Files
ebiten/examples/minify/main.go
2025-03-29 19:33:23 +09:00

139 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.
// 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"
"image"
_ "image/jpeg"
"log"
"math"
"github.com/ebitengine/debugui"
"github.com/hajimehoshi/ebiten/v2"
"github.com/hajimehoshi/ebiten/v2/examples/resources/images"
)
const (
screenWidth = 1000
screenHeight = 640
)
var (
gophersImage *ebiten.Image
)
type Game struct {
debugui debugui.DebugUI
rotate bool
clip bool
autoScale bool
counter int
scale float64
}
func (g *Game) Update() error {
if g.scale == 0 {
g.scale = 1
}
g.counter++
if g.counter == 480 {
g.counter = 0
}
if g.autoScale {
g.scale = 1.5 / math.Pow(1.01, float64(g.counter))
}
if _, err := g.debugui.Update(func(ctx *debugui.Context) error {
ctx.Window("Control", image.Rect(10, 10, 260, 160), func(layout debugui.ContainerLayout) {
ctx.SetGridLayout([]int{-1, -2}, nil)
ctx.Text("Rotate")
ctx.Checkbox(&g.rotate, "")
ctx.Text("Clip")
ctx.Checkbox(&g.clip, "")
ctx.Text("Scale")
ctx.SliderF(&g.scale, 0.01, 2, 0.01, 2)
ctx.Text("Auto Scale")
ctx.Checkbox(&g.autoScale, "")
})
ctx.Window("Info", image.Rect(270, 10, 520, 160), func(layout debugui.ContainerLayout) {
ctx.Text("Minifying Images\nLeft: Nearest filter\nCenter: Linear filter (w/ mipmaps)\nRight: Linear Filter (w/o mipmaps)")
})
return nil
}); err != nil {
return err
}
return nil
}
func (g *Game) Draw(screen *ebiten.Image) {
s := g.scale
clippedGophersImage := gophersImage.SubImage(image.Rect(100, 100, 200, 200)).(*ebiten.Image)
for i := range 3 {
w, h := gophersImage.Bounds().Dx(), gophersImage.Bounds().Dy()
op := &ebiten.DrawImageOptions{}
if g.rotate {
op.GeoM.Translate(-float64(w)/2, -float64(h)/2)
op.GeoM.Rotate(float64(g.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), 200)
if i == 0 {
op.Filter = ebiten.FilterNearest
} else {
op.Filter = ebiten.FilterLinear
}
if i == 2 {
op.DisableMipmaps = true
}
if g.clip {
screen.DrawImage(clippedGophersImage, op)
} else {
screen.DrawImage(gophersImage, op)
}
}
g.debugui.Draw(screen)
}
func (g *Game) Layout(outsideWidth, outsideHeight int) (int, int) {
return screenWidth, screenHeight
}
func main() {
// Decode an image from the image file's byte slice.
img, _, err := image.Decode(bytes.NewReader(images.Gophers_jpg))
if err != nil {
log.Fatal(err)
}
gophersImage = ebiten.NewImageFromImage(img)
ebiten.SetWindowSize(screenWidth, screenHeight)
ebiten.SetWindowTitle("Minify (Ebitengine Demo)")
if err := ebiten.RunGame(&Game{}); err != nil {
log.Fatal(err)
}
}