//----------------------------------------------------------------
public void Begin(double x, double y, int len)
{
// Calculate transformed coordinates at x1,y1
double xt = x;
double yt = y;
_trans_dir.Transform(ref xt, ref yt);
int x1 = AggMath.iround(xt * SUBPIXEL_SCALE);
int y1 = AggMath.iround(yt * SUBPIXEL_SCALE);
double dx;
double dy;
double delta = 1 / (double)SUBPIXEL_SCALE;
// Calculate scale by X at x1,y1
dx = xt + delta;
dy = yt;
_trans_inv.Transform(ref dx, ref dy);
dx -= x;
dy -= y;
int sx1 = (int)AggMath.uround(SUBPIXEL_SCALE / Math.Sqrt(dx * dx + dy * dy)) >> SUBPIXEL_SHIFT;
// Calculate scale by Y at x1,y1
dx = xt;
dy = yt + delta;
_trans_inv.Transform(ref dx, ref dy);
dx -= x;
dy -= y;
int sy1 = (int)AggMath.uround(SUBPIXEL_SCALE / Math.Sqrt(dx * dx + dy * dy)) >> SUBPIXEL_SHIFT;
// Calculate transformed coordinates at x2,y2
x += len;
xt = x;
yt = y;
_trans_dir.Transform(ref xt, ref yt);
int x2 = AggMath.iround(xt * SUBPIXEL_SCALE);
int y2 = AggMath.iround(yt * SUBPIXEL_SCALE);
// Calculate scale by X at x2,y2
dx = xt + delta;
dy = yt;
_trans_inv.Transform(ref dx, ref dy);
dx -= x;
dy -= y;
int sx2 = (int)AggMath.uround(SUBPIXEL_SCALE / Math.Sqrt(dx * dx + dy * dy)) >> SUBPIXEL_SHIFT;
// Calculate scale by Y at x2,y2
dx = xt;
dy = yt + delta;
_trans_inv.Transform(ref dx, ref dy);
dx -= x;
dy -= y;
int sy2 = (int)AggMath.uround(SUBPIXEL_SCALE / Math.Sqrt(dx * dx + dy * dy)) >> SUBPIXEL_SHIFT;
// Initialize the interpolators
_coord_x = new LineInterpolatorDDA2(x1, x2, len);
_coord_y = new LineInterpolatorDDA2(y1, y2, len);
_scale_x = new LineInterpolatorDDA2(sx1, sx2, len);
_scale_y = new LineInterpolatorDDA2(sy1, sy2, len);
}
//--------------------------------------------------------------------
public LineInterpolatorBresenham(int x1, int y1, int x2, int y2)
{
m_x1_lr = (line_lr(x1));
m_y1_lr = (line_lr(y1));
m_x2_lr = (line_lr(x2));
m_y2_lr = (line_lr(y2));
m_ver = (Math.Abs(m_x2_lr - m_x1_lr) < Math.Abs(m_y2_lr - m_y1_lr));
if (m_ver)
{
m_len = (int)Math.Abs(m_y2_lr - m_y1_lr);
}
else
{
m_len = (int)Math.Abs(m_x2_lr - m_x1_lr);
}
m_inc = (m_ver ? ((y2 > y1) ? 1 : -1) : ((x2 > x1) ? 1 : -1));
m_interpolator = new LineInterpolatorDDA2(m_ver ? x1 : y1,
m_ver ? x2 : y2,
(int)m_len);
}
//--------------------------------------------------------------------
public LineInterpolatorBresenham(int x1, int y1, int x2, int y2)
{
_x1_lr = (line_lr(x1));
_y1_lr = (line_lr(y1));
_x2_lr = (line_lr(x2));
_y2_lr = (line_lr(y2));
_ver = (Math.Abs(_x2_lr - _x1_lr) < Math.Abs(_y2_lr - _y1_lr));
if (_ver)
{
_len = (int)Math.Abs(_y2_lr - _y1_lr);
}
else
{
_len = (int)Math.Abs(_x2_lr - _x1_lr);
}
_inc = (_ver ? ((y2 > y1) ? 1 : -1) : ((x2 > x1) ? 1 : -1));
_interpolator = new LineInterpolatorDDA2(_ver ? x1 : y1,
_ver ? x2 : y2,
_len);
}
//----------------------------------------------------------------
public void ReSync(double xe, double ye, int len)
{
// Assume x1,y1 are equal to the ones at the previous end point
int x1 = m_coord_x.Y;
int y1 = m_coord_y.Y;
int sx1 = m_scale_x.Y;
int sy1 = m_scale_y.Y;
// Calculate transformed coordinates at x2,y2
double xt = xe;
double yt = ye;
m_trans_dir.Transform(ref xt, ref yt);
int x2 = AggMath.iround(xt * SUBPIXEL_SCALE);
int y2 = AggMath.iround(yt * SUBPIXEL_SCALE);
double delta = 1 / (double)SUBPIXEL_SCALE;
double dx;
double dy;
// Calculate scale by X at x2,y2
dx = xt + delta;
dy = yt;
m_trans_inv.Transform(ref dx, ref dy);
dx -= xe;
dy -= ye;
int sx2 = (int)AggMath.uround(SUBPIXEL_SCALE / Math.Sqrt(dx * dx + dy * dy)) >> SUBPIXEL_SHIFT;
// Calculate scale by Y at x2,y2
dx = xt;
dy = yt + delta;
m_trans_inv.Transform(ref dx, ref dy);
dx -= xe;
dy -= ye;
int sy2 = (int)AggMath.uround(SUBPIXEL_SCALE / Math.Sqrt(dx * dx + dy * dy)) >> SUBPIXEL_SHIFT;
// Initialize the interpolators
m_coord_x = new LineInterpolatorDDA2(x1, x2, (int)len);
m_coord_y = new LineInterpolatorDDA2(y1, y2, (int)len);
m_scale_x = new LineInterpolatorDDA2(sx1, sx2, (int)len);
m_scale_y = new LineInterpolatorDDA2(sy1, sy2, (int)len);
}