API reference - Class BitmapBuffer

Notation used in Ruby API documentation

Module: lay

Description: A simplistic pixel buffer representing monochrome image

This object is mainly provided for offline rendering of layouts in Qt-less environments. It supports a rectangular pixel space with color values encoded in single bits.

This class supports basic operations such as initialization, single-pixel access and I/O to PNG.

This class has been introduced in version 0.28.

Public constructors

new BitmapBuffer ptrnew(unsigned int width,
unsigned int height)
Creates a pixel buffer object

Public methods

[const]bool!=(const BitmapBuffer other)Returns a value indicating whether self is not identical to the other image
[const]bool==(const BitmapBuffer other)Returns a value indicating whether self is identical to the other image
void_createEnsures the C++ object is created
void_destroyExplicitly destroys the object
[const]bool_destroyed?Returns a value indicating whether the object was already destroyed
[const]bool_is_const_object?Returns a value indicating whether the reference is a const reference
void_manageMarks the object as managed by the script side.
void_unmanageMarks the object as no longer owned by the script side.
voidassign(const BitmapBuffer other)Assigns another object to self
[const]new BitmapBuffer ptrdupCreates a copy of self
voidfill(bool color)Fills the pixel buffer with the given pixel value
[const]unsigned intheightGets the height of the pixel buffer in pixels
[const]boolpixel(unsigned int x,
unsigned int y)
Gets the value of the pixel at position x, y
voidset_pixel(unsigned int x,
unsigned int y,
bool c)
Sets the value of the pixel at position x, y
voidswap(BitmapBuffer other)Swaps data with another BitmapBuffer object
[const]bytesto_png_dataConverts the pixel buffer to a PNG byte stream
[const]QImageto_qimageConverts the pixel buffer to a QImage object
[const]unsigned intwidthGets the width of the pixel buffer in pixels
[const]voidwrite_png(string file)Writes the pixel buffer to a PNG file

Public static methods and constants

BitmapBufferfrom_png_data(bytes data)Reads the pixel buffer from a PNG byte stream
BitmapBufferfrom_qimage(const QImage qimage)Creates a pixel buffer object from a QImage object
BitmapBufferread_png(string file)Reads the pixel buffer from a PNG file

Deprecated methods (protected, public, static, non-static and constructors)

voidcreateUse of this method is deprecated. Use _create instead
voiddestroyUse of this method is deprecated. Use _destroy instead
[const]booldestroyed?Use of this method is deprecated. Use _destroyed? instead
[const]boolis_const_object?Use of this method is deprecated. Use _is_const_object? instead

Detailed description

!=

Signature: [const] bool != (const BitmapBuffer other)

Description: Returns a value indicating whether self is not identical to the other image

==

Signature: [const] bool == (const BitmapBuffer other)

Description: Returns a value indicating whether self is identical to the other image

_create

Signature: void _create

Description: Ensures the C++ object is created

Use this method to ensure the C++ object is created, for example to ensure that resources are allocated. Usually C++ objects are created on demand and not necessarily when the script object is created.

_destroy

Signature: void _destroy

Description: Explicitly destroys the object

Explicitly destroys the object on C++ side if it was owned by the script interpreter. Subsequent access to this object will throw an exception. If the object is not owned by the script, this method will do nothing.

_destroyed?

Signature: [const] bool _destroyed?

Description: Returns a value indicating whether the object was already destroyed

This method returns true, if the object was destroyed, either explicitly or by the C++ side. The latter may happen, if the object is owned by a C++ object which got destroyed itself.

_is_const_object?

Signature: [const] bool _is_const_object?

Description: Returns a value indicating whether the reference is a const reference

This method returns true, if self is a const reference. In that case, only const methods may be called on self.

_manage

Signature: void _manage

Description: Marks the object as managed by the script side.

After calling this method on an object, the script side will be responsible for the management of the object. This method may be called if an object is returned from a C++ function and the object is known not to be owned by any C++ instance. If necessary, the script side may delete the object if the script's reference is no longer required.

