private Bitmap GetBitmapUseRaster(PointF[] points, byte[] types, Envelope dstEnvelope, Size size)
{
if (dstEnvelope == null || size.IsEmpty)
{
return(null);
}
using (IVector2BitmapConverter c = new Vector2BitmapConverter())
{
Bitmap buffer = new Bitmap(size.Width, size.Height, PixelFormat.Format24bppRgb);
c.ToBitmapUseRasterCoord(points, types, Color.Red, Color.Black, dstEnvelope, size, ref buffer);
return(buffer);
}
}
/// <summary>
/// 函数GetBitmapUseRasterII解决大图像栅格化出现内存溢出的错误
/// 解决方法：
/// 1、先按照AOI最小外包矩形栅格化；
/// 2、将栅格化后的索引平移至大图像。
/// </summary>
/// <param name="points"></param>
/// <param name="types"></param>
/// <param name="dstEnvelope"></param>
/// <param name="size"></param>
/// <param name="offsetX"></param>
/// <param name="offsetY"></param>
/// <param name="newSize"></param>
/// <returns></returns>
private Bitmap GetBitmapUseRasterII(PointF[] points, byte[] types, Envelope dstEnvelope, Size size,
out int offsetX, out int offsetY, out Size newSize)
{
offsetX = offsetY = 0;
newSize = Size.Empty;
if (dstEnvelope == null || size.IsEmpty)
{
return(null);
}
//
float minX = float.MaxValue;
float maxX = int.MinValue;
float minY = float.MaxValue;
float maxY = float.MinValue;
for (int i = 0; i < points.Length; i++)
{
if (points[i].X < minX)
{
minX = points[i].X;
}
if (points[i].X > maxX)
{
maxX = points[i].X;
}
if (points[i].Y < minY)
{
minY = points[i].Y;
}
if (points[i].Y > maxY)
{
maxY = points[i].Y;
}
}
//
offsetX = (int)minX;
offsetY = (int)minY;
int width = (int)(maxX - minX);
int height = (int)(maxY - minY);
if (width <= 0 || height <= 0)
{
return(null);
}
newSize = new Size(width, height);
for (int i = 0; i < points.Length; i++)
{
points[i].X -= minX;
points[i].Y -= minY;
}
//
double xSpan = dstEnvelope.Width / size.Width;
double ySpan = dstEnvelope.Height / size.Height;
double minXCoord = dstEnvelope.MinX + offsetX * xSpan;
double maxYCoord = dstEnvelope.MaxY - offsetY * ySpan;
double maxXCoord = minXCoord + width * xSpan;
double minYCoord = maxYCoord - height * ySpan;
Envelope newEnvelope = new Envelope(minXCoord, minYCoord, maxXCoord, maxYCoord);
//offsetY = Math.Abs(offsetY);
//
using (IVector2BitmapConverter c = new Vector2BitmapConverter())
{
Bitmap buffer = new Bitmap(width, height, PixelFormat.Format24bppRgb);
c.ToBitmapUseRasterCoord(points, types, Color.Red, Color.Black, newEnvelope, newSize, ref buffer);
return(buffer);
}
}
