mirror of
https://github.com/hajimehoshi/ebiten.git
synced 2024-09-20 13:22:19 +02:00
119 lines
3.3 KiB
Go
119 lines
3.3 KiB
Go
// Copyright 2018 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 an experiment to minify images with various filters.
|
|
// When linear filter is used, mipmap images should be used for high-quality rendering (#578).
|
|
|
|
package main
|
|
|
|
import (
|
|
"bytes"
|
|
"fmt"
|
|
"image"
|
|
_ "image/jpeg"
|
|
"log"
|
|
"math"
|
|
|
|
"github.com/hajimehoshi/ebiten"
|
|
"github.com/hajimehoshi/ebiten/ebitenutil"
|
|
"github.com/hajimehoshi/ebiten/examples/resources/images"
|
|
"github.com/hajimehoshi/ebiten/inpututil"
|
|
)
|
|
|
|
const (
|
|
screenWidth = 800
|
|
screenHeight = 480
|
|
)
|
|
|
|
var (
|
|
gophersImage *ebiten.Image
|
|
rotate = false
|
|
clip = false
|
|
counter = 0
|
|
)
|
|
|
|
func update(screen *ebiten.Image) error {
|
|
counter++
|
|
if counter == 480 {
|
|
counter = 0
|
|
}
|
|
|
|
if inpututil.IsKeyJustPressed(ebiten.KeyR) {
|
|
rotate = !rotate
|
|
}
|
|
if inpututil.IsKeyJustPressed(ebiten.KeyC) {
|
|
clip = !clip
|
|
}
|
|
|
|
if ebiten.IsDrawingSkipped() {
|
|
return nil
|
|
}
|
|
|
|
s := 1.5 / math.Pow(1.01, float64(counter))
|
|
msg := fmt.Sprintf(`Minifying images (Nearest filter vs Linear filter):
|
|
Press R to rotate the images.
|
|
Press C to clip the images.
|
|
Scale: %0.2f`, s)
|
|
ebitenutil.DebugPrint(screen, msg)
|
|
|
|
clippedGophersImage := gophersImage.SubImage(image.Rect(100, 100, 200, 200)).(*ebiten.Image)
|
|
for i, f := range []ebiten.Filter{ebiten.FilterNearest, ebiten.FilterLinear} {
|
|
w, h := gophersImage.Size()
|
|
|
|
op := &ebiten.DrawImageOptions{}
|
|
if rotate {
|
|
op.GeoM.Translate(-float64(w)/2, -float64(h)/2)
|
|
op.GeoM.Rotate(float64(counter) / 300 * 2 * math.Pi)
|
|
op.GeoM.Translate(float64(w)/2, float64(h)/2)
|
|
}
|
|
op.GeoM.Scale(s, s)
|
|
op.GeoM.Translate(32+float64(i*w)*s+float64(i*4), 64)
|
|
op.Filter = f
|
|
if clip {
|
|
screen.DrawImage(clippedGophersImage, op)
|
|
} else {
|
|
screen.DrawImage(gophersImage, op)
|
|
}
|
|
}
|
|
|
|
return nil
|
|
}
|
|
|
|
func main() {
|
|
// Decode image from a byte slice instead of a file so that
|
|
// this example works in any working directory.
|
|
// If you want to use a file, there are some options:
|
|
// 1) Use os.Open and pass the file to the image decoder.
|
|
// This is a very regular way, but doesn't work on browsers.
|
|
// 2) Use ebitenutil.OpenFile and pass the file to the image decoder.
|
|
// This works even on browsers.
|
|
// 3) Use ebitenutil.NewImageFromFile to create an ebiten.Image directly from a file.
|
|
// This also works on browsers.
|
|
img, _, err := image.Decode(bytes.NewReader(images.Gophers_jpg))
|
|
if err != nil {
|
|
log.Fatal(err)
|
|
}
|
|
|
|
// Specifying filter on NewImage[FromImage] is just for backward compatibility.
|
|
// Now specifying filter at DrawImageOptions is recommended.
|
|
// Specify FilterDefault here, that means to prefer filter specified at DrawImageOptions.
|
|
gophersImage, _ = ebiten.NewImageFromImage(img, ebiten.FilterDefault)
|
|
|
|
if err := ebiten.Run(update, screenWidth, screenHeight, 1, "Minify (Ebiten Demo)"); err != nil {
|
|
log.Fatal(err)
|
|
}
|
|
}
|