Added BitmapBrush

[beklemeto]

This pull request adds a BitmapBrush. Tested and used successfully for months with v1.4.1. I tried to port the changes to the master branch. Sorry for the untidy pull-request, as it's my first here on github.

[drewnoakes]

Looks great though @jingwood should sign off.

Would be amazing if you could add an example of using this to one of the demo apps.

[drewnoakes]

Using <summary> will allow these docs to appear in IDE tooling etc.

Suggested change

	///
	/// Extend the edges of the source out by clamping sample points outside the source
	/// to the edges.
	///
	/// <summary>
	/// Extend the edges of the source out by clamping sample points outside the source
	/// to the edges.
	/// </summary>

Ditto below.

[drewnoakes]

Is this right? It seems to rely upon there being a d2dbitmapHandle value in scope, where the previous code (and the #define above) only rely on their "arguments".

[jingwood]

It seems that both arguments, contextHandle and bitmapHandle, should be used. However, RetrieveD2DBitmap is currently not being utilized anywhere. I plan to fix this in the future.

[drewnoakes]

I think this can be get-only.

Suggested change

	public D2DBitmap Bitmap { get; private set; }
	public D2DBitmap Bitmap { get; }

[jingwood]

Hi @beklemeto! Thanks very much for your work on this.

Could you please address the points that @drewnoakes raised? I'll merge this PR once those issues are resolved.

Additionally, if you could provide an example program, that would be great. It will help us better understand how your feature works.

[jingwood]

I'm going to merge this and make a simple example code to test it.

[beklemeto]

I'm going to merge this and make a simple example code to test it.

Thank you for dealing with it. I'm not able to react swiftly.

Maybe it would be useful to point my exact code excerpt on how I used it:

public void DrawPatternPolygon(D2DPoint[] points, Bitmap pattern)
{
	if (graphics != null)
	{
		using (var bmp = panel.Device.CreateBitmapGraphics(pattern.Width, pattern.Height))
		{
			using (var d2dbitmap = panel.Device.LoadBitmap(ImageToByte(pattern)))
			{
				bmp.BeginRender();
				bmp.DrawBitmap(d2dbitmap, new D2DRect(0, 0, pattern.Width, pattern.Height), 1f);
				bmp.EndRender();

				using (var patternBrush = panel.Device.CreateBitmapBrush(bmp.GetBitmap(), D2DExtendMode.Wrap, D2DExtendMode.Wrap, D2DBitmapInterpolationMode.Linear))
				{
					graphics.DrawPolygon(points, D2DColor.Black, 0, D2DDashStyle.Solid, patternBrush);
				}
			}
		}
	}
}

The code repeats a pattern horizontally and vertically (Wrap extend mode) as long as the polygon is fully filled. Please note the double Bitmap conversion through byte array and then drawing onto a bitmap graphics. This was the only way possible to convert transparent GDI Bitmap into a transparent D2DBitmap.

Excellen description on how to use the extend parameters of the brush can be found here:
https://github.com/MicrosoftDocs/win32/blob/docs/desktop-src/Direct2D/direct2d-brushes-overview.md