Class BitMap

Boolean matrix.

Inheritance

Resource

RefCounted

Object

BitMap

Remarks

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

convert_to_image

Qualifiers: const

Returns an image of the same size as the bitmap and with a Format of type Image.FORMAT_L8. true bits of the bitmap are being converted into white pixels, and false bits into black.

Image convert_to_image

create(Vector2i)

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

void create(Vector2i size)

Parameters

size Vector2i

create_from_image_alpha(Image, float)

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.

void create_from_image_alpha(Image image, float threshold)

Parameters

image Image

threshold float

get_bit(int, int)

Qualifiers: const

Returns bitmap's value at the specified position.

bool get_bit(int x, int y)

Parameters

x int

y int

get_bitv(Vector2i)

Qualifiers: const

Returns bitmap's value at the specified position.

bool get_bitv(Vector2i position)

Parameters

position Vector2i

get_size

Qualifiers: const

Returns bitmap's dimensions.

Vector2i get_size

get_true_bit_count

Qualifiers: const

Returns the number of bitmap elements that are set to true.

int get_true_bit_count

grow_mask(int, Rect2i)

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 BitMap.grow_mask.

void grow_mask(int pixels, Rect2i rect)

Parameters

pixels int

rect Rect2i

opaque_to_polygons(Rect2i, float)

Qualifiers: const

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:

Rect2(Vector2(), get_size())

epsilon is passed to RDP to control how accurately the polygons cover the bitmap: a lower epsilon corresponds to more points in the polygons.

PackedVector2Array[] opaque_to_polygons(Rect2i rect, float epsilon)

Parameters

rect Rect2i

epsilon float

resize(Vector2i)

Resizes the image to new_size.

void resize(Vector2i new_size)

Parameters

new_size Vector2i

set_bit(int, int, bool)

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

void set_bit(int x, int y, bool bit)

Parameters

x int

y int

bit bool

set_bit_rect(Rect2i, bool)

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

void set_bit_rect(Rect2i rect, bool bit)

Parameters

rect Rect2i

bit bool

set_bitv(Vector2i, bool)

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

void set_bitv(Vector2i position, bool bit)

Parameters

position Vector2i

bit bool