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Golang.org/x/image/draw

As explained in Learn Go with Pocket-Sized Projects

golang.org/x/image/draw is a Go image-drawing package that provides scaling and interpolation operations beyond the standard image/draw package.

golang.org/x/image/draw extends Go’s standard image/draw package with image scaling and interpolation. Its Scaler interface shrinks or expands a rectangle from an input image into an output rectangle. section 9.6.2

Available Scaler implementations include:

  • NearestNeighbor, which preserves sharp pixel edges. section 9.6.2
  • CatmullRom and ApproxBiLinear, which provide alternative interpolation behavior. section 9.6.2

Scaling a maze frame into a GIF

Create a paletted frame with the maze’s aspect ratio, then call draw.NearestNeighbor.Scale(frame, frame.Rect, s.maze, s.maze.Bounds(), draw.Over, nil). Repeating this for explored-maze states produces animation frames.

How Learn Go with Pocket-Sized Projects covers it

How deep it goes
Defines the Scaler interface and implementations, then demonstrates one concrete Scale call without detailing interpolation internals.
Examples
Uses a 500-pixel-wide paletted maze frame and NearestNeighbor scaling to generate approximately 30 exploration frames.
What it assumes
Assumes familiarity with Go images and rectangles while demonstrating package selection and a working scaling operation.
What you can do after
Build it from scratch by scaling image regions into output frames for a pixel-preserving animation.
How it connects
Connects image scaling with image/draw, paletted images, GIF generation, interpolation, and pixel-based maze animation.
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