public override void Update(float time)
{
int p;
float lt;
// eg.
// p..p..p..p..p..p..p
// 1..2..3..4..5..6..7
// want p to be 1, 2, 3, 4, 5, 6
if (time == 1)
{
p = Points.Count - 1;
lt = 1;
}
else
{
p = (int)(time / DeltaT);
lt = (time - DeltaT * p) / DeltaT;
}
// Interpolate
var c = Points.Count - 1;
CCPoint pp0 = Points [Math.Min(c, Math.Max(p - 1, 0))];
CCPoint pp1 = Points [Math.Min(c, Math.Max(p + 0, 0))];
CCPoint pp2 = Points [Math.Min(c, Math.Max(p + 1, 0))];
CCPoint pp3 = Points [Math.Min(c, Math.Max(p + 2, 0))];
CCPoint newPos = CCSplineMath.CCCardinalSplineAt(pp0, pp1, pp2, pp3, Tension, lt);
// Support for stacked actions
CCNode node = Target;
CCPoint diff = node.Position - PreviousPosition;
if (diff.X != 0 || diff.Y != 0)
{
AccumulatedDiff = AccumulatedDiff + diff;
newPos = newPos + AccumulatedDiff;
}
UpdatePosition(newPos);
}
public static void DrawCardinalSpline(List <CCPoint> config, float tension, int segments)
{
int p;
float lt;
float deltaT = 1.0f / config.Count;
int count = config.Count;
var vertices = new CCPoint[segments + 1];
for (int i = 0; i < segments + 1; i++)
{
float dt = (float)i / segments;
// border
if (dt == 1)
{
p = count - 1;
lt = 1;
}
else
{
p = (int)(dt / deltaT);
lt = (dt - deltaT * p) / deltaT;
}
// Interpolate
int c = config.Count - 1;
CCPoint pp0 = config[Math.Min(c, Math.Max(p - 1, 0))];
CCPoint pp1 = config[Math.Min(c, Math.Max(p + 0, 0))];
CCPoint pp2 = config[Math.Min(c, Math.Max(p + 1, 0))];
CCPoint pp3 = config[Math.Min(c, Math.Max(p + 2, 0))];
vertices[i] = CCSplineMath.CCCardinalSplineAt(pp0, pp1, pp2, pp3, tension, lt);
}
DrawPoly(vertices, DrawColor);
}