void update_from_endpoints(Vector2d p0, Vector2d p1)
{
Center = 0.5 * (p0 + p1);
Direction = p1 - p0;
Extent = 0.5 * Direction.Normalize();
}
public Segment2d(Vector2d center, Vector2d direction, double extent)
{
Center = center; Direction = direction; Extent = extent;
}
public double Project(Vector2d p)
{
return((p - Center).Dot(Direction));
}
public double Distance(Vector2d pt)
{
double d = Center.Distance(pt);
return(Math.Abs(d - Radius));
}
public void Transform(ITransform2 xform)
{
Center = xform.TransformP(Center);
Radius = xform.TransformScalar(Radius);
}
public void Simplify(double clusterTol = 0.0001,
double lineDeviationTol = 0.01,
bool bSimplifyStraightLines = true)
{
int n = vertices.Count;
if (n < 3)
{
return;
}
int i, k, pv; // misc counters
Vector2d[] vt = new Vector2d[n + 1]; // vertex buffer
bool[] mk = new bool[n + 1];
for (i = 0; i < n + 1; ++i) // marker buffer
{
mk[i] = false;
}
// STAGE 1. Vertex Reduction within tolerance of prior vertex cluster
double clusterTol2 = clusterTol * clusterTol;
vt[0] = vertices[0]; // start at the beginning
for (i = 1, k = 1, pv = 0; i < n; i++)
{
if ((vertices[i] - vertices[pv]).LengthSquared < clusterTol2)
{
continue;
}
vt[k++] = vertices[i];
pv = i;
}
bool skip_dp = false;
if (k == 1)
{
vt[k++] = vertices[1];
vt[k++] = vertices[2];
skip_dp = true;
}
else if (k == 2)
{
vt[k++] = vertices[0];
skip_dp = true;
}
// push on start vertex again, because simplifyDP is for polylines, not polygons
vt[k++] = vertices[0];
// STAGE 2. Douglas-Peucker polyline simplification
int nv = 0;
if (skip_dp == false && lineDeviationTol > 0)
{
mk[0] = mk[k - 1] = true; // mark the first and last vertices
simplifyDP(lineDeviationTol, vt, 0, k - 1, mk);
for (i = 0; i < k - 1; ++i)
{
if (mk[i])
{
nv++;
}
}
}
else
{
for (i = 0; i < k; ++i)
{
mk[i] = true;
}
nv = k - 1;
}
// polygon requires at least 3 vertices
if (nv == 2)
{
for (i = 1; i < k - 1; ++i)
{
if (mk[1] == false)
{
mk[1] = true;
}
else if (mk[k - 2] == false)
{
mk[k - 2] = true;
}
}
nv++;
}
else if (nv == 1)
{
mk[1] = true;
mk[2] = true;
nv += 2;
}
// copy marked vertices back to this polygon
vertices = new List <Vector2d>();
for (i = 0; i < k - 1; ++i) // last vtx is copy of first, and definitely marked
{
if (mk[i])
{
vertices.Add(vt[i]);
}
}
Timestamp++;
return;
}
public double SignedDistance(Vector2d pt)
{
double d = Center.Distance(pt);
return(d - Radius);
}
public Vector3d(Vector2d copy, double _z)
{
x = copy.x; y = copy.y; z = _z;
}
public bool IsReversed; // use ccw orientation instead of cw
public Circle2d(Vector2d center, double radius)
{
IsReversed = false;
Center = center;
Radius = radius;
}
override public MeshGenerator Generate()
{
if (Polygon == null)
{
Polygon = Polygon2d.MakeCircle(1.0f, 8);
}
int Slices = Polygon.VertexCount;
int nRings = Vertices.Count;
int nRingSize = (NoSharedVertices) ? Slices + 1 : Slices;
int nCapVertices = (NoSharedVertices) ? Slices + 1 : 1;
if (Capped == false)
{
nCapVertices = 0;
}
vertices = new VectorArray3d(nRings * nRingSize + 2 * nCapVertices);
uv = new VectorArray2f(vertices.Count);
normals = new VectorArray3f(vertices.Count);
int nSpanTris = (Vertices.Count - 1) * (2 * Slices);
