = side[2];
m[0][1] = up[0];
m[1][1] = up[1];
m[2][1] = up[2];
m[0][2] = -forward[0];
m[1][2] = -forward[1];
m[2][2] = -forward[2];
glMultMatrixf(&m[0][0]);
glTranslatef(-eyex, -eyey, -eyez);
}
normal2& normal2::operator = (const vec2& a)
{
_x = a.x;
_y = a.y;
return __normalize();
}