3D Engine?

[dragonguy]

My game's 3D Engine will be simpler than you'd think(when it's made), objects only have X and Y coordinates and when shown in game, they will be at a constant Y position on the display surface, I need the math to position their X on the display surface, the camera will only ever rotate on one axis.

I'm not going to use the 3D Actives because it will make things lagg, considering the thousands of objects during runtime.

3D Actives places objects with X, Y & Z coordinates on to a X & Y Display surface.

What I want to do is to place objects with X & Y coordinates on to a X Display Surface.

If you have played Wolfenstein 3D or Spear of Destiny, I basically want to make that game.

[Dynasoft]

I already gave you the formula.

[Werbad]

You will still not be able to display walls correctly... But I see that it's impossible to explain that for you, so I'll just let you realize that on your own.

[Anders]

Just for you dragonguy:
http://www.clickteam.com/epicenter/ubbthreads.php?ubb=showflat&Number=95752

[dragonguy]

I understand that it will be impossible to do walls properly but I have something close to that, thats a nice example andos but I still don't have the math I require to make my game work.

[Dynasoft]

You'll find it in the example, or at the site I linked to.

[dragonguy]

I just need a basic working formula nothing fancy, I have already posted the specifications it requires I just want one basic forumla to make my wolf3d style game work.

I tried a formula I came up with (It's posted here, somewhere) but that one didn't work but I do not know why it didn't work.

The formula dynasoft gave me didn't tell me how to position objects, it was interesting and nice to look at even if you can't make 100 percent sense of it.

All I need somebody to post a mathematical formula for positioning objects correctly and I will test it to see if it works and if it doe's work, thanks to you.

[Bruto]

You will still not be able to display walls correctly... But I see that it's impossible to explain that for you, so I'll just let you realize that on your own.

LOL..

[dragonguy]

Things that I need help with:

1) Formula for Positioning objects correctly.

2) Formula for Scaling.

3) Making objects invisible when they are behind you.

[Dynasoft]

The scale of an object is the 1 / dot(objectlocation-cameralocation,cameradirection). MMF doesn't have the dot product function because it doesn't support vector variables, so you'll have to adapt it. Basically the scale of an object is 1.0 / its distance from the camera.
The dot() is <1 if you shouldn't draw the object.
An object's position on screen is (objectlocation-cameralocation)*RotationMatrix(-camerarotation)*scale*(screenheight/2)+(screenwidth/2,screenheight/2) where scale is what is calculated above, but MMF doesn't support matrixes OR vectors so you'll have to read up on them and adapt it. You will end up with a VERY long formula.

This is a simple version that doesn't deal with camera FOV, assumes the objects don't rotate (always face the camera) and that your 3d coordinate system is x->right y->up z->forwards.