groovy/examples/splashmenu/scenes/splash.go

package splashmenu

import (
	"cosmos/diego/groovy"
	"image/color"
	"log"

	"github.com/hajimehoshi/ebiten/v2"
	"github.com/hajimehoshi/ebiten/v2/examples/resources/fonts"
	"github.com/hajimehoshi/ebiten/v2/text"
	"golang.org/x/image/font"
	"golang.org/x/image/font/opentype"
)

var (
	splashFont font.Face
)

func init() {
	tt, err := opentype.Parse(fonts.PressStart2P_ttf)
	if err != nil {
		log.Fatal(err)
	}

	const dpi = 72
	splashFont, err = opentype.NewFace(tt, &opentype.FaceOptions{
		Size:    12,
		DPI:     dpi,
		Hinting: font.HintingVertical,
	})
	if err != nil {
		log.Fatal(err)
	}
}

type Splash struct {
	bgcolor   color.RGBA
	increment int
	events    map[groovy.SceneEvent]func()
}

// GetSceneEvents implements groovy.Scene.
func (*Splash) GetSceneEvents() []groovy.SceneEvent {
	return nil
}

func NewSplash() Splash {
	return Splash{
		bgcolor: color.RGBA{0xFF, 0xFF, 0xFF, 0xFF},
		events:  make(map[groovy.SceneEvent]func()),
	}
}

func (s *Splash) Draw(screen *ebiten.Image) {
	screen.Fill(s.bgcolor)
	text.Draw(screen, "splash", splashFont, 40, 40, color.White)
}

func (s *Splash) Update() error {
	s.increment++

	s.bgcolor.R = (s.bgcolor.R - 2) % 0xFF
	s.bgcolor.G = (s.bgcolor.G - 2) % 0xFF
	s.bgcolor.B = (s.bgcolor.B - 2) % 0xFF

	if s.bgcolor.R == 0x00 {
		s.events[groovy.COMPLETED]()
	}

	return nil
}

func (s Splash) SetEventHandler(event groovy.SceneEvent, f func()) {
	s.events[event] = f
}