private com.epl.geometry.SimpleRasterizer.Edge SortAET_(com.epl.geometry.SimpleRasterizer.Edge aet)
{
int num = 0;
for (com.epl.geometry.SimpleRasterizer.Edge e = aet; e != null; e = e.next)
{
num++;
}
sortedNum_ = num;
if (num == 1)
{
return(aet);
}
if (sortBuffer_ == null)
{
sortBuffer_ = new com.epl.geometry.SimpleRasterizer.Edge[System.Math.Max(num, 16)];
}
else
{
if (sortBuffer_.Length < num)
{
sortBuffer_ = new com.epl.geometry.SimpleRasterizer.Edge[System.Math.Max(num, sortBuffer_.Length * 2)];
}
}
{
int i = 0;
for (com.epl.geometry.SimpleRasterizer.Edge e_1 = aet; e_1 != null; e_1 = e_1.next)
{
sortBuffer_[i++] = e_1;
}
}
if (num == 2)
{
if (sortBuffer_[0].x > sortBuffer_[1].x)
{
com.epl.geometry.SimpleRasterizer.Edge tmp = sortBuffer_[0];
sortBuffer_[0] = sortBuffer_[1];
sortBuffer_[1] = tmp;
}
}
else
{
System.Array.Sort(sortBuffer_, 0, num, edgeCompare_);
}
aet = sortBuffer_[0];
sortBuffer_[0] = null;
com.epl.geometry.SimpleRasterizer.Edge prev = aet;
for (int i_1 = 1; i_1 < num; i_1++)
{
prev.next = sortBuffer_[i_1];
prev = sortBuffer_[i_1];
sortBuffer_[i_1] = null;
}
prev.next = null;
return(aet);
}
private void AddNewEdgesToAET_(int y)
{
if (y >= height_)
{
return;
}
com.epl.geometry.SimpleRasterizer.Edge edgesOnLine = ySortedEdges_[y];
if (edgesOnLine != null)
{
ySortedEdges_[y] = null;
edgesOnLine = SortAET_(edgesOnLine);
//sort new edges
numEdges_ -= sortedNum_;
//set in the sortAET
// merge the edges with sorted AET - O(n) operation
com.epl.geometry.SimpleRasterizer.Edge aet = activeEdgesTable_;
bool first = true;
com.epl.geometry.SimpleRasterizer.Edge newEdge = edgesOnLine;
com.epl.geometry.SimpleRasterizer.Edge prev_aet = null;
while (aet != null && newEdge != null)
{
if (aet.x > newEdge.x)
{
if (first)
{
activeEdgesTable_ = newEdge;
}
com.epl.geometry.SimpleRasterizer.Edge p = newEdge.next;
newEdge.next = aet;
if (prev_aet != null)
{
prev_aet.next = newEdge;
}
prev_aet = newEdge;
newEdge = p;
}
else
{
// aet.x <= newEdges.x
com.epl.geometry.SimpleRasterizer.Edge p = aet.next;
aet.next = newEdge;
if (prev_aet != null)
{
prev_aet.next = aet;
}
prev_aet = aet;
aet = p;
}
first = false;
}
if (activeEdgesTable_ == null)
{
activeEdgesTable_ = edgesOnLine;
}
}
}
private void EmitScans_()
{
if (activeEdgesTable_ == null)
{
return;
}
int w = 0;
com.epl.geometry.SimpleRasterizer.Edge e0 = activeEdgesTable_;
int x0 = (int)(e0.x >> 32);
for (com.epl.geometry.SimpleRasterizer.Edge e = e0.next; e != null; e = e.next)
{
if (evenOdd_)
{
w ^= 1;
}
else
{
w += e.dir;
}
if (e.x > e0.x)
{
int x = (int)(e.x >> 32);
if (w != 0)
{
int xx0 = Snap_(x0, 0, width_);
int xx = Snap_(x, 0, width_);
if (xx > xx0 && xx0 < width_)
{
scanBuffer_[scanPtr_++] = xx0;
scanBuffer_[scanPtr_++] = xx;
scanBuffer_[scanPtr_++] = e.y;
if (scanPtr_ == scanBuffer_.Length)
{
callback_.DrawScan(scanBuffer_, scanPtr_);
scanPtr_ = 0;
}
}
}
e0 = e;
x0 = x;
}
}
}
/// <summary>Call before starting the edges.</summary>
/// <remarks>
/// Call before starting the edges.
