ordoor/internal/assetstore/object.go

package assetstore

import (
	"log"

	"github.com/hajimehoshi/ebiten"

	"code.ur.gs/lupine/ordoor/internal/data"
)

type Object struct {
	assets  *AssetStore
	sprites []*Sprite

	raw *data.Object
}

type Sprite struct {
	obj *Object

	XOffset int
	YOffset int
	Width   int
	Height  int

	Image *ebiten.Image
}

func (a *AssetStore) Object(name string) (*Object, error) {
	name = canonical(name)

	if obj, ok := a.objs[name]; ok {
		return obj, nil
	}
	log.Printf("Loading object %v", name)

	filename, err := a.lookup(name, "obj", "Obj")
	if err != nil {
		return nil, err
	}

	raw, err := data.LoadObjectLazily(filename)
	if err != nil {
		return nil, err
	}
	raw.Name = name

	obj := &Object{
		assets:  a,
		sprites: make([]*Sprite, int(raw.NumSprites)),
		raw:     raw,
	}
	a.objs[name] = obj

	return obj, nil
}

// Filled lazily
func (o *Object) Sprite(idx int) (*Sprite, error) {
	if sprite := o.sprites[idx]; sprite != nil {
		return sprite, nil
	}
	log.Printf("Loading sprite %v:%v", o.raw.Name, idx)

	if o.raw.Sprites[idx] == nil {
		if err := o.raw.LoadSprite(idx); err != nil {
			return nil, err
		}
	}

	raw := o.raw.Sprites[idx]
	img, err := ebiten.NewImageFromImage(raw.ToImage(), ebiten.FilterDefault)
	if err != nil {
		return nil, err
	}

	sprite := &Sprite{
		obj:     o,
		Width:   int(raw.Width),
		Height:  int(raw.Width),
		XOffset: int(raw.XOffset),
		YOffset: int(raw.YOffset),
		Image:   img,
	}

	o.sprites[idx] = sprite

	return sprite, nil
}