---
name: "wxMask"
section: "3erl"
platform: "linux"
package: "erlang-manpages"
version: "1:25.2.3+dfsg-1+deb12u4"
release: "Debian 12 (Bookworm)"
platforms: ["linux"]
url: "https://new.carta.tech/wxMask"
---

# wxMask(3erl)

Functions for wxMask class

## NAME

wxMask - Functions for wxMask class

## DESCRIPTION

This class encapsulates a monochrome mask bitmap, where the masked area is black and the unmasked area is white.

When associated with a bitmap and drawn in a device context, the unmasked area of the bitmap will be drawn, and the masked area will not be drawn.

Note: A mask can be associated also with a bitmap with an alpha channel but drawing such bitmaps under wxMSW may be slow so using them should be avoided if drawing performance is an important factor.

See: *wxBitmap*, *wxDC:blit/6*, *wxMemoryDC*

wxWidgets docs: wxMask

## DATA TYPES

```
wxMask() = wx:wx_object()
```

## EXPORTS

```
new() -> wxMask()
```

Default constructor.

```
new(Bitmap) -> wxMask()
```

Types:

Bitmap = wxBitmap:wxBitmap()\

Constructs a mask from a monochrome bitmap.

```
new(Bitmap, Index) -> wxMask()
```

```
new(Bitmap, Colour) -> wxMask()
```

Types:

Bitmap = wxBitmap:wxBitmap()\
 Colour = wx:wx\_colour()\

Constructs a mask from a bitmap and a colour that indicates the background.

```
destroy(This :: wxMask()) -> ok
```

Destroys the *wxMask* object and the underlying bitmap data.

```
create(This, Bitmap) -> boolean()
```

Types:

This = wxMask()\
 Bitmap = wxBitmap:wxBitmap()\

Constructs a mask from a monochrome bitmap.

```
create(This, Bitmap, Index) -> boolean()
```

```
create(This, Bitmap, Colour) -> boolean()
```

Types:

This = wxMask()\
 Bitmap = wxBitmap:wxBitmap()\
 Colour = wx:wx\_colour()\

Constructs a mask from a bitmap and a colour that indicates the background.