mirror of
https://github.com/hajimehoshi/ebiten.git
synced 2024-11-10 04:57:26 +01:00
100 lines
2.0 KiB
Go
100 lines
2.0 KiB
Go
// Copyright 2016 The Ebiten Authors
|
|
//
|
|
// Licensed under the Apache License, Version 2.0 (the "License");
|
|
// you may not use this file except in compliance with the License.
|
|
// You may obtain a copy of the License at
|
|
//
|
|
// http://www.apache.org/licenses/LICENSE-2.0
|
|
//
|
|
// Unless required by applicable law or agreed to in writing, software
|
|
// distributed under the License is distributed on an "AS IS" BASIS,
|
|
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
// See the License for the specific language governing permissions and
|
|
// limitations under the License.
|
|
|
|
// +build example
|
|
|
|
package main
|
|
|
|
import (
|
|
"fmt"
|
|
_ "image/png"
|
|
"log"
|
|
|
|
"github.com/hajimehoshi/ebiten"
|
|
"github.com/hajimehoshi/ebiten/ebitenutil"
|
|
)
|
|
|
|
const (
|
|
screenWidth = 320
|
|
screenHeight = 240
|
|
)
|
|
|
|
var (
|
|
bgImage *ebiten.Image
|
|
)
|
|
|
|
func init() {
|
|
var err error
|
|
bgImage, _, err = ebitenutil.NewImageFromFile("_resources/images/tile.png", ebiten.FilterDefault)
|
|
if err != nil {
|
|
log.Fatal(err)
|
|
}
|
|
}
|
|
|
|
var (
|
|
theViewport = &viewport{}
|
|
)
|
|
|
|
type viewport struct {
|
|
x16 int
|
|
y16 int
|
|
}
|
|
|
|
func (p *viewport) Move() {
|
|
w, h := bgImage.Size()
|
|
maxX16 := w * 16
|
|
maxY16 := h * 16
|
|
|
|
p.x16 += w / 32
|
|
p.y16 += h / 32
|
|
p.x16 %= maxX16
|
|
p.y16 %= maxY16
|
|
}
|
|
|
|
func (p *viewport) Position() (int, int) {
|
|
return p.x16, p.y16
|
|
}
|
|
|
|
func update(screen *ebiten.Image) error {
|
|
theViewport.Move()
|
|
|
|
if ebiten.IsRunningSlowly() {
|
|
return nil
|
|
}
|
|
|
|
x16, y16 := theViewport.Position()
|
|
offsetX, offsetY := float64(-x16)/16, float64(-y16)/16
|
|
|
|
// Draw bgImage on the screen repeatedly.
|
|
const repeat = 3
|
|
w, h := bgImage.Size()
|
|
for j := 0; j < repeat; j++ {
|
|
for i := 0; i < repeat; i++ {
|
|
op := &ebiten.DrawImageOptions{}
|
|
op.GeoM.Translate(float64(w*i), float64(h*j))
|
|
op.GeoM.Translate(offsetX, offsetY)
|
|
screen.DrawImage(bgImage, op)
|
|
}
|
|
}
|
|
|
|
ebitenutil.DebugPrint(screen, fmt.Sprintf("FPS: %0.2f", ebiten.CurrentFPS()))
|
|
return nil
|
|
}
|
|
|
|
func main() {
|
|
if err := ebiten.Run(update, screenWidth, screenHeight, 2, "Infinite Scroll (Ebiten Demo)"); err != nil {
|
|
log.Fatal(err)
|
|
}
|
|
}
|