int nCapTris = (Capped) ? 2 * Slices : 0;
triangles = new IndexArray3i(nSpanTris + nCapTris);
Frame3f fCur = new Frame3f(Frame);
Vector3d dv = CurveUtils.GetTangent(Vertices, 0);;
fCur.Origin = (Vector3f)Vertices[0];
fCur.AlignAxis(2, (Vector3f)dv);
Frame3f fStart = new Frame3f(fCur);
// generate tube
for (int ri = 0; ri < nRings; ++ri)
{
// propagate frame
if (ri != 0)
{
Vector3d tan = CurveUtils.GetTangent(Vertices, ri);
fCur.Origin = (Vector3f)Vertices[ri];
if (ri == 11)
{
dv = tan;
}
fCur.AlignAxis(2, (Vector3f)tan);
}
float uv_along = (float)ri / (float)(nRings - 1);
// generate vertices
int nStartR = ri * nRingSize;
for (int j = 0; j < nRingSize; ++j)
{
float uv_around = (float)j / (float)(nRings);
int k = nStartR + j;
Vector2d pv = Polygon.Vertices[j % Slices];
Vector3d v = fCur.FromPlaneUV((Vector2f)pv, 2);
vertices[k] = v;
uv[k] = new Vector2f(uv_along, uv_around);
Vector3f n = (Vector3f)(v - fCur.Origin).Normalized;
normals[k] = n;
}
}
// generate triangles
int ti = 0;
for (int ri = 0; ri < nRings - 1; ++ri)
{
int r0 = ri * nRingSize;
int r1 = r0 + nRingSize;
for (int k = 0; k < nRingSize - 1; ++k)
{
triangles.Set(ti++, r0 + k, r0 + k + 1, r1 + k + 1, Clockwise);
triangles.Set(ti++, r0 + k, r1 + k + 1, r1 + k, Clockwise);
}
if (NoSharedVertices == false) // close disc if we went all the way
{
triangles.Set(ti++, r1 - 1, r0, r1, Clockwise);
triangles.Set(ti++, r1 - 1, r1, r1 + nRingSize - 1, Clockwise);
}
}
if (Capped)
{
// add endcap verts
int nBottomC = nRings * nRingSize;
vertices[nBottomC] = fStart.Origin;
uv[nBottomC] = new Vector2f(0.5f, 0.5f);
normals[nBottomC] = -fStart.Z;
startCapCenterIndex = nBottomC;
int nTopC = nBottomC + 1;
vertices[nTopC] = fCur.Origin;
uv[nTopC] = new Vector2f(0.5f, 0.5f);
normals[nTopC] = fCur.Z;
endCapCenterIndex = nTopC;
if (NoSharedVertices)
{
// duplicate first loop and make a fan w/ bottom-center
int nExistingB = 0;
int nStartB = nTopC + 1;
for (int k = 0; k < Slices; ++k)
{
vertices[nStartB + k] = vertices[nExistingB + k];
uv[nStartB + k] = (Vector2f)Polygon.Vertices[k].Normalized;
normals[nStartB + k] = normals[nBottomC];
}
append_disc(Slices, nBottomC, nStartB, true, Clockwise, ref ti);
// duplicate second loop and make fan
int nExistingT = nRingSize * (nRings - 1);
int nStartT = nStartB + Slices;
for (int k = 0; k < Slices; ++k)
{
vertices[nStartT + k] = vertices[nExistingT + k];
uv[nStartT + k] = (Vector2f)Polygon.Vertices[k].Normalized;
normals[nStartT + k] = normals[nTopC];
}
append_disc(Slices, nTopC, nStartT, true, !Clockwise, ref ti);
}
else
{
append_disc(Slices, nBottomC, 0, true, Clockwise, ref ti);
append_disc(Slices, nTopC, nRingSize * (nRings - 1), true, !Clockwise, ref ti);
}
}
return(this);
}
public Ray2d(Vector2d origin, Vector2d direction)
{
this.Origin = origin;
this.Direction = direction;
this.Direction.Normalize(); // float cast may not be normalized in double, is trouble in algorithms!
}
/// <summary>
/// hex-grid tiling of circles inside bounds, with spacing between elements
/// Returns list of translations to element.
/// Always allows at least one row and column, even if element overflows bounds in that dimension.
