DotRecastNetSim/src/DotRecast.Recast.Toolset/Tools/Gizmos/CylinderGizmo.cs

76 lines
3.0 KiB
C#

using DotRecast.Core;
using static DotRecast.Core.RcMath;
using static DotRecast.Recast.Toolset.Tools.Gizmos.GizmoHelper;
namespace DotRecast.Recast.Toolset.Tools.Gizmos
{
public class CylinderGizmo : IRcGizmoMeshFilter
{
public readonly float[] vertices;
public readonly int[] triangles;
public readonly RcVec3f center;
public readonly float[] gradient;
public CylinderGizmo(RcVec3f start, RcVec3f end, float radius)
{
center = RcVec3f.Of(
0.5f * (start.x + end.x), 0.5f * (start.y + end.y),
0.5f * (start.z + end.z)
);
RcVec3f axis = RcVec3f.Of(end.x - start.x, end.y - start.y, end.z - start.z);
RcVec3f[] normals = new RcVec3f[3];
normals[1] = RcVec3f.Of(end.x - start.x, end.y - start.y, end.z - start.z);
RcVec3f.Normalize(ref normals[1]);
normals[0] = GetSideVector(axis);
normals[2] = RcVec3f.Zero;
RcVec3f.Cross(ref normals[2], normals[0], normals[1]);
RcVec3f.Normalize(ref normals[2]);
triangles = GenerateCylindricalTriangles();
RcVec3f trX = RcVec3f.Of(normals[0].x, normals[1].x, normals[2].x);
RcVec3f trY = RcVec3f.Of(normals[0].y, normals[1].y, normals[2].y);
RcVec3f trZ = RcVec3f.Of(normals[0].z, normals[1].z, normals[2].z);
vertices = GenerateCylindricalVertices();
float halfLength = 0.5f * axis.Length();
gradient = new float[vertices.Length / 3];
RcVec3f v = new RcVec3f();
for (int i = 0; i < vertices.Length; i += 3)
{
float offset = (i >= vertices.Length / 2) ? -halfLength : halfLength;
float x = radius * vertices[i];
float y = vertices[i + 1] + offset;
float z = radius * vertices[i + 2];
vertices[i] = x * trX.x + y * trX.y + z * trX.z + center.x;
vertices[i + 1] = x * trY.x + y * trY.y + z * trY.z + center.y;
vertices[i + 2] = x * trZ.x + y * trZ.y + z * trZ.z + center.z;
if (i < vertices.Length / 4 || i >= 3 * vertices.Length / 4)
{
gradient[i / 3] = 1;
}
else
{
v.x = vertices[i] - center.x;
v.y = vertices[i + 1] - center.y;
v.z = vertices[i + 2] - center.z;
RcVec3f.Normalize(ref v);
gradient[i / 3] = Clamp(0.57735026f * (v.x + v.y + v.z), -1, 1);
}
}
}
private RcVec3f GetSideVector(RcVec3f axis)
{
RcVec3f side = RcVec3f.Of(1, 0, 0);
if (axis.x > 0.8)
{
side = RcVec3f.Of(0, 0, 1);
}
RcVec3f forward = new RcVec3f();
RcVec3f.Cross(ref forward, side, axis);
RcVec3f.Cross(ref side, axis, forward);
RcVec3f.Normalize(ref side);
return side;
}
}
}