3D idea

[Flexibal]

when you rotate the camera in a 3d world, you have to rotate the whole world in the opposite direction... which could mean millions of polys.

so i had this idea - instead of rotating polys, why not just project the world on a rotated plane?

our 3d objects have three coords per point... but our screen is only a 2d plane. when we draw the world on the screen, we project the world on the XY plane. BUT had we projected the world on the XZ plane, it would be as if we are looking at the world down-up.... as if we rotated the camera by 90deg up.

and all we did was diving the X and Z coords by Y instead of diving the X and Y coords by Z...


so perhaps you could use this method of chaning the projection plane instead of rotating every poly in the world. i dont know how it goes with diagonal planes, but i dont think it should be too complex.





[Flexibal>

[Agamemnus]

http://forum.qbasicnews.com/viewtopic.php?t=3927

*STAB*

You can only do that if you are not creating a tree from which to decide which polygons to display.

If you decide which polygons to display and then rotate those polygons, the polygons that you have to display do not change but they should.

*STAB*

[Flexibal]

a) *UNSTAB*
b) i didnt read msg, and besides:

"how do you rotate the camera?" So, I came up with this little idea. What if I simply first translate the world in coordination with the camera, and then rotate in the opposite direction?

c) he's talking about rotation. i'm not.
d) i dont use no trees
e) *UNSTAB*




[Flexibal>

[Agamemnus]

:|

Ok, whatever.

If you don't use trees, you're going to draw all the polygons. Which makes it much easier to do rotation.

One other thing you could do is calculate all the polygons that could possibly appear for all possible rotations and then rotate self.

[relsoft]

The better the occlusion method the faster your render. That's why BSP trees are so popular. ;*)

RE: Projecting the world on a rotated plane is...

RelMode7 . ;*)