github.com/SkycoinProject/gomobile@v0.0.0-20190312151609-d3739f865fa6/example/flappy/main.go (about)

     1  // Copyright 2015 The Go Authors. All rights reserved.
     2  // Use of this source code is governed by a BSD-style
     3  // license that can be found in the LICENSE file.
     4  
     5  // +build darwin linux
     6  
     7  // Flappy Gopher is a simple one-button game that uses the
     8  // mobile framework and the experimental sprite engine.
     9  package main
    10  
    11  import (
    12  	"math/rand"
    13  	"time"
    14  
    15  	"golang.org/x/mobile/app"
    16  	"golang.org/x/mobile/event/key"
    17  	"golang.org/x/mobile/event/lifecycle"
    18  	"golang.org/x/mobile/event/paint"
    19  	"golang.org/x/mobile/event/size"
    20  	"golang.org/x/mobile/event/touch"
    21  	"golang.org/x/mobile/exp/gl/glutil"
    22  	"golang.org/x/mobile/exp/sprite"
    23  	"golang.org/x/mobile/exp/sprite/clock"
    24  	"golang.org/x/mobile/exp/sprite/glsprite"
    25  	"golang.org/x/mobile/gl"
    26  )
    27  
    28  func main() {
    29  	rand.Seed(time.Now().UnixNano())
    30  
    31  	app.Main(func(a app.App) {
    32  		var glctx gl.Context
    33  		var sz size.Event
    34  		for e := range a.Events() {
    35  			switch e := a.Filter(e).(type) {
    36  			case lifecycle.Event:
    37  				switch e.Crosses(lifecycle.StageVisible) {
    38  				case lifecycle.CrossOn:
    39  					glctx, _ = e.DrawContext.(gl.Context)
    40  					onStart(glctx)
    41  					a.Send(paint.Event{})
    42  				case lifecycle.CrossOff:
    43  					onStop()
    44  					glctx = nil
    45  				}
    46  			case size.Event:
    47  				sz = e
    48  			case paint.Event:
    49  				if glctx == nil || e.External {
    50  					continue
    51  				}
    52  				onPaint(glctx, sz)
    53  				a.Publish()
    54  				a.Send(paint.Event{}) // keep animating
    55  			case touch.Event:
    56  				if down := e.Type == touch.TypeBegin; down || e.Type == touch.TypeEnd {
    57  					game.Press(down)
    58  				}
    59  			case key.Event:
    60  				if e.Code != key.CodeSpacebar {
    61  					break
    62  				}
    63  				if down := e.Direction == key.DirPress; down || e.Direction == key.DirRelease {
    64  					game.Press(down)
    65  				}
    66  			}
    67  		}
    68  	})
    69  }
    70  
    71  var (
    72  	startTime = time.Now()
    73  	images    *glutil.Images
    74  	eng       sprite.Engine
    75  	scene     *sprite.Node
    76  	game      *Game
    77  )
    78  
    79  func onStart(glctx gl.Context) {
    80  	images = glutil.NewImages(glctx)
    81  	eng = glsprite.Engine(images)
    82  	game = NewGame()
    83  	scene = game.Scene(eng)
    84  }
    85  
    86  func onStop() {
    87  	eng.Release()
    88  	images.Release()
    89  	game = nil
    90  }
    91  
    92  func onPaint(glctx gl.Context, sz size.Event) {
    93  	glctx.ClearColor(1, 1, 1, 1)
    94  	glctx.Clear(gl.COLOR_BUFFER_BIT)
    95  	now := clock.Time(time.Since(startTime) * 60 / time.Second)
    96  	game.Update(now)
    97  	eng.Render(scene, now, sz)
    98  }