/// <summary>
/// Create a bitmap structure with bits from this raw icon image.
/// </summary>
/// <returns>An array of bytes that represent data to create a bitmap.</returns>
/// <remarks></remarks>
private byte[] _makeBitmap()
{
byte[] _makeBitmapRet = default;
if (!IsPngFormat)
{
_makeBitmapRet = _image;
return(_makeBitmapRet);
}
IntPtr bmp = default;
var hbmp = Resources.MakeDIBSection((Bitmap)ToImage(), ref bmp);
var mm = new SafePtr();
var bm = new BITMAPINFOHEADER();
int maskSize;
int w = _entry.cWidth;
int h = _entry.cHeight;
if (w == 0)
{
w = 256;
}
if (h == 0)
{
h = 256;
}
bm.biSize = 40;
bm.biWidth = w;
bm.biHeight = h * 2;
bm.biPlanes = 1;
bm.biBitCount = 32;
bm.biSizeImage = w * h * 4;
maskSize = (int)(Math.Max(w, 32) * h / 8d);
mm.Alloc(bm.biSizeImage + 40 + maskSize);
var ptr1 = mm.DangerousGetHandle() + 40;
var ptr2 = mm.DangerousGetHandle() + 40 + bm.biSizeImage;
Marshal.StructureToPtr(bm, mm.DangerousGetHandle(), false);
Native.MemCpy(bmp, ptr1, bm.biSizeImage);
bm = mm.ToStruct <BITMAPINFOHEADER>();
_setMask(ptr1, ptr2, w, h);
_entry.dwImageSize = (int)mm.Length;
_makeBitmapRet = (byte[])mm;
mm.Free();
NativeShell.DeleteObject(hbmp);
return(_makeBitmapRet);
}