godot/doc/classes/BitMap.xml

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<?xml version="1.0" encoding="UTF-8" ?>
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<class name="BitMap" inherits="Resource" version="4.0">
<brief_description>
Boolean matrix.
</brief_description>
<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.
</description>
<tutorials>
</tutorials>
<methods>
<method name="create">
<return type="void" />
<argument index="0" name="size" type="Vector2" />
<description>
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Creates a bitmap with the specified size, filled with [code]false[/code].
</description>
</method>
<method name="create_from_image_alpha">
<return type="void" />
<argument index="0" name="image" type="Image" />
<argument index="1" name="threshold" type="float" default="0.1" />
<description>
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Creates a bitmap that matches the given image dimensions, every element of the bitmap is set to [code]false[/code] if the alpha value of the image at that position is equal to [code]threshold[/code] or less, and [code]true[/code] in other case.
</description>
</method>
<method name="get_bit" qualifiers="const">
<return type="bool" />
<argument index="0" name="position" type="Vector2" />
<description>
Returns bitmap's value at the specified position.
</description>
</method>
<method name="get_size" qualifiers="const">
<return type="Vector2" />
<description>
Returns bitmap's dimensions.
</description>
</method>
<method name="get_true_bit_count" qualifiers="const">
<return type="int" />
<description>
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Returns the amount of bitmap elements that are set to [code]true[/code].
</description>
</method>
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<method name="grow_mask">
<return type="void" />
<argument index="0" name="pixels" type="int" />
<argument index="1" name="rect" type="Rect2" />
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<description>
Applies morphological dilation or erosion to the bitmap. If [code]pixels[/code] is positive, dilation is applied to the bitmap. If [code]pixels[/code] is negative, erosion is applied to the bitmap. [code]rect[/code] defines the area where the morphological operation is applied. Pixels located outside the [code]rect[/code] are unaffected by [method grow_mask].
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</description>
</method>
<method name="opaque_to_polygons" qualifiers="const">
<return type="Array" />
<argument index="0" name="rect" type="Rect2" />
<argument index="1" name="epsilon" type="float" default="2.0" />
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<description>
Creates an [Array] of polygons covering a rectangular portion of the bitmap. It uses a marching squares algorithm, followed by Ramer-Douglas-Peucker (RDP) reduction of the number of vertices. Each polygon is described as a [PackedVector2Array] of its vertices.
To get polygons covering the whole bitmap, pass:
[codeblock]
Rect2(Vector2(), get_size())
[/codeblock]
[code]epsilon[/code] is passed to RDP to control how accurately the polygons cover the bitmap: a lower [code]epsilon[/code] corresponds to more points in the polygons.
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</description>
</method>
<method name="set_bit">
<return type="void" />
<argument index="0" name="position" type="Vector2" />
<argument index="1" name="bit" type="bool" />
<description>
Sets the bitmap's element at the specified position, to the specified value.
</description>
</method>
<method name="set_bit_rect">
<return type="void" />
<argument index="0" name="rect" type="Rect2" />
<argument index="1" name="bit" type="bool" />
<description>
Sets a rectangular portion of the bitmap to the specified value.
</description>
</method>
</methods>
</class>