Type Registry Item Attribute

private const string CATEGORY_PATH = "Sirenix.TypeSelector.Demo";
private const string BASE_ITEM_NAME = "Painting Tools";
private const string PATH = CATEGORY_PATH + "/" + BASE_ITEM_NAME;

[TypeRegistryItem(Name = BASE_ITEM_NAME, Icon = SdfIconType.Tools, CategoryPath = CATEGORY_PATH, Priority = Int32.MinValue)]
public abstract class Base { }

[TypeRegistryItem(darkIconColorR: 0.8f, darkIconColorG: 0.3f,
                        lightIconColorR: 0.3f, lightIconColorG: 0.1f,
                        Name = "Brush", CategoryPath = PATH, Icon = SdfIconType.BrushFill, Priority = Int32.MinValue)]
public class InheritorA : Base
{
    public Color Color = Color.red;
    public float PaintRemaining = 0.4f;
}

[TypeRegistryItem(darkIconColorG: 0.8f, darkIconColorB: 0.3f,
                        lightIconColorG: 0.3f, lightIconColorB: 0.1f,
                        Name = "Paint Bucket", CategoryPath = PATH, Icon = SdfIconType.PaintBucket, Priority = Int32.MinValue)]
public class InheritorB : Base
{
    public Color Color = Color.green;
    public float PaintRemaining = 0.8f;
}

[TypeRegistryItem(darkIconColorB: 0.8f, darkIconColorG: 0.3f,
                        lightIconColorB: 0.3f, lightIconColorG: 0.1f,
                        Name = "Palette", CategoryPath = PATH, Icon = SdfIconType.PaletteFill, Priority = Int32.MinValue)]
public class InheritorC : Base
{
    public ColorPaletteItem[] Colors =
    {
        new ColorPaletteItem(Color.blue, 0.8f),
        new ColorPaletteItem(Color.red, 0.5f),
        new ColorPaletteItem(Color.green, 1.0f),
        new ColorPaletteItem(Color.white, 0.6f),
    };
}

[ShowInInspector]
[PolymorphicDrawerSettings(ShowBaseType = false)]
[InlineProperty]
public Base PaintingItem;

public struct ColorPaletteItem
{
    public Color Color;
    public float Remaining;

    public ColorPaletteItem(Color color, float remaining)
    {
        this.Color = color;
        this.Remaining = remaining;
    }
}