3D sidescroller movement

[Rick]

Let's say I want to create a sidescrolling game in 3D. Let's also say I want to not use the character controller object but instead just use the model mesh to move around. I want the character to also be able to move somewhat "up" and "down" (think double dragon). So if I start out on the x axis being forward and backward this moving "up" and "down" would actually be the z axis.

 

I don't want to use MoveEntity() but PositionEntity() for learning some math sake, so I'm trying to use vector math here to figure out how I can handle this. I don't want to hardcode the axis that "forward" means positive X because I'm thinking about having the character be able to rotate and go down other paths which would screw that all up. The camera would rotate with him to always keep the sidescrolling perspective however.

 

So I'm trying to figure out how can I keep things relative?

 

So initially "forward" is down the positive X axis and that would be the D key. So even if I allow a 90 degree rotation at some point the D key would always be "forward", but that might be down the Z axis if I allow rotation.

 

The other thing is that A would rotate the character and could be looked at as "forward" also but it's really "backward" with the model just rotated. My main issue is that the W and S key would originally move in the Z axis, and be a strafing effect. When I'm facing "right" down the positive x W would strafe relative left, but when I'm facing "left" down the X axis at first (but remember this could be the Z axis also if I rotate down another path) W would need to strafe relative right.

 

I guess I don't even know if any of this even makes sense It's kind of confusing in my head.

 

Any help or pointers would be nice.

 

Thanks

[Canardia]

I would keep learning and game development seperate things. When I need to learn and test something, I make a seperate project, and when it works then I copy it back to the game code.

 

I would make all movement with physics. You could have invisible walls around the scene, so that the character is jailed into a 2D world.

[Rick]

I understand what you would do but I'm asking specifically in the way I phrased it. I don't want to take another approach, I'm more interested in learning with the vector math and was wondering if I could start a dialog with some people who are willing to lend a hand at the given approach I'm taking.

 

You could have invisible walls around the scene, so that the character is jailed into a 2D world.

 

That's not really an issue I have. I know how to do that, it's more the vector movement that I'm curious about.

[Michael Betke]

I really would like to see a scrolling game.

If I ever make a game with Leadwerks it would be a scroller like the old "Raptor" game.

[AndyGFX]

Try this my hint:

 

- when you press move control, define movement vector for player not from model (Z axis vector), but from camera axis vectors, because camera is always oriented toward screen and looks on level/player from side when we talk about "side scroll" control.

 

Pseudo math code for movement:

 

to right/left:

Pivot_pos = Pivot_pos +/- Camera_X_axis_vetor

 

to up/down:

Pivot_pos = Pivot_pos +/- Camera_Z_axis_vetor

 

with this, player movement always looks like "side scroll", aligned to camera view.

[Rick]

That's a really good idea. I didn't even think about using the camera vectors to help know information about the player controls, but it makes sense. I'll play around with that, thanks!