/// For example to render two polygons that consist of a single ring:
/// startAddingEdges();
/// addRing(...);
/// renderEdges(Rasterizer.EVEN_ODD);
/// addRing(...);
/// renderEdges(Rasterizer.EVEN_ODD);
/// For example to render a polygon consisting of three rings:
/// startAddingEdges();
/// addRing(...);
/// addRing(...);
/// addRing(...);
/// renderEdges(Rasterizer.EVEN_ODD);
/// </remarks>
public void StartAddingEdges()
{
if (numEdges_ > 0)
{
for (int i = 0; i < height_; i++)
{
for (com.epl.geometry.SimpleRasterizer.Edge e = ySortedEdges_[i]; e != null;)
{
com.epl.geometry.SimpleRasterizer.Edge p = e;
e = e.next;
p.next = null;
}
ySortedEdges_[i] = null;
}
activeEdgesTable_ = null;
}
minY_ = height_;
maxY_ = -1;
numEdges_ = 0;
}
private void AdvanceAET_()
{
if (activeEdgesTable_ == null)
{
return;
}
bool needSort = false;
com.epl.geometry.SimpleRasterizer.Edge prev = null;
for (com.epl.geometry.SimpleRasterizer.Edge e = activeEdgesTable_; e != null;)
{
e.y++;
if (e.y == e.ymax)
{
com.epl.geometry.SimpleRasterizer.Edge p = e;
e = e.next;
if (prev != null)
{
prev.next = e;
}
else
{
activeEdgesTable_ = e;
}
p.next = null;
continue;
}
e.x += e.dxdy;
if (prev != null && prev.x > e.x)
{
needSort = true;
}
prev = e;
e = e.next;
}
if (needSort)
{
//resort to fix the order
activeEdgesTable_ = SortAET_(activeEdgesTable_);
}
}
//reset for new edges
/// <summary>Add a single edge.</summary>
/// <param name="x1"/>
/// <param name="y1"/>
/// <param name="x2"/>
/// <param name="y2"/>
public void AddEdge(double x1, double y1, double x2, double y2)
{
if (y1 == y2)
{
return;
}
int dir = 1;
if (y1 > y2)
{
double temp;
temp = x1;
x1 = x2;
x2 = temp;
temp = y1;
y1 = y2;
y2 = temp;
dir = -1;
}
if (y2 < 0 || y1 >= height_)
{
return;
}
if (x1 < 0 && x2 < 0)
{
x1 = -1;
x2 = -1;
}
else
{
if (x1 >= width_ && x2 >= width_)
{
x1 = width_;
x2 = width_;
}
}
//clip to extent
double dxdy = (x2 - x1) / (y2 - y1);
if (y2 > height_)
{
y2 = height_;
x2 = dxdy * (y2 - y1) + x1;
}
if (y1 < 0)
{
x1 = dxdy * (0 - y1) + x1;
y1 = 0;
}
//do not clip x unless it is too small or too big
int bigX = System.Math.Max(width_ + 1, unchecked ((int)(0x7fffff)));
if (x1 < -unchecked ((int)(0x7fffff)))
{
//from earlier logic, x2 >= -1, therefore dxdy is not 0
y1 = (0 - x1) / dxdy + y1;
x1 = 0;
}
else
{
if (x1 > bigX)
{
//from earlier logic, x2 <= width_, therefore dxdy is not 0
y1 = (width_ - x1) / dxdy + y1;
x1 = width_;
}
}
if (x2 < -unchecked ((int)(0x7fffff)))
{
//from earlier logic, x1 >= -1, therefore dxdy is not 0
y2 = (0 - x1) / dxdy + y1;
x2 = 0;
}
else
{
if (x2 > bigX)
{
//from earlier logic, x1 <= width_, therefore dxdy is not 0
y2 = (width_ - x1) / dxdy + y1;
x2 = width_;
}
}
int ystart = (int)y1;
int yend = (int)y2;
if (ystart == yend)
{
return;
}
com.epl.geometry.SimpleRasterizer.Edge e = new com.epl.geometry.SimpleRasterizer.Edge();
e.x = (long)(x1 * 4294967296.0);
e.y = ystart;
e.ymax = yend;
e.dxdy = (long)(dxdy * 4294967296.0);
e.dir = dir;
if (ySortedEdges_ == null)
{
ySortedEdges_ = new com.epl.geometry.SimpleRasterizer.Edge[height_];
}
e.next = ySortedEdges_[e.y];
ySortedEdges_[e.y] = e;
if (e.y < minY_)
{
minY_ = e.y;
}
if (e.ymax > maxY_)
{
maxY_ = e.ymax;
}
numEdges_++;
}