Usually it's not required to call this method. It has been introduced in version 0.24.

_unmanage

Signature: void _unmanage

Description: Marks the object as no longer owned by the script side.

Calling this method will make this object no longer owned by the script's memory management. Instead, the object must be managed in some other way. Usually this method may be called if it is known that some C++ object holds and manages this object. Technically speaking, this method will turn the script's reference into a weak reference. After the script engine decides to delete the reference, the object itself will still exist. If the object is not managed otherwise, memory leaks will occur.

Usually it's not required to call this method. It has been introduced in version 0.24.

assign

Signature: void assign (const BitmapBuffer other)

Description: Assigns another object to self

create

Signature: void create

Description: Ensures the C++ object is created

Use of this method is deprecated. Use _create instead

Use this method to ensure the C++ object is created, for example to ensure that resources are allocated. Usually C++ objects are created on demand and not necessarily when the script object is created.

destroy

Signature: void destroy

Description: Explicitly destroys the object

Use of this method is deprecated. Use _destroy instead

Explicitly destroys the object on C++ side if it was owned by the script interpreter. Subsequent access to this object will throw an exception. If the object is not owned by the script, this method will do nothing.

destroyed?

Signature: [const] bool destroyed?

Description: Returns a value indicating whether the object was already destroyed

Use of this method is deprecated. Use _destroyed? instead

This method returns true, if the object was destroyed, either explicitly or by the C++ side. The latter may happen, if the object is owned by a C++ object which got destroyed itself.

dup

Signature: [const] new BitmapBuffer ptr dup

Description: Creates a copy of self

Python specific notes:
This method also implements '__copy__' and '__deepcopy__'.

fill

Signature: void fill (bool color)

Description: Fills the pixel buffer with the given pixel value

from_png_data

Signature: [static] BitmapBuffer from_png_data (bytes data)

Description: Reads the pixel buffer from a PNG byte stream

This method may not be available if PNG support is not compiled into KLayout.

from_qimage

Signature: [static] BitmapBuffer from_qimage (const QImage qimage)

Description: Creates a pixel buffer object from a QImage object

height

Signature: [const] unsigned int height

Description: Gets the height of the pixel buffer in pixels

is_const_object?

Signature: [const] bool is_const_object?

Description: Returns a value indicating whether the reference is a const reference

Use of this method is deprecated. Use _is_const_object? instead

This method returns true, if self is a const reference. In that case, only const methods may be called on self.

new

Signature: [static] new BitmapBuffer ptr new (unsigned int width, unsigned int height)

Description: Creates a pixel buffer object

width:The width in pixels
height:The height in pixels

The pixels are basically uninitialized. You will need to use fill to initialize them to a certain value.

Python specific notes:
This method is the default initializer of the object.

pixel

Signature: [const] bool pixel (unsigned int x, unsigned int y)

Description: Gets the value of the pixel at position x, y

read_png

Signature: [static] BitmapBuffer read_png (string file)

Description: Reads the pixel buffer from a PNG file

This method may not be available if PNG support is not compiled into KLayout.

set_pixel

Signature: void set_pixel (unsigned int x, unsigned int y, bool c)

Description: Sets the value of the pixel at position x, y

swap

Signature: void swap (BitmapBuffer other)

Description: Swaps data with another BitmapBuffer object

to_png_data

Signature: [const] bytes to_png_data

Description: Converts the pixel buffer to a PNG byte stream

This method may not be available if PNG support is not compiled into KLayout.

to_qimage

Signature: [const] QImage to_qimage

Description: Converts the pixel buffer to a QImage object

width

Signature: [const] unsigned int width

Description: Gets the width of the pixel buffer in pixels

write_png

Signature: [const] void write_png (string file)

Description: Writes the pixel buffer to a PNG file

This method may not be available if PNG support is not compiled into KLayout.