/// <summary>
/// Угол между векторами
/// </summary>
public static double Angle(Vector a, Vector b, double epsilon)
{
double q = Math.Asin(CrossProduct(a, b) / (a.Length * b.Length));
if (a.Length < epsilon || b.Length < epsilon)
throw new ZeroVectorsAngleException("Trying to find angle between zero-length vectors (epsilon = " + epsilon + ")");
else
return q;
}
/// <summary>
/// Векторное произведение
/// </summary>
public static double CrossProduct(Vector a, Vector b)
{
return a.m_x * b.m_y - a.m_y * b.m_x;
}
public static Point GetCrossing(Segment s1, Segment s2)
{
// Algorithmic equality
if (s1 == s2)
throw new SelfCrossingException("Trying to find selfcrossing");
// TODO: Add rough estimation here (i.e. rectangle estimation)
if (s1._Crossings.ContainsKey(s2))
return s1._Crossings[s2];
// TODO: Check integrity
// Parallelism and zero-length
Vector AB1 = new Vector(s1._B.X - s1._A.X, s1._B.Y - s1._A.Y);
Vector AB2 = new Vector(s2._B.X - s2._A.X, s2._B.Y - s2._A.Y);
double D = Vector.CrossProduct(AB2, AB1);
if (Math.Abs(D) == 0) return null;
if (s1._A == s2._A || s1._A == s2._B) return s1._A;
if (s1._B == s2._A || s1._B == s2._B) return s1._B;
// Calculating crossing between lines
double m = Vector.CrossProduct((Vector)s1._A, AB1);
double n = Vector.CrossProduct((Vector)s2._A, AB2);
double x = (m * AB2.X - n * AB1.X) / D;
double y = (m * AB2.Y - n * AB1.Y) / D;
// Checking if an endpoint of one segment is contained by other
if (s1._A.X == x && s1._A.Y == y) return s1._A;
if (s1._B.X == x && s1._B.Y == y) return s1._B;
if (s2._A.X == x && s2._A.Y == y) return s2._A;
if (s2._B.X == x && s2._B.Y == y) return s2._B;
// Checking if the crossing point is in both segments
Vector AC1 = new Vector(x - s1._A.X, y - s1._A.Y);
Vector BC1 = new Vector(x - s1._B.X, y - s1._B.Y);
if ((AB1 * AC1) * (-AB1 * BC1) < 0) return null;
Vector AC2 = new Vector(x - s2._A.X, y - s2._A.Y);
Vector BC2 = new Vector(x - s2._B.X, y - s2._B.Y);
if ((AB2 * AC2) * (-AB2 * BC2) < 0) return null;
// Adding the point to crossing dictionaries
Point crs = new Point(x, y);
s1._Crossings.Add(s2, crs);
s2._Crossings.Add(s1, crs);
return crs;
}
public static Point Move(Point p, Vector v)
{
return new Point(p._X + v.X, p._Y + v.Y);
}
public double GetArea()
{
double res = 0;
for (int i = 1; i < mVertex.Length - 1; i++)
{
Vector a = new Vector(mVertex[i].X - mVertex[0].X,
mVertex[i].Y - mVertex[0].Y);
Vector b = new Vector(mVertex[i + 1].X - mVertex[0].X,
mVertex[i + 1].Y - mVertex[0].Y);
res += Vector.CrossProduct(a, b);
}
res /= 2;
return res;
}
public bool Contains(Point p)
{
Vector a0 = new Vector(
mVertex[0].X - mVertex[mVertex.Length - 1].X,
mVertex[0].Y - mVertex[mVertex.Length - 1].Y);
Vector b0 = new Vector(
p.X - mVertex[mVertex.Length - 1].X,
p.Y - mVertex[mVertex.Length - 1].Y);
if (Vector.CrossProduct(a0, b0) <= 0) return false;
for (int i = 1; i < mVertex.Length; i++)
{
Vector a = new Vector(
mVertex[i].X - mVertex[i - 1].X,
mVertex[i].Y - mVertex[i - 1].Y);
Vector b = new Vector(
p.X - mVertex[i - 1].X,
p.Y - mVertex[i - 1].Y);
if (Vector.CrossProduct(a, b) <= 0) return false;
}
return true;
}
public override bool ReportMousePosition(int x, int y, int width, int height)
{
if (width == 0 || height == 0) return false;
CrotateStageOperationParameters pm = ((CrotateStageOperationParameters)Parameters);
bool res = false;
if (mDragState == DragState.Center)
{
int new_scr_x = mCenterDotStartX - mDragStartX + x;
int new_scr_y = mCenterDotStartY - mDragStartY + y;
pm.Center = new Point((double)new_scr_x / width, (double)new_scr_y / height);
res = true;
}
else if (mDragState == DragState.Round)
{
Point scr_C = new Point(width * pm.Center.X, height * pm.Center.Y);
Point cur = new Point(x, y);
Vector cur_dir = new Vector(scr_C, cur);
pm.Angle = 180.0 / Math.PI * Math.Atan2(cur_dir.Y, cur_dir.X);
res = true;
}
else if (mDragState == DragState.Corner)
{
Point scr_C = new Point(width * pm.Center.X, height * pm.Center.Y);
Point scr_cur = new Point(x, y);
Point scr_rnd = new Point(
(scr_C.X + (rt_corner_rot.X + rb_corner_rot.X) / 2),
(scr_C.Y + (rt_corner_rot.Y + rb_corner_rot.Y) / 2));
Point scr_start = new Point(mDragStartX, mDragStartY);
// Rotated orts
Vector v_w = new Vector(scr_C, scr_rnd);
v_w /= v_w.Length;
Vector v_h = new Vector(v_w.Y, -v_w.X);
// Current diameter
Vector D = new Vector(scr_C, scr_cur);
double Dw = D * v_w;
double Dh = D * v_h;
// Starting diameter
Vector D0 = new Vector(scr_C, scr_start);
double D0w = D0 * v_w;
double D0h = D0 * v_h;
switch (pm.Mode)
{
case CatEye.Core.CrotateStageOperation.Mode.Disproportional:
pm.CropWidth = mCropWidthStart * Dw / D0w;
pm.CropHeight = mCropHeightStart * Dh / D0h;
break;
case CatEye.Core.CrotateStageOperation.Mode.ProportionalWidthFixed:
pm.CropWidth = mCropWidthStart * Dw / D0w;
break;
case CatEye.Core.CrotateStageOperation.Mode.ProportionalHeightFixed:
pm.CropHeight = mCropHeightStart * Dh / D0h;
break;
}
res = true;
}
return res;
}