spritesheet.go

package ebitenloader

import (
	"image"

	"github.com/hajimehoshi/ebiten/v2"
)

// ParseSprites parses a spritesheet into an array of it's sub-sprites.
//
// spN - number of sprites you want to parse
//
// spWidth & spHeight - dimensions of each individual sprite in pixels
//
// sheetWidth - width of the spritesheet measured in sprite lengths
func ParseSprites(src *ebiten.Image, spN, spWidth, spHeight, sheetWidth int) []*ebiten.Image {
	var sprites []*ebiten.Image

	for i := range spN {
		column := i % sheetWidth
		row := i / sheetWidth

		x0 := column * spWidth
		y0 := row * spHeight
		x1 := x0 + spWidth
		y1 := y0 + spHeight

		rect := image.Rect(x0, y0, x1, y1)

		subImg := src.SubImage(rect).(*ebiten.Image)
		sprites = append(sprites, subImg)
	}

	return sprites
}