public ParticleAnchoredSpring(Particle particle, Point3D anchor, float springConstant, float restLength)
: base(particle)
{
Anchor = anchor;
SpringConstant = springConstant;
RestLength = restLength;
}
protected static Mesh CreateFromPrimitive(ParserContext context, BasicPrimitiveTessellator tessellator, Point3D center)
{
tessellator.Tessellate();
Mesh mesh = new Mesh();
mesh.Positions.AddRange(tessellator.Positions);
mesh.Indices.AddRange(tessellator.Indices);
mesh.Normals.AddRange(tessellator.Normals);
mesh.Material = context.CurrentMaterial;
mesh.Transform = new TranslateTransform
{
OffsetX = center.X,
OffsetY = center.Y,
OffsetZ = center.Z
};
return mesh;
}
public static Vector3 ToSharpDXVector3(Point3D v)
{
return new Vector3(v.X, v.Y, v.Z);
}
/// <summary>
/// Tessellates the specified bezier patch.
/// </summary>
private void TessellatePatch(BezierPatch patch, Vector3D scale)
{
// Look up the 16 control points for this patch.
Point3D[] controlPoints = new Point3D[16];
for (int i = 0; i < 16; i++)
{
int index = patch.Indices[i];
controlPoints[i] = ControlPoints[index] * scale;
}
// Is this patch being mirrored?
bool isMirrored = Math.Sign(scale.X) != Math.Sign(scale.Z);
// Create the index and vertex data.
CreatePatchIndices(isMirrored);
CreatePatchVertices(controlPoints, isMirrored);
}
public static Point3D GetPoint3D(string key, Point3D def = default(Point3D))
{
var vals = GetFloats(key);
return vals == null || vals.Length != 3 ? def : new Point3D(vals[0], vals[1], vals[2]);
}
protected void AddVertex(Point3D position, Vector3D normal, Point2D textureCoordinate)
{
AddVertex(position, normal);
TextureCoordinates.Add(textureCoordinate);
}
public VertexPositionColor(Point3D position, Vector3D color)
{
Position = position;
Color = color;
}
/// <summary>
/// Computes the tangent of a cubic bezier curve at the specified time,
/// when given four Point3D control points. This is used for calculating
/// normals (by crossing the horizontal and vertical tangent vectors).
/// </summary>
private static Vector3D BezierTangent(Point3D p1, Point3D p2,
Point3D p3, Point3D p4, float t)
{
Vector3D result = new Vector3D();
result.X = BezierTangent(p1.X, p2.X, p3.X, p4.X, t);
result.Y = BezierTangent(p1.Y, p2.Y, p3.Y, p4.Y, t);
result.Z = BezierTangent(p1.Z, p2.Z, p3.Z, p4.Z, t);
result.Normalize();
return result;
}
public Point4D(Point3D point, float w)
: this(point.X, point.Y, point.Z, w)
{
}
public static Point3D Parse(string source)
{
IFormatProvider cultureInfo = CultureInfo.InvariantCulture;
TokenizerHelper helper = new TokenizerHelper(source, cultureInfo);
string str = helper.NextTokenRequired();
Point3D pointd = new Point3D(Convert.ToSingle(str, cultureInfo), Convert.ToSingle(helper.NextTokenRequired(), cultureInfo), Convert.ToSingle(helper.NextTokenRequired(), cultureInfo));
helper.LastTokenRequired();
return pointd;
}
public static float DistanceSquared(Point3D p1, Point3D p2)
{
return (p1 - p2).LengthSquared();
}
public static float Distance(Point3D p1, Point3D p2)
{
return (p1 - p2).Length();
}
public VertexPositionNormalTexture(Point3D position, Vector3D normal, Point2D textureCoordinate)
{
Position = position;
Normal = normal;
TextureCoordinate = textureCoordinate;
}
public Camera(Point3D position, Vector3D up, Vector3D forward)
{
Position = position;
Up = up;
Forward = forward;
}
//
// Compute scene vertex normals
//
public void computeNormals(Scene3ds scene, Scene result)
{
Point3D vcenter = Point3D.Zero;
float vcounter = 0.0f;
for (int i = 0; i < scene.Meshes.Count(); i++)
