ebiten/examples/moire/main.go
Hajime Hoshi 237498e51f
ui: Add an optional function Draw function to Game interface (#1107)
This change adds an optional function Draw to the Game interface.
With Draw function, the game logic and rendering are separate.
There are some benefits:

  * The API is clearer and easier to understand.
  * When TPS < FPS, smoother rendering can be performed without
    changing the game logic depending on TPS.
  * Porting to XNA, which has separate functions Update and Draw,
    would be a little easier.

Draw is optional due to backward compatibility. Game interface was
already used before v1.11.x in mobile packages, and adding a
function would break existing code unfortunately. Then, we adopted
switching the behavior based on whether Draw is implemented or not
by type assertions.

IsDrawingSkipped will always return false when Draw is implemented.

Fixes #1104
2020-03-24 12:01:37 +09:00

107 lines
2.4 KiB
Go

// Copyright 2017 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 jsgo
// This example is just to check if Ebiten can draw fine checker pattern evenly.
// If there is something wrong in the implementation, the result might include
// uneven patterns (#459).
package main
import (
"log"
"github.com/hajimehoshi/ebiten"
"github.com/hajimehoshi/ebiten/inpututil"
)
const (
screenWidth = 640
screenHeight = 480
initScreenScale = 1
)
var (
dots []byte
dotsWidth int
dotsHeight int
)
func getDots(width, height int) []byte {
if dotsWidth == width && dotsHeight == height {
return dots
}
dotsWidth = width
dotsHeight = height
dots = make([]byte, width*height*4)
for j := 0; j < height; j++ {
for i := 0; i < width; i++ {
if (i+j)%2 == 0 {
dots[(i+j*width)*4+0] = 0xff
dots[(i+j*width)*4+1] = 0xff
dots[(i+j*width)*4+2] = 0xff
dots[(i+j*width)*4+3] = 0xff
}
}
}
return dots
}
type game struct {
scale float64
}
func (g *game) Layout(outsideWidth, outsideHeight int) (int, int) {
return screenWidth, screenHeight
}
func (g *game) Update(screen *ebiten.Image) error {
fullscreen := ebiten.IsFullscreen()
if inpututil.IsKeyJustPressed(ebiten.KeyS) {
switch g.scale {
case 1:
g.scale = 1.5
case 1.5:
g.scale = 2
case 2:
g.scale = 1
default:
panic("not reached")
}
ebiten.SetWindowSize(int(screenWidth*g.scale), int(screenHeight*g.scale))
}
if inpututil.IsKeyJustPressed(ebiten.KeyF) {
fullscreen = !fullscreen
ebiten.SetFullscreen(fullscreen)
}
return nil
}
func (g *game) Draw(screen *ebiten.Image) {
screen.ReplacePixels(getDots(screen.Size()))
}
func main() {
g := &game{
scale: initScreenScale,
}
ebiten.SetWindowSize(screenWidth*initScreenScale, screenHeight*initScreenScale)
ebiten.SetWindowTitle("Moire (Ebiten Demo)")
ebiten.SetWindowResizable(true)
if err := ebiten.RunGame(g); err != nil {
log.Fatal(err)
}
}