A memory device context provides a means to draw graphics onto a bitmap. When drawing in to a mono-bitmap, using
A bitmap must be selected into the new memory DC before it may be used for anything. Typical usage is as follows:
Note that the memory DC must be deleted (or the bitmap selected out of it) before a bitmap can be reselected into another memory DC.
And, before performing any other operations on the bitmap data, the bitmap must be selected out of the memory DC:
This happens automatically when
See:
This class is derived (and can use functions) from:
wxWidgets docs:
Constructs a new memory device context.
Use the
Constructs a new memory device context having the same characteristics as the given existing device context.
This constructor creates a memory device context
Works exactly like
drawing on this DC.
Using
Before using the updated bitmap data, make sure to select it out of context first either by selecting ?wxNullBitmap into the device context or destroying the device context entirely.
If the bitmap is already selected in this device context, nothing is done. If it is selected in another context, the function asserts and drawing on the bitmap won't work correctly.
See:
Selects the given bitmap into the device context, to use as the memory bitmap.
Selecting the bitmap into a memory DC allows you to draw into the DC (and therefore the bitmap) and also to use
If the argument is ?wxNullBitmap (or some other uninitialised
Destroys the object.