public void SelectLine(WCell.Util.Graphics.Vector3 p1, WCell.Util.Graphics.Vector3 p2, Color color, bool doNotReplace = true)
{
const float halfLineWidth = 0.5f;
var s1 = p1 - halfLineWidth;
var s2 = p1 + halfLineWidth;
var t1 = p2 - halfLineWidth;
var t2 = p2 + halfLineWidth;
s1.Z = s2.Z = Math.Max(s1.Z, s2.Z);
t1.Z = t2.Z = Math.Max(t1.Z, t2.Z);
var tri1 = new Triangle(s1, s2, t2);
var tri2 = new Triangle(t2, t1, s1);
Select(ref tri1, doNotReplace, color);
Select(ref tri2, true, color);
}
public void SelectPoint(WCell.Util.Graphics.Vector3 p, Color color, bool doNotReplace = true)
{
const float sideDist = 0.5f;
var p1 = p;
var p2 = p;
var p3 = p;
p1.X += sideDist;
p2.X -= sideDist;
p2.Y -= sideDist;
p3.X -= sideDist;
p3.Y += sideDist;
var tri1 = new Triangle(p1, p2, p3);
Select(ref tri1, doNotReplace, color);
}
public void Select(ref Triangle tri, bool doNotReplace, Color color)
{
var v = _cachedVertices.Length;
var i = _cachedIndices.Length;
if (doNotReplace)
{
Array.Resize(ref _cachedVertices, _cachedVertices.Length + 3);
Array.Resize(ref _cachedIndices, _cachedIndices.Length + 3);
}
else
{
v = i = 0;
_cachedVertices = new VertexPositionNormalColored[3];
_cachedIndices = new int[3];
}
// add vertices
var normal = WCell.Util.Graphics.Vector3.Cross(tri.Point3 - tri.Point1, tri.Point2 - tri.Point1).ToXna();
normal.Normalize();
_cachedVertices[v] = new VertexPositionNormalColored(tri.Point1.ToXna(),
color,
normal);
_cachedVertices[v+1] = new VertexPositionNormalColored(tri.Point2.ToXna(),
color,
normal);
_cachedVertices[v+2] = new VertexPositionNormalColored(tri.Point3.ToXna(),
color,
normal);
// add indices
_cachedIndices[i] = v;
_cachedIndices[i+1] = v+1;
_cachedIndices[i+2] = v+2;
}
public void GetTriangle(int triIndex, out Triangle triangle)
{
triangle = new Triangle
{
Point1 = TerrainVertices[TerrainIndices[triIndex++]],
Point2 = TerrainVertices[TerrainIndices[triIndex++]],
Point3 = TerrainVertices[TerrainIndices[triIndex]]
};
}
public void Select(ref Triangle tri, bool doNotReplace = true)
{
Select(ref tri, doNotReplace, SelectedTriangleColor);
}
/// <summary>
/// Intersects a ray with the given triangle
/// I think it does not currently work?
/// </summary>
/// <param name="dist">The distance of the given point</param>
public static bool RayTriangleIntersect2(Ray ray, Triangle tri, out float dist)
{
// See http://www.cs.princeton.edu/courses/archive/fall00/cs426/lectures/raycast/sld017.htm
var normal = tri.CalcNormalizedNormal();
var d = Vector3.Dot(normal, tri.Point1);
dist = -(Vector3.Dot(ray.Position, normal) + d) / (Vector3.Dot(ray.Direction, normal));
if (float.IsNaN(dist) || dist < 0)
{
// no intersection
return false;
}
// intersection point
var p = ray.Position + ray.Direction * dist;
// See http://www.cs.princeton.edu/courses/archive/fall00/cs426/lectures/raycast/sld018.htm
var n1 = Vector3.Cross(tri.Point1 - ray.Position, tri.Point2 - ray.Position);
n1.Normalize();
var d1 = -Vector3.Dot(ray.Position, n1);
if (Vector3.Dot(p, n1) + d1 < 0)
{
return false;
}
var n2 = Vector3.Cross(tri.Point2 - ray.Position, tri.Point3 - ray.Position);
n2.Normalize();
var d2 = -Vector3.Dot(ray.Position, n2);
if (Vector3.Dot(p, n2) + d2 < 0)
{
return false;
}
var n3 = Vector3.Cross(tri.Point3 - ray.Position, tri.Point1 - ray.Position);
n3.Normalize();
var d3 = -Vector3.Dot(ray.Position, n3);
if (Vector3.Dot(p, n3) + d3 < 0)
{
return false;
}
return true;
}
public static int GetSharedEdgeMask(this Triangle tri1, Triangle tri2)
{
var mask = 0;
if (tri1.Point1.Equals(tri2.Point1) || tri1.Point1.Equals(tri2.Point2) || tri1.Point1.Equals(tri2.Point3))
{
mask = TrianglePointA;
}
if (tri1.Point2.Equals(tri2.Point1) || tri1.Point2.Equals(tri2.Point2) || tri1.Point2.Equals(tri2.Point3))
{
mask |= TrianglePointB;
}
if (tri1.Point3.Equals(tri2.Point1) || tri1.Point3.Equals(tri2.Point2) || tri1.Point3.Equals(tri2.Point3))
{
mask |= TrianglePointC;
}
return mask;
}
