Documentation: SharpDX.Color4

[tradesmart]

It's important to note that the alpha value of SharpDX.Color4 should be a float between 0 and 1.0, just like opacity values. In the example, 50 would make the color completely opaque, as would any value >=1. Therefore, the data type of alpha cannot be byte or int if you want it to behave as expected. This, of course, is different than the range of alpha values between 0 and 255 we use for Windows.Media.Brush WPF colors.

http://ninjatrader.com/support/helpG..._rendering.htm

// create a 3 component color using rgb values
 SharpDX.Color3 dxColor3 = new SharpDX.Color3(255, 0, 0);
// create a 4 component color using rgb + alpha (transparency)
SharpDX.Color4 dxColor4 = new SharpDX.Color4(dxColor3, [COLOR=Red][B]50[/B][/COLOR]); [COLOR=SeaGreen]// should be 0.5[/COLOR]
// solid color brush uses a Color4 during construction
SharpDX.Direct2D1.SolidColorBrush argbColorBrush = new SharpDX.Direct2D1.SolidColorBrush(RenderTarget, dxColor4);

[NinjaTrader_JessicaP]

Thank you for your report, tradesmart. This information has been passed on to the responsible teams, who will update the help guide accordingly.

[tradesmart]

And not only alpha values, but R, G, and B values also need to be floats. When converting from WPF brushes to SharpDX, you will need to divide each byte value by 255 to get the proper float values for SharpDX as shown in the attached image.

[NinjaTrader_JessicaP]

Thank you again, tradesmart. For reference and ease of understanding I am providing an excerpt from SharpDX' source for Color4 :

// https://github.com/sharpdx/SharpDX/blob/master/Source/SharpDX.Mathematics/Color4.cs
public static readonly Color4 Black = new Color4(0.0f, 0.0f, 0.0f, 1.0f);
public static readonly Color4 White = new Color4(1.0f, 1.0f, 1.0f, 1.0f);