{
Mesh3ds m = scene.Meshes.ElementAt(i);
// Alloc memory
Mesh mesh = new Mesh
{
Name = m.Name
};
result.Meshes.Add(mesh);
//mesh._numTexCoords = 0;
Vector3D[] tmpFaceNormals = new Vector3D[m.faces()];
// Compute face normals
for (int fi = 0; fi < m.faces(); fi++)
{
Face3ds f = m.face(fi);
Vertex3ds p0 = m.vertex(f.P0);
Vertex3ds p1 = m.vertex(f.P1);
Vertex3ds p2 = m.vertex(f.P2);
/*// Compute face middle point
mesh.faceMiddlePoint[fi] = new PVector();
mesh.faceMiddlePoint[fi].x = (p0.X + p1.X + p2.X) / 3.0f;
mesh.faceMiddlePoint[fi].y = (p0.Y + p1.Y + p2.Y) / 3.0f;
mesh.faceMiddlePoint[fi].z = (p0.Z + p1.Z + p2.Z) / 3.0f;*/
Point3D v0 = new Point3D(p0.X, p0.Y, p0.Z);
Point3D v1 = new Point3D(p1.X, p1.Y, p1.Z);
Point3D v2 = new Point3D(p2.X, p2.Y, p2.Z);
Vector3D e0 = v1 - v0;
Vector3D e1 = v2 - v0;
//mesh.faceNormals[fi] = e1.cross(e0);
// save a copy of the unnormalized face normal. used for average vertex normals
tmpFaceNormals[fi] = Vector3D.Cross(e1, e0);
// normalize face normal
//mesh.faceNormals[fi].normalize();
}
//
// Compute vertex normals.Take average from adjacent face normals.find coplanar faces or get weighted normals.
// One could also use the smooth groups from 3ds to compute normals, we'll see about that.
//
//PVector v = new PVector();
TexCoord3ds tc = new TexCoord3ds(0, 0);
for (int vi = 0; vi < m.vertices(); vi++)
{
Vertex3ds p = m.vertex(vi);
vcenter += new Point3D(p.X, p.Y, p.Z);
vcounter++;
if (m.texCoords() > 0) tc = m.texCoord(vi);
Vector3D n = Vector3D.Zero;
float num = 0;
for (int fi = 0; fi < m.faces(); fi++)
{
Face3ds f = m.face(fi);
// Vertex3ds p0 = m.vertex(f.P0);
// Vertex3ds p1 = m.vertex(f.P1);
// Vertex3ds p2 = m.vertex(f.P2);
if (vi == f.P0 || vi == f.P1 || vi == f.P2)
{
num++;
n += tmpFaceNormals[fi]; //mesh.faceNormals[fi] );
}
}
if (num > 0) n *= 1.0f/(float) num;
n.Normalize();
mesh.Normals.Add(n);
if (FLIPYZ)
{
Vector3D tmp = mesh.Normals[vi];
mesh.Normals[vi] = new Vector3D(tmp.X, -tmp.Z, tmp.Y);
}
// Save vertex data
if (FLIPYZ) mesh.Positions.Add(new Point3D(p.X, -p.Z, p.Y));
else mesh.Positions.Add(new Point3D(p.X, p.Y, p.Z));
// Save texcoord data
//mesh._numTexCoords = m.texCoords();
if (m.texCoords() > 0)
{
if (FLIPV) mesh.TextureCoordinates.Add(new Point3D(tc.U, 1.0f - tc.V, 0));
else mesh.TextureCoordinates.Add(new Point3D(tc.U, tc.V, 0));
}
}
}
if (vcounter > 0.0) vcenter /= vcounter;
}
/// <summary>
/// Transforms a Point3D by the given Matrix.
/// </summary>
/// <param name="position">The source Point3D.</param>
/// <param name="matrix">The transformation matrix.</param>
/// <returns>The HomogeneousPoint3D resulting from the transformation.</returns>
public static Point4D Transform(Point3D position, Matrix3D matrix)
{
Point4D result;
result.X = (((position.X * matrix.M11) + (position.Y * matrix.M21)) + (position.Z * matrix.M31)) + matrix.M41;
result.Y = (((position.X * matrix.M12) + (position.Y * matrix.M22)) + (position.Z * matrix.M32)) + matrix.M42;
result.Z = (((position.X * matrix.M13) + (position.Y * matrix.M23)) + (position.Z * matrix.M33)) + matrix.M43;
result.W = (((position.X * matrix.M14) + (position.Y * matrix.M24)) + (position.Z * matrix.M34)) + matrix.M44;
return result;
}
public static void Subtract(ref Point3D value1, ref Point3D value2, out Vector3D result)
{
result = new Vector3D(value1.X - value2.X, value1.Y - value2.Y, value1.Z - value2.Z);
}
/// <summary>
/// Performs a cubic bezier interpolation between four Point3D control
/// points, returning the value at the specified time (t ranges 0 to 1).
