public Vertex(Point xiPosition, Vector xiNormal, Color xiColor, int xiTexCoordX, int xiTexCoordY)
{
mPosition = xiPosition;
mNormal = xiNormal;
mColor = xiColor;
mTexCoordX = xiTexCoordX;
mTexCoordY = xiTexCoordY;
}
public void testDecomposition()
{
Matrix t = Matrix.Translation(9, 10, 11);
Vector rotAxis = new Vector(1, 2, 3).Normalise();
// == [0.26726, 0.5345, 0.801]
Matrix r = Matrix.Rotation(1.5, rotAxis);
Matrix s = Matrix.ScalingMatrix(3, 3, 3);
Matrix m = s*r*t;
Vector scale;
Vector rotationAxis;
double rotationAngle;
Vector translation;
m.Decompose(out translation, out rotationAxis, out rotationAngle, out scale);
Assert.AreEqual(new Vector(9, 10, 11), translation);
Assert.AreEqual(rotAxis, rotationAxis * -1); // TODO need to fix rotation inverse
Assert.That(1.5, AlmostEqualTo(rotationAngle));
Assert.AreEqual(new Vector(3,3,3), scale);
testDecompositionRoundTrip(m);
}
// a 2d move request, which will be turned into 3d camera
// movement, in a manner dependent on
private void MoveCamera(Vector xiMove)
{
if (MovementMode == eMovementMode.InspectMode)
{
//turn movement requests into rotation about origin
}
if (LightingMode == eLightingMode.Headlight)
{
//light moves with camera
mLight.Move(xiMove);
}
mCamera.Move(xiMove);
}
public double Dot(Vector xiOther)
{
return mElements[0] * xiOther.mElements[0]
+ mElements[1] * xiOther.mElements[1]
+ mElements[2] * xiOther.mElements[2];
}
/// <summary>
/// TODO: document this method...
///
/// Not 100% sure what this does -- it came from the GLTK code.
/// I think it keeps the rotations the same but makes them more 'normalised'?
/// </summary>
public Matrix Orthogonalise()
{
Vector lColumn1 = new Vector(this[1, 0], this[1, 1], this[1, 2]);
Vector lColumn2 = new Vector(this[2, 0], this[2, 1], this[2, 2]);
Vector lNewColumn0 = (lColumn1 ^ lColumn2).Normalise();
Vector lNewColumn1 = lColumn1.Normalise();
Vector lNewColumn2 = (lNewColumn0 ^ lColumn1).Normalise();
return new Matrix(
lNewColumn0.x, lNewColumn0.y, lNewColumn0.z, 0,
lNewColumn1.x, lNewColumn1.y, lNewColumn1.z, 0,
lNewColumn2.x, lNewColumn2.y, lNewColumn2.z, 0,
this[3, 0], this[3, 1], this[3, 2], this[3, 3]);
}
/// <summary>
/// If possible, decomposes this matrix into S*R*T
/// for a translation T, a rotation R and a scaling S.
///
/// The rotation is represented as an angle in radians about an axis.
///
/// http://graphcomp.com/info/specs/sgi/vrml/spec/part1/concepts.html#CoordinateSystems
/// http://graphcomp.com/info/specs/sgi/vrml/spec/part1/nodesRef.html#Transform
/// </summary>
public void Decompose(out Vector translation, out Vector rotationAxis, out double rotationAngle, out Vector scale)
{
translation = new Vector(this[3, 0], this[3, 1], this[3, 2]);
var M11 = this[0, 0];
var M12 = this[0, 1];
var M13 = this[0, 2];
var M14 = this[0, 3];
var M21 = this[1, 0];
var M22 = this[1, 1];
var M23 = this[1, 2];
var M24 = this[1, 3];
var M31 = this[2, 0];
var M32 = this[2, 1];
var M33 = this[2, 2];
var M34 = this[2, 3];
var M41 = this[3, 0];
var M42 = this[3, 1];
var M43 = this[3, 2];
float xs = (Math.Sign(M11 * M12 * M13 * M14) < 0) ? -1f : 1f;
float ys = (Math.Sign(M21 * M22 * M23 * M24) < 0) ? -1f : 1f;
float zs = (Math.Sign(M31 * M32 * M33 * M34) < 0) ? -1f : 1f;
var scaleX = xs * (float)Math.Sqrt(M11 * M11 + M12 * M12 + M13 * M13);
var scaleY = ys * (float)Math.Sqrt(M21 * M21 + M22 * M22 + M23 * M23);
var scaleZ = zs * (float)Math.Sqrt(M31 * M31 + M32 * M32 + M33 * M33);
scale = new Vector(scaleX,scaleY,scaleZ);
if (scaleX == 0.0 || scaleY == 0.0 || scaleZ == 0.0)
{
rotationAngle = 0;
rotationAxis = new Vector(1, 0, 0);
return;
}
Matrix m1 = new Matrix(M11 / scaleX, M12 / scaleX, M13 / scaleX, 0,
M21 / scaleY, M22 / scaleY, M23 / scaleY, 0,
M31 / scaleZ, M32 / scaleZ, M33 / scaleZ, 0,
0, 0, 0, 1);
var rotation = Quaternion.CreateFromRotationMatrix(m1);
rotation.ToAxisAngle(out rotationAxis, out rotationAngle);
}
public static Matrix Translation(Vector xiVector)
{
return Translation(xiVector.x, xiVector.y, xiVector.z);
}
public static Matrix Rotation(double xiAngle, Vector xiAxis)
{
if (xiAxis.Length == 0)
{
throw new Exception("Cannot have axis of zero length");
}
double t = 1 - Math.Cos(xiAngle);
double s = Math.Sin(xiAngle);
double c = Math.Cos(xiAngle);
double x = xiAxis.x / xiAxis.Length;
double y = xiAxis.y / xiAxis.Length;
double z = xiAxis.z / xiAxis.Length;
return new Matrix(
t * x * x + c, t * x * y - s * z, t * x * z + s * y, 0,
t * x * y + s * z, t * y * y + c, t * y * z - s * x, 0,
t * x * z - s * y, t * y * z + s * x, t * z * z + c, 0,
0, 0, 0, 1);
}
public void LookAt(Point xiTarget, Vector xiUp)
{
Vector lV1 = (Position - xiTarget).Normalise();
Vector lV2 = xiUp.Normalise();
Vector lV3 = lV2 ^ lV1;
lV2 = lV1 ^ lV3;
mTransform = new Matrix(
lV3.x, lV3.y, lV3.z, 0,
lV2.x, lV2.y, lV2.z, 0,
lV1.x, lV1.y, lV1.z, 0,
mTransform[3, 0], mTransform[3, 1], mTransform[3, 2], mTransform[3, 3]);
Reorthogonalise();
}
public void RotateAboutWorldOrigin(double xiAngle, Vector xiAxis)
{
mTransform = mTransform * Matrix.Rotation(xiAngle, xiAxis);
Reorthogonalise();
}
//rotates about the Entity's current origin.
public void Rotate(double xiAngle, Vector xiAxis)
{
Point lStart = Position;
Position = Point.Origin;
RotateAboutWorldOrigin(xiAngle, xiAxis);
Position = lStart;
}
public void Move(Vector xiVector)
{
mTransform = mTransform * Matrix.Translation(xiVector);
Reorthogonalise();
}
public Vertex(Point xiPosition, Vector xiNormal, Color xiColor)
{
mPosition = xiPosition;
mNormal = xiNormal;
mColor = xiColor;
}