Re: d3dx8: patch1: Implement D3DXBoxBoundProbe

[H. Verbeet]

2008/7/27 David Adam <david.adam.cnrs(a)gmail.com>:
> +     ortho = D3DXVec3Dot(praydirection, &normal[i]);
> +     if ( ortho )
> +     {
> +      t = D3DXVec3Dot(praydirection, &normal[i]) / ortho;
> This doesn't make much sense, t will always be close to zero this way.
> +    rayposition.x = -3.0f; rayposition.y = 1.0f; rayposition.z = -2.0f;
> +    result = D3DXBoxBoundProbe(&bottom_point, &top_point, &rayposition, &raydirection);
> +    ok(result == TRUE, "expected TRUE, received FALSE\n");
> This succeeds because rayposition lies on one of the faces of the box.
> I think it would be useful to also add a test where rayposition lies
> outside the box but where the ray still intersects the box.

In general, also note that the fact that the box is always
axis-aligned means the normal is always 0 in two of the three
directions. This simplifies the equations a bit.

d3dx8: patch1: Implement D3DXBoxBoundProbe

[H. Verbeet]

2008/7/28 H. Verbeet <hverbeet(a)gmail.com>:
> 2008/7/27 David Adam <david.adam.cnrs(a)gmail.com>:
> > +     ortho = D3DXVec3Dot(praydirection, &normal[i]);
> > +     if ( ortho )
> > +     {
> > +      t = D3DXVec3Dot(praydirection, &normal[i]) / ortho;
> > This doesn't make much sense, t will always be close to zero this way.

That should read "one" rather than "zero" of course. (Thanks to
Michael Karcher for spotting that).