// 重置数据
private void ResetData()
{
// 点集合
_pointLists.Clear();
// 线段总长度
_totalLength = _currentRunTime = 0;
// 初始位置
_prevPos = new BVector3(this.pointArr[0], 0, 0);
}
public void ComputeBezier(float dt, float runTime)
{
// 把时间从 [0,runTime] 映射到 [0,1] 之间
float t = this._currentRunTime / runTime;
float x = 0, y = 0, z = 0;
//控制点数组
float n = this.pointArr.Length - 1;
for (int i = 0; i < this.pointArr.Length; i++)
{
Vector3 item = pointArr[i];
if (i == 0)
{
x += item.x * (float)(Math.Pow((1 - t), n - i) * Math.Pow(t, i));
y += item.y * (float)(Math.Pow((1 - t), n - i) * Math.Pow(t, i));
z += item.z * (float)(Math.Pow((1 - t), n - i) * Math.Pow(t, i));
}
else
{
//factorial为阶乘函数
x += Factorial(n) / Factorial(i) / Factorial(n - i) * item.x * (float)Math.Pow((1 - t), n - i) * (float)Math.Pow(t, i);
y += Factorial(n) / Factorial(i) / Factorial(n - i) * item.y * (float)Math.Pow((1 - t), n - i) * (float)Math.Pow(t, i);
z += Factorial(n) / Factorial(i) / Factorial(n - i) * item.z * (float)Math.Pow((1 - t), n - i) * (float)Math.Pow(t, i);
}
}
// 计算两点距离
float length = (float)(Math.Sqrt(Math.Pow(this._prevPos.pos.x - x, 2) + Math.Pow(this._prevPos.pos.y - y, 2) + Math.Pow(this._prevPos.pos.z - z, 2)));
BVector3 v3 = new BVector3(new Vector3(x, y, z), length, 0);
// 存储当前节点z
this._pointLists.Add(v3);
this._prevPos = v3;
// 累计长度
this._totalLength += length;
// 累计时间
this._currentRunTime += dt;
}
public BVector3 ComputeBezierPoint(float curTime, float runTime)
{
// 把时间从 [0,runTime] 映射到 [0,1] 之间
float t = Evaluate(ease, curTime, runTime);
float x = 0, y = 0, z = 0;
//控制点数组
float n = pointArr.Length - 1;
for (int i = 0; i < pointArr.Length; i++)
{
Vector3 item = pointArr[i];
if (i == 0)
{
x += item.x * (float)(Math.Pow((1 - t), n - i) * Math.Pow(t, i));
y += item.y * (float)(Math.Pow((1 - t), n - i) * Math.Pow(t, i));
z += item.z * (float)(Math.Pow((1 - t), n - i) * Math.Pow(t, i));
}
else
{
//factorial为阶乘函数
x += Factorial(n) / Factorial(i) / Factorial(n - i) * item.x * (float)Math.Pow((1 - t), n - i) * (float)Math.Pow(t, i);
y += Factorial(n) / Factorial(i) / Factorial(n - i) * item.y * (float)Math.Pow((1 - t), n - i) * (float)Math.Pow(t, i);
z += Factorial(n) / Factorial(i) / Factorial(n - i) * item.z * (float)Math.Pow((1 - t), n - i) * (float)Math.Pow(t, i);
}
}
// 计算两点距离
float length = (float)(Math.Sqrt(Math.Pow(_prevPos.pos.x - x, 2) + Math.Pow(_prevPos.pos.y - y, 2) + Math.Pow(_prevPos.pos.z - z, 2)));
BVector3 v3 = new BVector3(new Vector3(x, y, z), length, 0);
// 存储当前节点z
_pointLists.Add(v3);
_prevPos = v3;
// 累计长度
_totalLength += length;
return(v3);
}
