private void AddPoint(TrailPoint point, Vector3 direction, float uv)
{
float lifePercent = (Time.time - point.creationTime) / lifetime;
float halfWidth = width.Evaluate(lifePercent);
float normalStrength = strength.Evaluate(lifePercent);
Color normalStrengthColor = new Color(normalStrength, normalStrength, normalStrength, normalStrength);
direction.Normalize();
Vector3 pos = point.pos;
Vector3 right = Vector3.Cross(upDir, direction);
vertices.Add(pos - right * halfWidth);
vertices.Add(pos + right * halfWidth);
uvs.Add(new Vector2(0, uv));
uvs.Add(new Vector2(1, uv));
normals.Add(upDir);
normals.Add(upDir);
tangents.Add(new Vector4(direction.x, direction.y, direction.z, 1));
tangents.Add(new Vector4(direction.x, direction.y, direction.z, 1));
colors.Add(normalStrengthColor);
colors.Add(normalStrengthColor);
int lastVert = vertices.Count - 1;
if (lastVert >= 3)
{
triangles.Add(lastVert - 1);
triangles.Add(lastVert);
triangles.Add(lastVert - 2);
triangles.Add(lastVert - 2);
triangles.Add(lastVert - 3);
triangles.Add(lastVert - 1);
}
}
private void UpdateMesh(List <TrailPoint> renderPoints)
{
mesh.Clear();
if (renderPoints.Count < 2)
{
return;
}
//Clear lists
vertices.Clear();
triangles.Clear();
uvs.Clear();
normals.Clear();
tangents.Clear();
colors.Clear();
float uvFactor = 1.0f / (renderPoints.Count - 1);
//Iterate though all previous points
for (int i = 0; i < renderPoints.Count; i++)
{
//First point
TrailPoint point = renderPoints[i];
if (i == 0)
{
AddPoint(point, renderPoints[i + 1].pos - point.pos, 0);
continue;
}
//Last point
TrailPoint lastPoint = renderPoints[i - 1];
if (i == renderPoints.Count - 1)
{
AddPoint(point, point.pos - lastPoint.pos, 1);
break;
}
//In-between points
TrailPoint nextPoint = renderPoints[i + 1];
AddPoint(point, nextPoint.pos - lastPoint.pos, i * uvFactor);
}
mesh.vertices = vertices.ToArray();
mesh.triangles = triangles.ToArray();
mesh.uv = uvs.ToArray();
mesh.normals = normals.ToArray();
mesh.tangents = tangents.ToArray();
mesh.colors = colors.ToArray();
//Those only work in Unity 5.2 and above... shouldn't be much faster anyways.
//mesh.SetVertices(vertices);
//mesh.SetTriangles(triangles, 0);
//mesh.SetUVs(0, uvs);
//mesh.SetNormals(normals);
//mesh.SetTangents(tangents);
//mesh.SetColors(colors);
}
