void _addArcCommands(
float cx, float cy, float r, float a0, float a1,
PathWinding dir, bool forceMoveTo, Matrix3 transform = null)
{
// Clamp angles
float da = a1 - a0;
if (dir == PathWinding.clockwise)
{
if (Mathf.Abs(da) >= Mathf.PI * 2)
{
da = Mathf.PI * 2;
}
else
{
while (da < 0.0f)
{
da += Mathf.PI * 2;
}
if (da <= 1e-5)
{
return;
}
}
}
else
{
if (Mathf.Abs(da) >= Mathf.PI * 2)
{
da = -Mathf.PI * 2;
}
else
{
while (da > 0.0f)
{
da -= Mathf.PI * 2;
}
if (da >= -1e-5)
{
return;
}
}
}
// Split arc into max 90 degree segments.
int ndivs = Mathf.Max(1, Mathf.Min((int)(Mathf.Abs(da) / (Mathf.PI * 0.5f) + 0.5f), 5));
float hda = (da / ndivs) / 2.0f;
float kappa = Mathf.Abs(4.0f / 3.0f * (1.0f - Mathf.Cos(hda)) / Mathf.Sin(hda));
if (dir == PathWinding.counterClockwise)
{
kappa = -kappa;
}
PathCommand move = (forceMoveTo || this._commands.Count == 0) ? PathCommand.moveTo : PathCommand.lineTo;
float px = 0, py = 0, ptanx = 0, ptany = 0;
for (int i = 0; i <= ndivs; i++)
{
float a = a0 + da * (i / (float)ndivs);
float dx = Mathf.Cos(a);
float dy = Mathf.Sin(a);
float x = cx + dx * r;
float y = cy + dy * r;
float tanx = -dy * r * kappa;
float tany = dx * r * kappa;
if (i == 0)
{
float x1 = x, y1 = y;
if (transform != null)
{
transform.mapXY(x1, y1, out x1, out y1);
}
if (move == PathCommand.moveTo)
{
this._appendMoveTo(x1, y1);
}
else
{
this._appendLineTo(x1, y1);
}
}
else
{
float c1x = px + ptanx;
float c1y = py + ptany;
float c2x = x - tanx;
float c2y = y - tany;
float x1 = x;
float y1 = y;
if (transform != null)
{
transform.mapXY(c1x, c1y, out c1x, out c1y);
transform.mapXY(c2x, c2y, out c2x, out c2y);
transform.mapXY(x1, y1, out x1, out y1);
}
this._appendBezierTo(c1x, c1y, c2x, c2y, x1, y1);
}
px = x;
py = y;
ptanx = tanx;
ptany = tany;
}
}
public void winding(PathWinding dir)
{
this._appendWinding((float)dir);
}
