Add example mosaic

example/mosaic/main.go

@@ -0,0 +1,64 @@
+/*
+Copyright 2014 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 (
+	"github.com/hajimehoshi/ebiten"
+	"github.com/hajimehoshi/ebiten/ebitenutil"
+	_ "image/jpeg"
+	"log"
+)
+
+const (
+	screenWidth  = 320
+	screenHeight = 240
+)
+
+const mosaicRatio = 16
+
+type Game struct {
+	gophersTexture      *ebiten.Texture
+	gophersRenderTarget *ebiten.RenderTarget
+}
+
+func (g *Game) Update(gr ebiten.GraphicsContext) error {
+	gr.PushRenderTarget(g.gophersRenderTarget)
+	geo := ebiten.ScaleGeometry(1.0/mosaicRatio, 1.0/mosaicRatio)
+	ebiten.DrawWholeTexture(gr, g.gophersTexture, geo, ebiten.ColorMatrixI())
+	gr.PopRenderTarget()
+
+	geo = ebiten.ScaleGeometry(mosaicRatio/2.0, mosaicRatio/2.0)
+	ebiten.DrawWholeTexture(gr, g.gophersRenderTarget.Texture(), geo, ebiten.ColorMatrixI())
+	return nil
+}
+
+func main() {
+	g := new(Game)
+	var err error
+	g.gophersTexture, _, err = ebitenutil.NewTextureFromFile("images/gophers.jpg", ebiten.FilterNearest)
+	if err != nil {
+		log.Fatal(err)
+	}
+	w, h := g.gophersTexture.Size()
+	g.gophersRenderTarget, err = ebiten.NewRenderTarget(w/mosaicRatio, h/mosaicRatio, ebiten.FilterNearest)
+	if err != nil {
+		log.Fatal(err)
+	}
+	if err := ebiten.Run(g.Update, screenWidth, screenHeight, 2, "Mosaic (Ebiten Demo)"); err != nil {
+		log.Fatal(err)
+	}
+}