How to make an on-rail shooter? [SOLVED]

[flim]

I want to make an on-rail shooter like Starfox, Panzer Dragoon, SWTOR, which the camera is run on a fixed path, the player control a space ship.

Can I use ShiVa for this kind of game? My concern is how to make the "track" for the camera in ShiVa.

[psychicsoftware]

I have been doing this exact thing for a rail-shooter I'm making.

The camera's path is stored in an XML object as a set of keypoints (position and rotation), then once per frame I'm moving the camera forward a little bit along these points, and using catmullrom curves (math.evaluateCatmullRom) to interpolate the current position/rotation.

Also, I have found it useful to attach the spaceships to the camera's coordinate system by parenting them: object.setParent ( hShip, hCam, false )

Here's a demo of my current game with all of this happening (the rails take the spaceship past Earth and the Moon):
http://www.psychicsoftware.com/demo/afterburndemo.html

[flim]

Is it possible to use AnimClip Editor for editing the camera path? Is it possible if I want the camera slowdown or pause for a while for a particular keypoint?

[psychicsoftware]

I haven't ever used AnimClips, hopefully someone else can answer that one. With the approach I'm using, the camera's speed along the path is totally under your control of course, so slowing/stopping is easy.

[flim]

I see, but how do you determine the position/rotation of the keypoint without using a visual tool?

I check the manual but there is no example for the function math.evaluateCatmullRom(). What is the meaning of the nValue1..4 parameters?

[flim]

Hi,

Could you provide an example how to use math.evaluateCatmullRom()? I still can't figure out because the documentation is almost empty.

[NiCoX]

Hi,

Not a direct answer to your question, but I think this is something like that you are looking for:

http://developer.stonetrip.com/Download/SampleCode/TEST_EvalCurve_20120516.ste

Also concerning AnimClips, this can also be a solution. And you can slow down playback using animation.setPlaybackSpeed.

Hope this helps

[broozar]

I still can't figure out because the documentation is almost empty.

shape.curves online API is now up to date.

[flim]

Hi,

Not a direct answer to your question, but I think this is something like that you are looking for:

http://developer.stonetrip.com/Download/SampleCode/TEST_EvalCurve_20120516.ste

Also concerning AnimClips, this can also be a solution. And you can slow down playback using animation.setPlaybackSpeed.

Hope this helps

Thanks! It seems the actor not rotate, how to add rotation to this script?

[broozar]

you can choose to either object.lookAt() at a certain object (and optionally switch between them), or store the previous position inside a table or 3 member variables, and define a direction vector with the current set of coordinates.

[flim]

I think using AnimClips to make the camera path is more intuitive for me. Is there a way to draw a debug line of the animation path in Scene viewer?

[FF.Fan]

yes, look here :
http://www.stonetrip.com/developer/doc/api/debug-drawLine

[flim]

Hi,

Could you provide an example how to use math.evaluateCatmullRom()? I still can't figure out because the documentation is almost empty.

Anyone can help? I search on forum and Internet but didn't find any example.

[broozar]

[edit] i was wrong

[flim]

...

If math.evaluate..() just for 2D, how psychicsoftware use it for it's rail shooter? Maybe each math.evaluate..() only calculate for one axis?