/// </summary>
public static List <Vector2d> BoundedCircleTiling2(AxisAlignedBox2d element, AxisAlignedBox2d bounds,
double spacing)
{
Vector2d oshift = -element.Min;
double w = element.Width; double h = element.Height;
if (MathUtil.EpsilonEqual(w, h, MathUtil.Epsilonf) == false)
{
throw new Exception("BoundedHexTiling2: input box is not square");
}
// note: this is a circle tiling, not a hex tiling, so even though we are
// starting in top-left with a "tip" hex, we don't have to offset down so that tip is inside
// the box (circle cuts off)
double r = w / 2;
Hexagon2d hex = new Hexagon2d(element.Center, r, Hexagon2d.TopModes.Tip);
hex.InnerRadius = r;
double stepx = hex.HorzSpacing;
double stepy = hex.VertSpacing;
double spacingy = spacing;
double spacingx = spacing;
// half-rows on top and bottom add up to full row-height
int ny = Math.Max(1, (int)(bounds.Height / stepy));
// reduce count so that we fit w/ spacing
double spaceh = (ny - 1) * spacingy;
while (ny > 1 && bounds.Height - (stepy * ny + spaceh) < 0)
{
ny--;
}
// even rows start at x=0
int nx_even = Math.Max(1, (int)(bounds.Width / stepx));
// reduce count if we spill over w/ spacing
double spacew = (nx_even - 1) * spacingx;
while (nx_even > 1 && bounds.Width - (stepx * nx_even + spacew) < 0)
{
nx_even--;
}
// odd rows have an extra half-step added to left side,
// so we may need to reduce count
int nx_odd = nx_even;
spacew = (nx_odd - 1) * spacingx;
if (ny > 0 && (stepx * nx_odd + spacew + stepx * 0.5) > bounds.Width)
{
nx_odd--;
spacew = (nx_odd - 1) * spacingx;
}
List <Vector2d> translations = new List <Vector2d>();
for (int yi = 0; yi < ny; ++yi)
{
double dy = yi * stepy + yi * spacingy;
// x shift and count are different on odd rows
double shiftx = stepx * 0.5;
int nx = nx_odd;
if (yi % 2 == 0)
{
shiftx = 0;
nx = nx_even;
}
for (int xi = 0; xi < nx; ++xi)
{
double dx = shiftx + xi * stepx + xi * spacingx;
translations.Add(new Vector2d(dx, dy) + oshift + bounds.Min);
}
}
return(translations);
}
public void AppendVertex(Vector2d v)
{
vertices.Add(v);
Timestamp++;
}
public void Chamfer(double chamfer_dist, double minConvexAngleDeg = 30, double minConcaveAngleDeg = 30)
{
if (IsClockwise)
{
throw new Exception("must be ccw?");
}
List <Vector2d> NewV = new List <Vector2d>();
int N = Vertices.Count;
int iCur = 0;
do
{
Vector2d center = Vertices[iCur];
int iPrev = (iCur == 0) ? N - 1 : iCur - 1;
Vector2d prev = Vertices[iPrev];
int iNext = (iCur + 1) % N;
Vector2d next = Vertices[iNext];
Vector2d cp = prev - center;
double cpdist = cp.Normalize();
Vector2d cn = next - center;
double cndist = cn.Normalize();
// if degenerate, skip this vert
if (cpdist < MathUtil.ZeroTolerancef || cndist < MathUtil.ZeroTolerancef)
{
iCur = iNext;
continue;
}
double angle = Vector2d.AngleD(cp, cn);
// TODO document what this means sign-wise
double sign = cp.Perp.Dot(cn);
bool bConcave = (sign > 0);
double thresh = (bConcave) ? minConcaveAngleDeg : minConvexAngleDeg;
// ok not too sharp
if (angle > thresh)
{
NewV.Add(center);
iCur = iNext;
continue;
}
double prev_cut_dist = Math.Min(chamfer_dist, cpdist * 0.5);
Vector2d prev_cut = center + prev_cut_dist * cp;
double next_cut_dist = Math.Min(chamfer_dist, cndist * 0.5);
Vector2d next_cut = center + next_cut_dist * cn;
NewV.Add(prev_cut);
NewV.Add(next_cut);
iCur = iNext;
} while (iCur != 0);
vertices = NewV;
Timestamp++;
}
public static double IsLeft(ref Vector2d P0, ref Vector2d P1, ref Vector2d P2)
{
return(Math.Sign(((P1.x - P0.x) * (P2.y - P0.y) - (P2.x - P0.x) * (P1.y - P0.y))));
}
public bool Contains(Vector2d p)
{
double d = Center.DistanceSquared(p);
return(d <= Radius * Radius);
}
/// <summary>
/// Compute barycentric coordinates/weights of vPoint inside triangle (V0,V1,V2).
/// If point is inside triangle, coords will pe positive and sum to 1.
/// ie if result is a, then vPoint = a.x*V0 + a.y*V1 + a.z*V2.
/// </summary>
public static Vector3d BarycentricCoords(Vector2d vPoint, Vector2d V0, Vector2d V1, Vector2d V2)
{
Vector2d kV02 = V0 - V2;
Vector2d kV12 = V1 - V2;
Vector2d kPV2 = vPoint - V2;
double fM00 = kV02.Dot(kV02);
double fM01 = kV02.Dot(kV12);
double fM11 = kV12.Dot(kV12);
double fR0 = kV02.Dot(kPV2);
double fR1 = kV12.Dot(kPV2);
double fDet = fM00 * fM11 - fM01 * fM01;
double fInvDet = 1.0 / fDet;
double fBary1 = (fM11 * fR0 - fM01 * fR1) * fInvDet;
double fBary2 = (fM00 * fR1 - fM01 * fR0) * fInvDet;
double fBary3 = 1.0 - fBary1 - fBary2;
return(new Vector3d(fBary1, fBary2, fBary3));
}
public double DistanceSquared(Vector2d p)
{
int seg; double segt;
return(DistanceSquared(p, out seg, out segt));
}
