public static List <List <Vector2i> > DrawPolygonTranslate(Vector2i[] vs, int vp)
{
Vector2i max = vs[0];
Vector2i min = vs[0];
for (int i = 1; i < vp; i++)
{
max = Vector2i.Max(max, vs[i]);
min = Vector2i.Min(min, vs[i]);
}
Vector2i[] newV = vs.Select(t =>
{
return(t - min);
}).ToArray();
Vector2i resolute = max - min;
ConvexPolygonScanning scan = new ConvexPolygonScanning();
scan.SetResolution(resolute[0] + 1, resolute[1] + 1);
scan.DrawPolygon(newV, newV.Length);
// scan.Show();
List <List <Vector2i> > results = new List <List <Vector2i> >();
for (int i = scan.mMapYresb - 1; i >= 0; i--)
{
int idx = i * scan.mMapXresb;
List <Vector2i> result = new List <Vector2i>();
for (int j = 0; j < scan.mMapXresb; ++j)
{
if (scan.mResultMap[idx + j] == 1)
{
result.Add(new Vector2i(j, i));
}
}
if (result.Count > 0)
{
result = result.Select(t =>
{
return(t + min);
}).ToList();
results.Add(result);
}
}
return(results);
}
public static List <Vector2i> Scan(List <Vector2i> poly)
{
List <Vector2i> results = new List <Vector2i>();
Vector2i max = new Vector2i(int.MinValue, int.MinValue);
Vector2i min = new Vector2i(int.MaxValue, int.MaxValue);
foreach (Vector2i v in poly)
{
max = Vector2i.Max(v, max);
min = Vector2i.Min(v, min);
}
List <Vector2i> trans = poly.Select(t => { return(t - min); }).ToList();
int height = max[1] - min[1];
List <ScanEdge> scanLines = new List <ScanEdge>();
int count = trans.Count;
int count1 = count - 1;
for (int i = 0; i < count; ++i)
{
Vector2i ps = trans[i];
int post = (i + 1) % count;
Vector2i pe = trans[post];
if (ps[1] == pe[1]) // 水平 去掉
{
Vector2i hori = Vector2i.GetVector2i(ps[0], pe[0]);
for (int hi = hori[0]; hi <= hori[1]; ++hi)
{
results.Add(new Vector2i(hi, ps[1]));
}
continue;
}
int pre = (i + count1) % count;
Vector2i pss = trans[pre];
int ppost = (post + 1) % count;
Vector2i pee = trans[ppost];
double dx = (ps[0] - pe[0]) * 1.0f / (ps[1] - pe[1]);
bool yiG0 = ps[1] < pe[1];
double startX = yiG0 ? ps[0] : pe[0];
int ymin = yiG0 ? ps[1] : pe[1];
int ymax = yiG0 ? pe[1] : ps[1];
if (pe[1] > ps[1])
{
if (pee[1] >= pe[1])
{
ymax -= 1;
}
}
else
{
if (pss[1] >= ps[1])
{
ymax -= 1;
}
}
ScanEdge ep = new ScanEdge();
ep.mMinY = ymin;
ep.mMaxY = ymax;
ep.mStartX = startX;
ep.mDx = dx;
scanLines.Add(ep);
}
for (int i = 0; i < height; ++i)
{
List <ScanEdge> tmp = scanLines.FindAll(delegate(ScanEdge line) { return(line.Include(i)); });
tmp.Sort((e1, e2) =>
{
//此处可以不考虑 斜率。 x相等时，不用考虑谁在前谁在后
return(e1.mStartX.CompareTo(e2.mStartX));
});
if (tmp.Count % 2 != 0)
{
throw new Exception("必须是偶数");
}
for (int idx = 0; idx < tmp.Count; idx += 2)
{
int next = idx + 1;
int x1 = (int)tmp[idx].mStartX;
int x2 = (int)tmp[next].mStartX;
if (x1 > x2)
{
continue;
}
for (int xi = x1; xi <= x2; ++xi)
{
results.Add(new Vector2i(xi, i));
}
tmp[idx].Increase();
tmp[next].Increase();
}
scanLines.RemoveAll((t) => t.mMaxY == i);
}
results = results.Select(t => { return(t + min); }).ToList();
return(results);
}
