Bitmaps

Doodle provides methods to load bitmaps and convert them into pictures. This support is very dependent on the backend, so consult the documentation for the backends you use to see the specifics of what is available.

Loading Bitmaps

The functionality to load bitmaps is provided by the LoadBitmap algebra. It is parameterized by two types:

1. the Specifier type, which is used to specify where the bitmap is found; and
2. the Bitmap type, which is the type of the bitmap that will be loaded.

For example, on the JVM the specifier can be either a File or a Path and the bitmap type is a BufferedImage. However, for the Canvas backend the specifier is a String URL while the bitmap type can be a HTMLImageElement or a ImageBitmap.

The idiomatic way to load a bitmap is by importing doodle.syntax.all.* and calling loadBitmap on a method. Here's an example for the Java2d backend, using a File.

import doodle.syntax.all.*
import doodle.java2d.{*, given}

import java.io.File

File("/path/to/bitmap.png").loadBitmap

The result is an IO containing the bitmap type, which in this case is BufferedImage.

Converting Bitmaps to Pictures

A bitmap can be converted to a Picture by calling the toPicture method. To load and convert a bitmap in one call, use the loadToPicture. The example below shows both methods in use.

import doodle.syntax.all.*
import doodle.java2d.{*, given}

import java.io.File
// Convert to a Picture in two steps
File("/path/to/bitmap.png").loadBitmap.toPicture

// Load and convert to Picture in one step
File("/path/to/bitmap.png").loadToPicture

This functionality is provided by instances of the ToPicture algebra, which provides a generic way to convert types to Picture.

Implementation

This functionality is backend specific and is not available on Image.