mirror of
https://github.com/hajimehoshi/ebiten.git
synced 2024-11-10 13:07:26 +01:00
169 lines
5.3 KiB
HTML
169 lines
5.3 KiB
HTML
<!DOCTYPE html>
|
|
<script src="../scripts/force-https.js"></script>
|
|
<link rel="shortcut icon" href="../favicon.png" type="image/png" >
|
|
<link rel="icon" href="../favicon.png" type="image/png" >
|
|
<title>Ebiten example - masking</title>
|
|
<link rel="stylesheet" href="../stylesheets/bootstrap.min.css">
|
|
<link rel="stylesheet" href="../stylesheets/highlight-github.css">
|
|
<link rel="stylesheet" href="../stylesheets/ebiten.css">
|
|
<script src="./scripts/googleanalytics.js"></script>
|
|
|
|
<header class="navbar"><div class="container">
|
|
<div class="navbar-header">
|
|
<a class="navbar-brand" href="..">Ebiten</a>
|
|
</div>
|
|
<nav class="collapse navbar-collapse">
|
|
<ul class="nav navbar-nav navbar-right">
|
|
<li><a href="https://github.com/hajimehoshi/ebiten">GitHub</a></li>
|
|
<li><a href="https://godoc.org/github.com/hajimehoshi/ebiten">GoDoc</a></li>
|
|
<li><a href="https://github.com/hajimehoshi/ebiten/wiki">Wiki</a>
|
|
</ul>
|
|
</nav>
|
|
</header>
|
|
|
|
<main><div class="container">
|
|
|
|
<h2>Ebiten example - masking</h2>
|
|
<iframe src="masking.content.html" width="640" height="480"></iframe>
|
|
<pre><code class="language-go">// +build example
|
|
|
|
package main
|
|
|
|
import (
|
|
"image"
|
|
"image/color"
|
|
_ "image/jpeg"
|
|
"log"
|
|
"math"
|
|
|
|
"github.com/hajimehoshi/ebiten"
|
|
"github.com/hajimehoshi/ebiten/ebitenutil"
|
|
)
|
|
|
|
const (
|
|
screenWidth = 320
|
|
screenHeight = 240
|
|
)
|
|
|
|
var (
|
|
gophersImage *ebiten.Image
|
|
fiveyearsImage *ebiten.Image
|
|
maskImage *ebiten.Image
|
|
spotLightImage *ebiten.Image
|
|
spotLightX = 0
|
|
spotLightY = 0
|
|
spotLightVX = 1
|
|
spotLightVY = 1
|
|
)
|
|
|
|
func update(screen *ebiten.Image) error {
|
|
spotLightX += spotLightVX
|
|
spotLightY += spotLightVY
|
|
if spotLightX < 0 {
|
|
spotLightX = -spotLightX
|
|
spotLightVX = -spotLightVX
|
|
}
|
|
if spotLightY < 0 {
|
|
spotLightY = -spotLightY
|
|
spotLightVY = -spotLightVY
|
|
}
|
|
w, h := spotLightImage.Size()
|
|
maxX, maxY := screenWidth-w, screenHeight-h
|
|
if maxX < spotLightX {
|
|
spotLightX = -spotLightX + 2*maxX
|
|
spotLightVX = -spotLightVX
|
|
}
|
|
if maxY < spotLightY {
|
|
spotLightY = -spotLightY + 2*maxY
|
|
spotLightVY = -spotLightVY
|
|
}
|
|
|
|
if err := maskImage.Clear(); err != nil {
|
|
return err
|
|
}
|
|
|
|
op := &ebiten.DrawImageOptions{}
|
|
op.GeoM.Translate(float64(spotLightX), float64(spotLightY))
|
|
if err := maskImage.DrawImage(spotLightImage, op); err != nil {
|
|
return err
|
|
}
|
|
|
|
op = &ebiten.DrawImageOptions{}
|
|
op.CompositeMode = ebiten.CompositeModeSourceOut
|
|
if err := maskImage.DrawImage(fiveyearsImage, op); err != nil {
|
|
return err
|
|
}
|
|
|
|
if err := screen.Fill(color.RGBA{0x00, 0x00, 0x80, 0xff}); err != nil {
|
|
return err
|
|
}
|
|
if err := screen.DrawImage(gophersImage, &ebiten.DrawImageOptions{}); err != nil {
|
|
return err
|
|
}
|
|
if err := screen.DrawImage(maskImage, &ebiten.DrawImageOptions{}); err != nil {
|
|
return err
|
|
}
|
|
|
|
return nil
|
|
}
|
|
|
|
func max(a, b int) int {
|
|
if a < b {
|
|
return b
|
|
}
|
|
return a
|
|
}
|
|
|
|
func min(a, b int) int {
|
|
if a < b {
|
|
return a
|
|
}
|
|
return b
|
|
}
|
|
|
|
func main() {
|
|
var err error
|
|
gophersImage, _, err = ebitenutil.NewImageFromFile("_resources/images/gophers.jpg", ebiten.FilterNearest)
|
|
if err != nil {
|
|
log.Fatal(err)
|
|
}
|
|
fiveyearsImage, _, err = ebitenutil.NewImageFromFile("_resources/images/fiveyears.jpg", ebiten.FilterNearest)
|
|
if err != nil {
|
|
log.Fatal(err)
|
|
}
|
|
maskImage, err = ebiten.NewImage(screenWidth, screenHeight, ebiten.FilterNearest)
|
|
if err != nil {
|
|
log.Fatal(err)
|
|
}
|
|
|
|
as := image.Point{128, 128}
|
|
a := image.NewAlpha(image.Rectangle{image.ZP, as})
|
|
for j := 0; j < as.Y; j++ {
|
|
for i := 0; i < as.X; i++ {
|
|
r := as.X / 2
|
|
d := math.Sqrt(float64((i-r)*(i-r) + (j-r)*(j-r)))
|
|
b := uint8(max(0, min(0xff, 3*0xff-int(d*3*0xff)/r)))
|
|
a.SetAlpha(i, j, color.Alpha{b})
|
|
}
|
|
}
|
|
spotLightImage, err = ebiten.NewImageFromImage(a, ebiten.FilterNearest)
|
|
if err != nil {
|
|
log.Fatal(err)
|
|
}
|
|
if err := ebiten.Run(update, screenWidth, screenHeight, 2, "Masking (Ebiten Demo)"); err != nil {
|
|
log.Fatal(err)
|
|
}
|
|
}
|
|
</code></pre>
|
|
|
|
</div></main>
|
|
|
|
<footer><div class="container">
|
|
<p>© 2013 Hajime Hoshi</p>
|
|
<p>Code is licensed under <a href="https://github.com/hajimehoshi/ebiten/blob/master/LICENSE">the Apache License 2.0</a>.</p>
|
|
<p>The content of this page is licensed under <a href="https://creativecommons.org/licenses/by/4.0/">the Creative Commons Attribution 4.0 License</a>.</p>
|
|
</div></footer>
|
|
|
|
<script src="../scripts/highlight.pack.js"></script>
|
|
<script>hljs.initHighlightingOnLoad();</script>
|