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.. Generated automatically by doc/tools/make_rst.py in Godot's source tree.
.. DO NOT EDIT THIS FILE, but the BitMap.xml source instead.
.. The source is found in doc/classes or modules/<name>/doc_classes.

.. _class_BitMap:

BitMap
======

**Inherits:** :ref:`Resource<class_Resource>` **<** :ref:`Reference<class_Reference>` **<** :ref:`Object<class_Object>`

Boolean matrix.

Description
-----------

A two-dimensional array of boolean values, can be used to efficiently store a binary matrix (every matrix element takes only one bit) and query the values using natural cartesian coordinates.

Methods
-------

+-------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| void                          | :ref:`create<class_BitMap_method_create>` **(** :ref:`Vector2<class_Vector2>` size **)**                                                                         |
+-------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| void                          | :ref:`create_from_image_alpha<class_BitMap_method_create_from_image_alpha>` **(** :ref:`Image<class_Image>` image, :ref:`float<class_float>` threshold=0.1 **)** |
+-------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| :ref:`bool<class_bool>`       | :ref:`get_bit<class_BitMap_method_get_bit>` **(** :ref:`Vector2<class_Vector2>` position **)** |const|                                                           |
+-------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| :ref:`Vector2<class_Vector2>` | :ref:`get_size<class_BitMap_method_get_size>` **(** **)** |const|                                                                                                |
+-------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| :ref:`int<class_int>`         | :ref:`get_true_bit_count<class_BitMap_method_get_true_bit_count>` **(** **)** |const|                                                                            |
+-------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| void                          | :ref:`grow_mask<class_BitMap_method_grow_mask>` **(** :ref:`int<class_int>` pixels, :ref:`Rect2<class_Rect2>` rect **)**                                         |
+-------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| :ref:`Array<class_Array>`     | :ref:`opaque_to_polygons<class_BitMap_method_opaque_to_polygons>` **(** :ref:`Rect2<class_Rect2>` rect, :ref:`float<class_float>` epsilon=2.0 **)** |const|      |
+-------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| void                          | :ref:`set_bit<class_BitMap_method_set_bit>` **(** :ref:`Vector2<class_Vector2>` position, :ref:`bool<class_bool>` bit **)**                                      |
+-------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| void                          | :ref:`set_bit_rect<class_BitMap_method_set_bit_rect>` **(** :ref:`Rect2<class_Rect2>` rect, :ref:`bool<class_bool>` bit **)**                                    |
+-------------------------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------+

Method Descriptions
-------------------

.. _class_BitMap_method_create:

- void **create** **(** :ref:`Vector2<class_Vector2>` size **)**

Creates a bitmap with the specified size, filled with ``false``.

----

.. _class_BitMap_method_create_from_image_alpha:

- void **create_from_image_alpha** **(** :ref:`Image<class_Image>` image, :ref:`float<class_float>` threshold=0.1 **)**

Creates a bitmap that matches the given image dimensions, every element of the bitmap is set to ``false`` if the alpha value of the image at that position is equal to ``threshold`` or less, and ``true`` in other case.

----

.. _class_BitMap_method_get_bit:

- :ref:`bool<class_bool>` **get_bit** **(** :ref:`Vector2<class_Vector2>` position **)** |const|

Returns bitmap's value at the specified position.

----

.. _class_BitMap_method_get_size:

- :ref:`Vector2<class_Vector2>` **get_size** **(** **)** |const|

Returns bitmap's dimensions.

----

.. _class_BitMap_method_get_true_bit_count:

- :ref:`int<class_int>` **get_true_bit_count** **(** **)** |const|

Returns the amount of bitmap elements that are set to ``true``.

----

.. _class_BitMap_method_grow_mask:

- void **grow_mask** **(** :ref:`int<class_int>` pixels, :ref:`Rect2<class_Rect2>` rect **)**

Applies morphological dilation or erosion to the bitmap. If ``pixels`` is positive, dilation is applied to the bitmap. If ``pixels`` is negative, erosion is applied to the bitmap. ``rect`` defines the area where the morphological operation is applied. Pixels located outside the ``rect`` are unaffected by :ref:`grow_mask<class_BitMap_method_grow_mask>`.

----

.. _class_BitMap_method_opaque_to_polygons:

- :ref:`Array<class_Array>` **opaque_to_polygons** **(** :ref:`Rect2<class_Rect2>` rect, :ref:`float<class_float>` epsilon=2.0 **)** |const|

----

.. _class_BitMap_method_set_bit:

- void **set_bit** **(** :ref:`Vector2<class_Vector2>` position, :ref:`bool<class_bool>` bit **)**

Sets the bitmap's element at the specified position, to the specified value.

----

.. _class_BitMap_method_set_bit_rect:

- void **set_bit_rect** **(** :ref:`Rect2<class_Rect2>` rect, :ref:`bool<class_bool>` bit **)**

Sets a rectangular portion of the bitmap to the specified value.

.. |virtual| replace:: :abbr:`virtual (This method should typically be overridden by the user to have any effect.)`
.. |const| replace:: :abbr:`const (This method has no side effects. It doesn't modify any of the instance's member variables.)`
.. |vararg| replace:: :abbr:`vararg (This method accepts any number of arguments after the ones described here.)`