TSpline class

Submitted by AndyGFX on Tue, 01/18/2011 - 23:35

Here is script for spline created from 2 point and 2 control points:

SPLINE_XYZ <- 0
SPLINE_XY <- 1
SPLINE_YZ <- 2
SPLINE_XZ <- 3
class TSpline
{
A = 0;
B = 0;
C = 0;
D = 0;
E = 0;
F = 0;
G = 0;
H = 0;
I = 0;
J = 0;
K = 0;
L = 0;
mode = SPLINE_XYZ;
constructor()
{
}
function CreateSpline(p0, n0, p1, n1, mode, n0_mag , n1_mag )
{
local x0 = 0.0;
local y0 = 0.0;
local z0 = 0.0;
local x1 = 0.0;
local y1 = 0.0;
local z1 = 0.0;
local x2 = 0.0;
local y2 = 0.0;
local z2 = 0.0;
local x3 = 0.0;
local y3 = 0.0;
local z3 = 0.0;
x0 = p0.x
y0 = p0.y
z0 = p0.z
x1 = n0.x * n0_mag + p0.x
y1 = n0.y * n0_mag + p0.y
z1 = n0.z * n0_mag + p0.z
x2 = n1.x * n1_mag + p1.x
y2 = n1.y * n1_mag + p1.y
z2 = n1.z * n1_mag + p1.z
x3=p1.x
y3=p1.y
z3=p1.z
//x coefficients...
this.A = x3 - (3.0 * x2) + (3.0 * x1) - x0
this.B = (3.0 * x2) - (6.0 * x1) + (3.0 * x0)
this.C = (3.0 * x1) - (3.0 * x0)
this.D = x0
//y coefficients...
this.E = y3 - (3.0 * y2) + (3.0 * y1) - y0
this.F = (3.0 * y2) - (6.0 * y1) + (3.0 * y0)
this.G = (3.0 * y1) - (3.0 * y0)
this.H = y0
//z coefficients...
this.I = z3 - (3.0 * z2) + (3.0 * z1) - z0
this.J = (3.0 * z2) - (6.0 * z1) + (3.0 * z0)
this.K = (3.0 * z1) - (3.0 * z0)
this.L = z0
}
function Interpolate(t)
{
local v = Vector(0, 0, 0)
v.x = ((this.A * (t * t * t)) + (this.B * (t * t)) + (this.C * t) + this.D)
v.y = ((this.E * (t * t * t)) + (this.F * (t * t)) + (this.G * t) + this.H)
v.z = ((this.I * (t * t * t)) + (this.J * (t * t)) + (this.K * t) + this.L)
if (this.mode == SPLINE_XY) { v.z = 0 }
if (this.mode == SPLINE_YZ) { v.x = 0 }
if (this.mode == SPLINE_XZ) { v.y = 0 }
return v
}
}

and here is example of func_spline_mover class:

/*
File: e:/_3D_Engines/GameStart/Projects/AGFX_Game_ShiftBomber/Scripts/func_spline_mover.nut
Author: AndyGFX
*/
Include("Scripts/lib/TSpline.nut")
/*!
@short func_spline_mover
@author AndyGFX
*/
class func_spline_mover
{
/*<
<Script =
<Name = "player.nut">
<Author = "AndyGFX">
<Description = "Script for player control and moving obstacles logic.">
>
<Parameter =
<spline_start_name = <Name = "Start point name"> <Description = "Set item name as start point"> <Type = "String"> <Default = "none">>
<spline_start_cp_name = <Name = "Start control point name"> <Description = "Set item name as start control point"> <Type = "String"> <Default = "none">>
<spline_start_mag = <Name = "Start control point magn."> <Description = "Set start control point magn."> <Type = "Float"> <Default = 1.0>>
<spline_end_name = <Name = "End point name"> <Description = "Set item name as end point"> <Type = "String"> <Default = "none">>
<spline_end_cp_name = <Name = "End control point name"> <Description = "Set item name as end control point"> <Type = "String"> <Default = "none">>
<spline_end_mag = <Name = "End control point magn."> <Description = "Set end control point magn."> <Type = "Float"> <Default = 1.0>>
<spline_increment = <Name = "Move speed"> <Description = "Set speed"> <Type = "Float"> <Default = 1.0>>
>
>*/
spline_start_name = "none"
spline_start_mag = 1.0;
spline_start_cp_name = "none"
spline_end_name = "none"
spline_end_cp_name = "none"
spline_end_mag = 1.0;
spline_increment = 1.0;
spline = TSpline()
time = 0;
/*!
@short OnUpdate
Called during the scene update, each frame.
*/
function OnUpdate(item)
{
this.time = this.time + this.spline_increment;
if(time>100) {time=0.0}
local pos = this.spline.Interpolate(this.time/100.0)
ItemSetPosition(item,pos)
}
/*!
@short OnSetup
Called when the item is about to be setup.
*/
function OnSetup(item)
{
local _i_sp = SceneFindItem(g_scene,this.spline_start_name)
local _i_csp = SceneFindItem(g_scene,this.spline_start_cp_name)
local _i_ep = SceneFindItem(g_scene,this.spline_end_name)
local _i_cep = SceneFindItem(g_scene,this.spline_end_cp_name)
local cp0 = Vector(0,0,0)
cp0 = _i_csp.position()-_i_sp.position()
//cp0.Normalize()
local cp1 = Vector(0,0,0)
cp1 = _i_cep.position()-_i_ep.position()
//cp1.Normalize()
this.spline.CreateSpline(_i_sp.position(),cp0,_i_ep.position(),cp1,SPLINE_XYZ,this.spline_start_mag,this.spline_end_mag)
}
}

Assign this script to your item and set name of dummy items which are used as input to calc spline path.

Mr.Admin

Wed, 01/19/2011 - 00:39

Permalink

Nice! And thanks for sharing. I am moving this to the script sharing section as well.

AndyGFX

Wed, 01/19/2011 - 01:07

Permalink

Oops. Sorry, I forgot that exists. :)

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