//--------------------------------------------------------------------
internal bool SweepScanline(GLScanline scline)
{
for (; ; )
{
if (m_scan_y > m_cellAARas.MaxY)
{
return false;
}
scline.ResetSpans();
CellAA[] cells;
int offset;
int num_cells;
m_cellAARas.GetCells(m_scan_y, out cells, out offset, out num_cells);
int cover = 0;
while (num_cells != 0)
{
unsafe
{
fixed (CellAA* cur_cell_h = &cells[0])
{
CellAA* cur_cell_ptr = cur_cell_h + offset;
int alpha;
int x = cur_cell_ptr->x;
int area = cur_cell_ptr->area;
cover += cur_cell_ptr->cover;
//accumulate all cells with the same X
while (--num_cells != 0)
{
offset++; //move next
cur_cell_ptr++; //move next
if (cur_cell_ptr->x != x)
{
break;
}
area += cur_cell_ptr->area;
cover += cur_cell_ptr->cover;
}
if (area != 0)
{
alpha = CalculateAlpha((cover << (poly_subpix.SHIFT + 1)) - area);
if (alpha != 0)
{
scline.AddCell(x, alpha);
}
x++;
}
if ((num_cells != 0) && (cur_cell_ptr->x > x))
{
alpha = CalculateAlpha(cover << (poly_subpix.SHIFT + 1));
if (alpha != 0)
{
scline.AddSpan(x, (cur_cell_ptr->x - x), alpha);
}
}
}
}
}
if (scline.SpanCount != 0) { break; }
++m_scan_y;
}
scline.CloseLine(m_scan_y);
++m_scan_y;
return true;
}
//--------------------------------------------------------------------
internal bool SweepScanline(Scanline scline)
{
for (; ;)
{
if (m_scan_y > m_cellAARas.MaxY)
{
return(false);
}
scline.ResetSpans();
//-------------------------
CellAA[] cells;
int offset;
int num_cells;
m_cellAARas.GetCells(m_scan_y, out cells, out offset, out num_cells);
int cover = 0;
while (num_cells != 0)
{
unsafe
{
fixed(CellAA *cur_cell_h = &cells[0])
{
CellAA *cur_cell_ptr = cur_cell_h + offset;
int x = cur_cell_ptr->x;
int area = cur_cell_ptr->area;
cover += cur_cell_ptr->cover;
//accumulate all cells with the same X
while (--num_cells != 0)
{
offset++; //move next
cur_cell_ptr++; //move next
if (cur_cell_ptr->x != x)
{
break;
}
area += cur_cell_ptr->area;
cover += cur_cell_ptr->cover;
}
if (area != 0)
{
//-----------------------------------------------
//single cell, for antialias look
//-----------------------------------------------
//calculate alpha from coverage value
int alpha = CalculateAlpha((cover << (poly_subpix.SHIFT + 1)) - area);
if (alpha != 0)
{
scline.AddCell(x, alpha);
}
x++;
}
if ((num_cells != 0) && (cur_cell_ptr->x > x))
{
//-----------------------------------------------
//this is long span , continuous color, solid look
//-----------------------------------------------
//calculate alpha from coverage value
int alpha = CalculateAlpha(cover << (poly_subpix.SHIFT + 1));
if (alpha != 0)
{
scline.AddSpan(x, (cur_cell_ptr->x - x), alpha);
}
}
}
}
}
if (scline.SpanCount != 0)
{
break;
}
++m_scan_y;
}
scline.CloseLine(m_scan_y);
++m_scan_y;
return(true);
}
