internal void recalcArrowHead(ArrowHeadShape ah, PointF pt1, PointF pt2)
{
float dx = pt2.X - pt1.X;
float dy = pt2.Y - pt1.Y;
float l = (float)Math.Sqrt(dx * dx + dy * dy);
if (l == 0)
{
ah.defined = false;
return;
}
ah.defined = true;
float sine = +dx / l;
float cosine = -dy / l;
int pts, c = 0, ch = 0;
float x, y, r;
for (int i = 0; i < elements.Count; ++i)
{
EArrowHeadElement el = (EArrowHeadElement)elements[i];
switch (el)
{
case EArrowHeadElement.heLine:
for (int j = 0; j < 2; ++j)
{
x = (float)coords[c++] * ah.size;
y = (float)coords[c++] * ah.size;
ah.coords[ch++] = x * cosine - y * sine + pt2.X;
ah.coords[ch++] = x * sine + y * cosine + pt2.Y;
}
break;
case EArrowHeadElement.heShape:
pts = (int)elements[++i];
for (int j = 0; j < pts; ++j)
{
x = (float)coords[c++] * ah.size;
y = (float)coords[c++] * ah.size;
ah.coords[ch++] = x * cosine - y * sine + pt2.X;
ah.coords[ch++] = x * sine + y * cosine + pt2.Y;
}
break;
case EArrowHeadElement.heCircle:
x = (float)coords[c++] * ah.size;
y = (float)coords[c++] * ah.size;
r = (float)coords[c++] * ah.size;
ah.coords[ch++] = x * cosine - y * sine + pt2.X;
ah.coords[ch++] = x * sine + y * cosine + pt2.Y;
ah.coords[ch++] = r;
break;
} // switch (el)
} // for (
}
internal void draw(Graphics g, System.Drawing.Pen pen,
System.Drawing.Brush brush, float xoff, float yoff)
{
if (!defined)
{
return;
}
int c = 0;
for (int i = 0; i < elements.GetLength(0); ++i)
{
EArrowHeadElement el = (EArrowHeadElement)elements[i];
switch (el)
{
case EArrowHeadElement.heLine:
{
float x1 = coords[c++] + xoff;
float y1 = coords[c++] + yoff;
float x2 = coords[c++] + xoff;
float y2 = coords[c++] + yoff;
g.DrawLine(pen, new PointF(x1, y1), new PointF(x2, y2));
}
break;
case EArrowHeadElement.heShape:
{
int pts = elements[++i];
PointF[] shape = new PointF[pts];
for (int j = 0; j < pts; ++j)
{
shape[j].X = coords[c++] + xoff;
shape[j].Y = coords[c++] + yoff;
}
g.FillPolygon(brush, shape);
g.DrawPolygon(pen, shape);
}
break;
case EArrowHeadElement.heCircle:
{
float cx = coords[c++] + xoff;
float cy = coords[c++] + yoff;
float r = coords[c++];
g.FillEllipse(brush, cx - r, cy - r, 2 * r, 2 * r);
g.DrawEllipse(pen, cx - r, cy - r, 2 * r, 2 * r);
}
break;
} // switch (el)
}
}
