vendor: Add dependencies for discosrv

vendor/github.com/cznic/mathutil/example2/example2.go

@@ -0,0 +1,66 @@
+// Copyright (c) 2011 CZ.NIC z.s.p.o. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// blame: jnml, labs.nic.cz
+
+// +build ignore
+
+package main
+
+import (
+	"bytes"
+	"github.com/cznic/mathutil"
+	"image"
+	"image/png"
+	"io/ioutil"
+	"log"
+	"math"
+	"math/rand"
+)
+
+// $ go run example2.go # view rand.png and rnd.png by your favorite pic viewer
+//
+// see http://www.boallen.com/random-numbers.html
+func main() {
+	sqr := image.Rect(0, 0, 511, 511)
+	r, err := mathutil.NewFC32(math.MinInt32, math.MaxInt32, true)
+	if err != nil {
+		log.Fatal("NewFC32", err)
+	}
+
+	img := image.NewGray(sqr)
+	for y := 0; y < 512; y++ {
+		for x := 0; x < 512; x++ {
+			if r.Next()&1 != 0 {
+				img.Set(x, y, image.White)
+			}
+		}
+	}
+	buf := bytes.NewBuffer(nil)
+	if err := png.Encode(buf, img); err != nil {
+		log.Fatal("Encode rnd.png ", err)
+	}
+
+	if err := ioutil.WriteFile("rnd.png", buf.Bytes(), 0666); err != nil {
+		log.Fatal("ioutil.WriteFile/rnd.png ", err)
+	}
+
+	r2 := rand.New(rand.NewSource(0))
+	img = image.NewGray(sqr)
+	for y := 0; y < 512; y++ {
+		for x := 0; x < 512; x++ {
+			if r2.Int()&1 != 0 {
+				img.Set(x, y, image.White)
+			}
+		}
+	}
+	buf = bytes.NewBuffer(nil)
+	if err := png.Encode(buf, img); err != nil {
+		log.Fatal("Encode rand.png ", err)
+	}
+
+	if err := ioutil.WriteFile("rand.png", buf.Bytes(), 0666); err != nil {
+		log.Fatal("ioutil.WriteFile/rand.png ", err)
+	}
+}