D1166: Discard Map Option Requires Write Map Option
D2D1_MAP_OPTIONS_DISCARD must be combined with D2D1_MAP_OPTIONS_WRITE
Direct2D may output this message if an application calls ID2D1Bitmap1::Map with D2D1_MAP_OPTIONS_DISCARD but not D2D1_MAP_OPTIONS_WRITE.
The DISCARD option requires WRITE in order to be a useful operation for an application. See D2D1_MAP_OPTIONS for a description of map options. When calling ID2D1Bitmap1::Map, consider which type of access the application needs.