/// <summary>
/// This does not have to be used to work, but provides a default implementation for writing bitmap,
/// and will be used by the MapRasterLayer class during file creation.
/// </summary>
/// <param name="progressHandler"></param>
protected void DefaultWriteBitmap(IProgressHandler progressHandler)
{
if (DataSet.NumRowsInFile * DataSet.NumColumnsInFile > 8000 * 8000)
{
// For huge images, assume that GDAL or something was needed anyway,
// and we would rather avoid having to re-create the pyramids if there is any chance
// that the old values will work ok.
string pyrFile = Path.ChangeExtension(DataSet.Filename, ".mwi");
BitmapGetter = CreatePyramidImage(pyrFile, progressHandler);
OnItemChanged(this);
return;
}
Bitmap bmp = new Bitmap(DataSet.NumColumns, DataSet.NumRows, PixelFormat.Format32bppArgb);
if (_symbolizer.DrapeVectorLayers == false)
{
// Generate the colorscheme, modified by hillshading if that hillshading is used all in one pass
DataSet.DrawToBitmap(Symbolizer, bmp, progressHandler);
}
else
{
// work backwards. when we get to this layer do the colorscheme.
// First, use this raster and its colorscheme to drop the background
DataSet.PaintColorSchemeToBitmap(Symbolizer, bmp, progressHandler);
// Set up a graphics object with a transformation pre-set so drawing a geographic coordinate
// will draw to the correct location on the bitmap
Graphics g = Graphics.FromImage(bmp);
g.SmoothingMode = SmoothingMode.AntiAlias;
Extent extents = DataSet.Extent;
Rectangle target = new Rectangle(0, 0, bmp.Width, bmp.Height);
ImageProjection ip = new ImageProjection(extents, target);
// Cycle through each layer, and as long as it is not this layer, draw the bmp
foreach (ILegendItem layer in GetParentItem().LegendItems)
{
// Temporarily I am only interested in doing this for vector datasets
IFeatureLayer fl = layer as IFeatureLayer;
if (fl == null)
{
continue;
}
fl.DrawSnapShot(g, ip);
}
if (Symbolizer.ShadedRelief.IsUsed)
{
// After we have drawn the underlying texture, apply a hillshade if it is requested
Symbolizer.PaintShadingToBitmap(bmp, progressHandler);
}
}
InRamImage image = new InRamImage(bmp);
image.Bounds = DataSet.Bounds.Copy();
BitmapGetter = image;
Symbolizer.Validate();
OnInvalidate(this, new EventArgs());
OnItemChanged();
}