From 564248641b5a4b693d4ca28be5c20070bf3ab047 Mon Sep 17 00:00:00 2001
From: Hajime Hoshi <hajimehoshi@gmail.com>
Date: Sun, 14 Jun 2015 03:27:02 +0900
Subject: [PATCH] audio: Fix examples' performance issue

---
 example/audio/main.go | 15 +++++++--------
 example/piano/main.go | 15 +++++++--------
 2 files changed, 14 insertions(+), 16 deletions(-)

diff --git a/example/audio/main.go b/example/audio/main.go
index 523b361fc..971d03b14 100644
--- a/example/audio/main.go
+++ b/example/audio/main.go
@@ -15,8 +15,6 @@
 package main
 
 import (
-	"bytes"
-	"encoding/binary"
 	"fmt"
 	"log"
 	"math"
@@ -76,13 +74,14 @@ func toBytes(l, r []int16) []byte {
 	if len(l) != len(r) {
 		panic("len(l) must equal to len(r)")
 	}
-	b := &bytes.Buffer{}
-	for i := 0; i < len(l); i++ {
-		if err := binary.Write(b, binary.LittleEndian, []int16{l[i], r[i]}); err != nil {
-			panic(err)
-		}
+	b := make([]byte, len(l)*4)
+	for i, _ := range l {
+		b[4*i] = byte(l[i])
+		b[4*i+1] = byte(l[i] >> 8)
+		b[4*i+2] = byte(r[i])
+		b[4*i+3] = byte(r[i] >> 8)
 	}
-	return b.Bytes()
+	return b
 }
 
 func addNote() {
diff --git a/example/piano/main.go b/example/piano/main.go
index 5c3a8a8dc..1fce4dcf2 100644
--- a/example/piano/main.go
+++ b/example/piano/main.go
@@ -15,8 +15,6 @@
 package main
 
 import (
-	"bytes"
-	"encoding/binary"
 	"fmt"
 	"image/color"
 	"log"
@@ -60,13 +58,14 @@ func toBytes(l, r []int16) []byte {
 	if len(l) != len(r) {
 		panic("len(l) must equal to len(r)")
 	}
-	b := &bytes.Buffer{}
-	for i := 0; i < len(l); i++ {
-		if err := binary.Write(b, binary.LittleEndian, []int16{l[i], r[i]}); err != nil {
-			panic(err)
-		}
+	b := make([]byte, len(l)*4)
+	for i, _ := range l {
+		b[4*i] = byte(l[i])
+		b[4*i+1] = byte(l[i] >> 8)
+		b[4*i+2] = byte(r[i])
+		b[4*i+3] = byte(r[i] >> 8)
 	}
-	return b.Bytes()
+	return b
 }
 
 func addNote(freq float64, vol float64) {