Frame, Image and Placement

These three objects are useful for animations or for image alignment within the Canvas. The most important thing to remember is:

That is, a Placement contains a Image which contains a Frame. Once that’s all done, the Placement can be placed on the Canvas.

Frame

class chafa.Frame(src_pixel_type: PixelType, src_pixels, src_width: int, src_height: int, src_rowstride: int)

This defines a frame of an image. This has to be added to an Image. The inputs are the same as in Canvas.draw_all_pixels().

Note

Best performance is achieved by passing a ctypes.Array for src_pixels. A fast way to do this is to use Pillow; specifically the Image.tobytes method.

Parameters:

  • src_pixel_type (PixelType) – The pixel type of src_pixels. This will determine what order the color channels will be read in and whether there is an alpha channel.

  • src_pixels (list|tuple|array.array|ctypes.Array) – The source pixel data. This is a one dimensional array where every block of 3 (or 4 depending on the PixelType) values represents one pixel of the image. The order of the channels is determined by src_pixel_type.

  • src_width (int) – The width of the source image.

  • src_height (int) – The width of the source image.

  • src_rowstride (int) – The number of values in src_image that represents one line pixels in the source image. Typically this will be the number of channels in the source image multiplied by src_width, e.g. for an image with no alpha channel and a width of 300 pixels, this will be 3*300.

Raises:

ValueError – if src_width, src_height or src_rowstride are less than or equal to 0.

Added in version 1.2.0.

Image

class chafa.Image

A container for a Frame. To be placed on a Placement.

Added in version 1.2.0.

property frame
Type:

Frame

The Frame for the image

Placement

After assigning a Placement to a Canvas with Canvas.placement, you can print the Canvas using Canvas.print().

class chafa.Placement(image: Image, id: int = 0)

This class defines the placement of an Image on a Canvas.

Note

None of placement’s properties have any effect if the Canvas’s pixel mode is set to PixelMode.CHAFA_PIXEL_MODE_SYMBOLS.

Parameters:

  • image – The Image to be placed.

  • id – An id to assign to the image. Leave as 0 to assign one automatically.

Added in version 1.2.0.

property tuck
Type:

Tuck

This describes how the Image is resized to fit on the Canvas, and defaults to Tuck.CHAFA_TUCK_STRETCH.

property halign
Type:

Align

Describes the horizontal alignment of the Image on the Canvas.

property valign
Type:

Align

Describes the horizontal alignment of the Image on the Canvas.