/// </summary>
private static Point3D Bezier(Point3D p1, Point3D p2, Point3D p3, Point3D p4, float t)
{
Point3D result = new Point3D();
result.X = Bezier(p1.X, p2.X, p3.X, p4.X, t);
result.Y = Bezier(p1.Y, p2.Y, p3.Y, p4.Y, t);
result.Z = Bezier(p1.Z, p2.Z, p3.Z, p4.Z, t);
return result;
}
public static Point3D Transform(Point3D position, Matrix3D matrix)
{
Point3D vector;
float num3 = (((position.X * matrix.M11) + (position.Y * matrix.M21)) + (position.Z * matrix.M31)) + matrix.M41;
float num2 = (((position.X * matrix.M12) + (position.Y * matrix.M22)) + (position.Z * matrix.M32)) + matrix.M42;
float num = (((position.X * matrix.M13) + (position.Y * matrix.M23)) + (position.Z * matrix.M33)) + matrix.M43;
vector.X = num3;
vector.Y = num2;
vector.Z = num;
return vector;
}
/// <summary>
/// Creates vertices for a patch that is tessellated at the specified level.
/// </summary>
protected void CreatePatchVertices(Point3D[] patch, bool isMirrored)
{
Debug.Assert(patch.Length == 16);
for (int i = 0; i <= TessellationLevel; i++)
{
float ti = (float)i / TessellationLevel;
for (int j = 0; j <= TessellationLevel; j++)
{
float tj = (float)j / TessellationLevel;
// Perform four horizontal bezier interpolations
// between the control points of this patch.
Point3D p1 = Bezier(patch[0], patch[1], patch[2], patch[3], ti);
Point3D p2 = Bezier(patch[4], patch[5], patch[6], patch[7], ti);
Point3D p3 = Bezier(patch[8], patch[9], patch[10], patch[11], ti);
Point3D p4 = Bezier(patch[12], patch[13], patch[14], patch[15], ti);
// Perform a vertical interpolation between the results of the
// previous horizontal interpolations, to compute the position.
Point3D position = Bezier(p1, p2, p3, p4, tj);
// Perform another four bezier interpolations between the control
// points, but this time vertically rather than horizontally.
Point3D q1 = Bezier(patch[0], patch[4], patch[8], patch[12], tj);
Point3D q2 = Bezier(patch[1], patch[5], patch[9], patch[13], tj);
Point3D q3 = Bezier(patch[2], patch[6], patch[10], patch[14], tj);
Point3D q4 = Bezier(patch[3], patch[7], patch[11], patch[15], tj);
// Compute vertical and horizontal tangent vectors.
Vector3D tangentA = BezierTangent(p1, p2, p3, p4, tj);
Vector3D tangentB = BezierTangent(q1, q2, q3, q4, ti);
// Cross the two tangent vectors to compute the normal.
Vector3D normal = Vector3D.Cross(tangentA, tangentB);
if (normal.Length() > 0.0001f)
{
normal.Normalize();
// If this patch is mirrored, we must invert the normal.
if (isMirrored)
normal = -normal;
}
else
{
// In a tidy and well constructed bezier patch, the preceding
// normal computation will always work. But the classic teapot
// model is not tidy or well constructed! At the top and bottom
// of the teapot, it contains degenerate geometry where a patch
// has several control points in the same place, which causes
// the tangent computation to fail and produce a zero normal.
// We 'fix' these cases by just hard-coding a normal that points
// either straight up or straight down, depending on whether we
// are on the top or bottom of the teapot. This is not a robust
// solution for all possible degenerate bezier patches, but hey,
// it's good enough to make the teapot work correctly!
if (position.Y > 0)
normal = Vector3D.Up;
else
normal = Vector3D.Down;
}
// Create the vertex.
AddVertex(position, normal);
}
}
}
public static void SetPoint3D(string key, Point3D value)
{
SetFloats(key, new []{value.X, value.Y, value.Z});
}
public ParticleAnchoredBungee(Particle particle, Point3D anchor, float springConstant, float restLength)
: base(particle, anchor, springConstant, restLength)
{
}
protected void AddVertex(Point3D position, Vector3D normal)
{
Positions.Add(position + PositionOffset);
Normals.Add(normal);
}
