[Release] Lagrange Interpolation

[Yamato]

Hello

I released before another code and I thought about this thing, my idea is to use this to move a "scrolling bar" on those so loved menus. This code gives you the y position of the point of a interpolation polynomial that passes over some certain points you determine in a smooth way.

I think this might show you better what this is:



http://en.wikipedia.org/wiki/Lagrange_polynomial

Code:

Interpolate( x, y, point )
{
    total = 0;
    for( i = 0; i < ( x.size - 1 ); i ++ )
    {
        p = 1;
        for( j = 0; j < x.size; j ++ )
            if( j != i )
                p = p * ( point - x[j] ) / ( x[i] - x[j] );
        p *= y[i];
        total += p;
    }
    return total;
}

Here it goes the code that was used for testing (it moves a text through the polynomial that passes over the 3 points, is not very smooth in the example because the waiting time is high. With MoveOverTime() function you could improove a lot the effect):

Spoiler (Click to View)

Code:

thing()
{
    x=[];
    x[0]=0;
    x[1]=50;
    x[2]=100;
    y=[];
    y[0]=-30;
    y[1]=50;
    y[2]=0;
    wait 5;
    self.cashimage = self createFontString( "default", 1.7, self );
    self.cashimage setpoint( "", "", -200, 0 );
    self.cashimage setText( "Cash" );
    self.cashimage.color = ( 1, 1, 1 );
    self.cashimage.sort = 15;
    self.cashimage.alpha = 1;
    self.cashimage.foreground = true;
    self.cashimage.glowcolor = ( 0, 1, 0 );
    self.cashimage.glowalpha = 1;
    self.cashimage setparent( level.uiParent );
    self.cashimage.hideWhenInMenu = false;
    self.cashimage.archived = false;
    wait 1;
    for( i = -10; i< 110; i++)
    {
        self.cashimage setPoint( "", "", i, Interpolate( x, y, i ) );
        wait 0.5;
    }
}

Credits:
- OMA Rhino for testing this for me.

Thanks for reading and I hope that this will get some use in some of those menus

[Nekochan]

super gibrish stuff