On May 20, 8:40=A0pm, Sourcerer <enlorkMA...@[EMAIL PROTECTED]
> wrote:
> So I started out with OpenGL recently and I wanted to make a simple
> simulation of our Solar System (although the main light source isn't the
> Sun). It looks quite nice when viewed from above.
>
> My next move was to implement changing perspectives. For example, when I
> hit a button on my keyboard, I should be looking from the Earth towards
th=
e
> Sun. And the Earth, of course, keeps circling the Sun along with me on
it.=
>
> But alas, with this change of perspective, the light source moved too,
and=
> it moves with me all the time. I defined light thus:
>
> GLfloat lightSourcePosition[] =3D {10.0, 10.0, 10.0, 0.0};
> GLfloat lightSourceDirection[] =3D {0.0, 0.0, 0.0, 0.0};
>
> glLightfv(GL_LIGHT0, GL_POSITION, lightSourcePosition);
> glLightfv(GL_LIGHT0, GL_SPOT_DIRECTION, lightSourceDirection);
>
> glEnable(GL_LIGHTING);
> glEnable(GL_LIGHT0);
>
> I change perspective by loading identity matrix and then calling
> gluLookAt() to say where I want to look.
>
> So, why does this light move with me? How can I make it stay at the same
> place all the time while I change camera position?
>
> The Red Book isn't very helpful in this issue because the example given
> there has stationary light only until I change perspective, so it's no
> good.
>
> --
> "Let's see what's out there. Engage."
> Jean Luc Picard, Star Trek: TNG, Encounter at
Farpointhttp://pinpoint.word=
press.com/
Hi m8,
Just repeat the following lines again after the gluLookAt command:
gluLookAt(....
glLightfv(GL_LIGHT0, GL_POSITION, lightSourcePosition);
glLightfv(GL_LIGHT0, GL_SPOT_DIRECTION, lightSourceDirection);
it will work.
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