protected override Mesh Build()
{
var vertices = new List <Vector3>();
var normals = new List <Vector3>();
var tangents = new List <Vector4>();
var uvs = new List <Vector2>();
var triangles = new List <int>();
// 曲線からFrenet frameを取得
var frames = curve.ComputeFrenetFrames(tubularSegments, closed);
// Tubularの頂点データを生成
for (int i = 0; i < tubularSegments; i++)
{
GenerateSegment(curve, frames, vertices, normals, tangents, i);
}
// 閉じた筒型を生成する場合は曲線の始点に最後の頂点を配置し、閉じない場合は曲線の終点に配置する
GenerateSegment(curve, frames, vertices, normals, tangents, (!closed) ? tubularSegments : 0);
// 曲線の始点から終点に向かってuv座標を設定していく
for (int i = 0; i <= tubularSegments; i++)
{
for (int j = 0; j <= radialSegments; j++)
{
float u = 1f * j / radialSegments;
float v = 1f * i / tubularSegments;
uvs.Add(new Vector2(u, v));
}
}
// 側面を構築
for (int j = 1; j <= tubularSegments; j++)
{
for (int i = 1; i <= radialSegments; i++)
{
int a = (radialSegments + 1) * (j - 1) + (i - 1);
int b = (radialSegments + 1) * j + (i - 1);
int c = (radialSegments + 1) * j + i;
int d = (radialSegments + 1) * (j - 1) + i;
triangles.Add(a); triangles.Add(d); triangles.Add(b);
triangles.Add(b); triangles.Add(d); triangles.Add(c);
}
}
var mesh = new Mesh();
mesh.vertices = vertices.ToArray();
mesh.normals = normals.ToArray();
mesh.tangents = tangents.ToArray();
mesh.uv = uvs.ToArray();
mesh.triangles = triangles.ToArray();
return(mesh);
}
List <TreeSegment> BuildSegments(TreeData data, float fromRadius, float toRadius, Vector3 normal, Vector3 binormal)
{
var segments = new List <TreeSegment>();
var points = new List <Vector3>();
var length = (to - from).magnitude;
var bend = length * (normal * data.GetRandomBendDegree() + binormal * data.GetRandomBendDegree());
points.Add(from);
points.Add(Vector3.Lerp(from, to, 0.25f) + bend);
points.Add(Vector3.Lerp(from, to, 0.75f) + bend);
points.Add(to);
var curve = new CatmullRomCurve(points);
var frames = curve.ComputeFrenetFrames(data.heightSegments, normal, binormal, false);
for (int i = 0, n = frames.Count; i < n; i++)
{
var u = 1f * i / (n - 1);
var radius = Mathf.Lerp(fromRadius, toRadius, u);
var position = curve.GetPointAt(u);
var segment = new TreeSegment(frames[i], position, radius);
segments.Add(segment);
}
return(segments);
}