mirror of
https://github.com/hajimehoshi/ebiten.git
synced 2024-12-24 18:58:54 +01:00
Add example 'masking' (#39)
This commit is contained in:
parent
568dbe9603
commit
1eb623cf16
BIN
examples/_resources/images/fiveyears.jpg
Normal file
BIN
examples/_resources/images/fiveyears.jpg
Normal file
Binary file not shown.
After Width: | Height: | Size: 31 KiB |
@ -28,14 +28,26 @@ Email: info@9031.com
|
||||
http://www.sozai-page.com/02_sozai/b/b04/b04_002/b04_002.html
|
||||
```
|
||||
|
||||
## fiveyears.jpg
|
||||
|
||||
```
|
||||
The Go gopher was designed by Renee French. (http://reneefrench.blogspot.com/)
|
||||
The design is licensed under the Creative Commons 3.0 Attributions license.
|
||||
Read this article for more details: https://blog.golang.org/gopher
|
||||
```
|
||||
|
||||
## gophers.jpg
|
||||
|
||||
```
|
||||
http://blog.golang.org/go-programming-language-turns-two
|
||||
|
||||
Photograph by Chris Nokleberg
|
||||
the Creative Commons Attribution 3.0 License
|
||||
```
|
||||
|
||||
## Other image files
|
||||
|
||||
```
|
||||
Creative Commons Attribution 3.0 License
|
||||
Copyright 2014 Hajime Hoshi
|
||||
the Creative Commons Attribution 3.0 License
|
||||
```
|
||||
|
141
examples/masking/main.go
Normal file
141
examples/masking/main.go
Normal file
@ -0,0 +1,141 @@
|
||||
// Copyright 2016 Hajime Hoshi
|
||||
//
|
||||
// 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.
|
||||
|
||||
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.CompositionMode = ebiten.CompositionModeSourceOut
|
||||
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)
|
||||
}
|
||||
}
|
12
graphics.go
12
graphics.go
@ -39,7 +39,19 @@ func glFilter(c *opengl.Context, filter Filter) opengl.Filter {
|
||||
// CompositionMode represents Porter-Duff composition mode.
|
||||
type CompositionMode int
|
||||
|
||||
// Note: This name convention follow CSS compositing: https://drafts.fxtf.org/compositing-2/
|
||||
|
||||
const (
|
||||
CompositionModeSourceOver CompositionMode = CompositionMode(opengl.CompositionModeSourceOver) // regular alpha blending
|
||||
CompositionModeClear = CompositionMode(opengl.CompositionModeClear)
|
||||
CompositionModeCopy = CompositionMode(opengl.CompositionModeCopy)
|
||||
CompositionModeDestination = CompositionMode(opengl.CompositionModeDestination)
|
||||
CompositionModeSourceIn = CompositionMode(opengl.CompositionModeSourceIn)
|
||||
CompositionModeDestinationIn = CompositionMode(opengl.CompositionModeDestinationIn)
|
||||
CompositionModeSourceOut = CompositionMode(opengl.CompositionModeSourceOut)
|
||||
CompositionModeDestinationOut = CompositionMode(opengl.CompositionModeDestinationOut)
|
||||
CompositionModeSourceAtop = CompositionMode(opengl.CompositionModeSourceAtop)
|
||||
CompositionModeDestinationAtop = CompositionMode(opengl.CompositionModeDestinationAtop)
|
||||
CompositionModeXor = CompositionMode(opengl.CompositionModeXor)
|
||||
CompositionModeLighter = CompositionMode(opengl.CompositionModeLighter) // sum of source and destination (a.k.a. 'plus' or 'additive')
|
||||
)
|
||||
|
@ -47,8 +47,8 @@ const (
|
||||
CompositionModeSourceOver CompositionMode = iota // This value must be 0 (= initial value)
|
||||
CompositionModeClear
|
||||
CompositionModeCopy
|
||||
CompositionModeDesination
|
||||
CompositionModeDesinationOver
|
||||
CompositionModeDestination
|
||||
CompositionModeDestinationOver
|
||||
CompositionModeSourceIn
|
||||
CompositionModeDestinationIn
|
||||
CompositionModeSourceOut
|
||||
@ -68,10 +68,10 @@ func (c *Context) operations(mode CompositionMode) (src operation, dst operation
|
||||
return c.zero, c.zero
|
||||
case CompositionModeCopy:
|
||||
return c.one, c.zero
|
||||
case CompositionModeDesination:
|
||||
case CompositionModeDestination:
|
||||
return c.zero, c.one
|
||||
case CompositionModeDesinationOver:
|
||||
return c.one, c.oneMinusDstAlpha
|
||||
case CompositionModeDestinationOver:
|
||||
return c.oneMinusDstAlpha, c.one
|
||||
case CompositionModeSourceIn:
|
||||
return c.dstAlpha, c.zero
|
||||
case CompositionModeDestinationIn:
|
||||
|
Loading…
Reference in New Issue
Block a user