1696d1695
<    * Revised Jan 7, 2008 DB
1699,1701c1698,1703
<     return 3*t*t * (-a+3*b-3*c+d) + 
<              6*t * (a-2*b+c) + 
<                3 * (-a+b); 
---
>     float t1 = 1.0f - t;
> 
>     return (a *  3 * t*t +
>             b *  3 * t * (2 - 3*t) +
>             c *  3 * (3*t*t - 4*t + 1) +
>             d * -3 * t1*t1);