1、获得顶点的数据集合protected override Vector3[] GetVertices()

{

var points = new Vector3[_circularSideCount];//保存底面圆形的点集合

for (int i = 0; i < _circularSideCount; i++)

{

var rad = i * 1.0f / _circularSideCount * Mathf.PI * 2;

var cos = Mathf.Cos(rad) * _radius;

var sin = Mathf.Sin(rad) * _radius;

points[i] = new Vector3(cos, -_height * 0.5f, sin) - _verticeOffset;

}

int curIndex = 0;//当前索引

int arrayLen = (_circularSideCount + 1) * 3;//顶点数组的长度

var vertices = new Vector3[arrayLen];

//底面

vertices[curIndex++] = new Vector3(0, -_height * 0.5f, 0) - _verticeOffset;

for (int i = 0; i < _circularSideCount; i++)

{

vertices[curIndex++] = points[i];

}

//侧面

var topPoint = new Vector3(0, _height * 0.5f, 0) - _verticeOffset;//顶点的位置

for (int i = 0; i < _circularSideCount; i++)

{

vertices[curIndex++] = points[i];

vertices[curIndex++] = topPoint;

}

vertices[curIndex] = points[0];

vertices[curIndex++] = topPoint;

return vertices;

}

2、获得法线方向的数据集合protected override Vector3[] GetNormals()

{

int curIndex = 0;

int arrayLen = (_circularSideCount + 1) * 3;//法线数组的长度

var normals = new Vector3[arrayLen];

//底面

for (int i = 0; i <= _circularSideCount; i++)

{

normals[curIndex++] = Vector3.down;

}

//侧面

for (int i = 0; i <= _circularSideCount; i++)

{

var rad = i * 1.0f / _circularSideCount * Mathf.PI * 2;

var cos = Mathf.Cos(rad);

var sin = Mathf.Sin(rad);

normals[curIndex++] = new Vector3(cos, 0, sin);

normals[curIndex++] = new Vector3(cos, 0, sin);

}

return normals;

}

3、获得三角面顶点的索引protected override int[] GetTriangles()

{

int curIndex = 0;

int arrayLen = _circularSideCount * 3 + _circularSideCount * 3;//数组长度

var triangles = new int[arrayLen];

//底面

for (int i = 0; i < _circularSideCount - 1; i++)

{

triangles[curIndex++] = 0;

triangles[curIndex++] = i + 1;

triangles[curIndex++] = i + 2;

}

triangles[curIndex++] = 0;

triangles[curIndex++] = _circularSideCount;

triangles[curIndex++] = 1;

//侧面

int startIndex = _circularSideCount + 1;

for (int i = 0; i < (_circularSideCount - 1) * 2; i += 2)

{

triangles[curIndex++] = startIndex + i;

triangles[curIndex++] = startIndex + i + 1;

triangles[curIndex++] = startIndex + i + 2;

}

triangles[curIndex++] = startIndex + (_circularSideCount - 1) * 2;

triangles[curIndex++] = startIndex + (_circularSideCount - 1) * 2 + 1;

triangles[curIndex] = startIndex;

return triangles;

}

4、获得UV坐标的数据集合protected override Vector2[] GetUVs()

{

int curIndex = 0;

int arrayLen = (_circularSideCount + 1) * 3;

var uvs = new Vector2[arrayLen];

//底面

uvs[curIndex++] = new Vector2(0.5f, 0.5f);

for (int i = 0; i < _circularSideCount; i++)

{

var rad = i * 1.0f / _circularSideCount * Mathf.PI * 2;

var cos = Mathf.Cos(rad);

var sin = Mathf.Sin(rad);

uvs[curIndex++] = new Vector2(cos, sin);

}

//侧面

float value = 1.0f / _circularSideCount;

for (int i = 0; i <= _circularSideCount; i++)

{

uvs[curIndex++] = new Vector2(value * i, 0);

uvs[curIndex++] = new Vector2(value * i, 1);

}

return uvs;

}

效果如下：