From 49fc723e668a47e5b4b0411016b1b94599ad4c00 Mon Sep 17 00:00:00 2001
From: Song Minjae <alswo9628@gmail.com>
Date: Mon, 26 Sep 2016 14:50:15 +0900
Subject: [PATCH] antialiased squarewave generator

Former-commit-id: c7d69891460f8f04681c28e1d05421ec1a93379d
Former-commit-id: 5767a006dd9221f1839eec3b1b0223670262f8fd
---
 .../torvald/terrarum/StateTestingSandbox.kt   | 127 ++++++++++++++++--
 src/net/torvald/terrarum/Terrarum.kt          |   4 +-
 2 files changed, 117 insertions(+), 14 deletions(-)

diff --git a/src/net/torvald/terrarum/StateTestingSandbox.kt b/src/net/torvald/terrarum/StateTestingSandbox.kt
index b1102618d..114a86428 100644
--- a/src/net/torvald/terrarum/StateTestingSandbox.kt
+++ b/src/net/torvald/terrarum/StateTestingSandbox.kt
@@ -1,11 +1,24 @@
 package net.torvald.terrarum
 
 
+import com.jme3.math.FastMath
+import net.torvald.terrarum.gameactors.floorInt
+import net.torvald.terrarum.gameactors.roundInt
+import net.torvald.terrarum.virtualcomputer.terminal.ALException
 import org.apache.commons.csv.CSVRecord
+import org.lwjgl.BufferUtils
+import org.lwjgl.openal.AL
+import org.lwjgl.openal.AL10
 import org.newdawn.slick.GameContainer
 import org.newdawn.slick.Graphics
 import org.newdawn.slick.state.BasicGameState
 import org.newdawn.slick.state.StateBasedGame
+import java.io.ByteArrayInputStream
+import java.nio.ByteBuffer
+import java.util.*
+import javax.sound.sampled.AudioFormat
+import javax.sound.sampled.AudioInputStream
+import javax.sound.sampled.AudioSystem
 
 /**
  * Created by minjaesong on 16-09-05.
@@ -13,28 +26,118 @@ import org.newdawn.slick.state.StateBasedGame
 class StateTestingSandbox : BasicGameState() {
 
 
-
     override fun init(container: GameContainer?, game: StateBasedGame?) {
+        playTone()
+    }
 
+    private val sampleRate = 22050
+    private var beepSource: Int? = null
+    private var beepBuffer: Int? = null
+
+    /**
+     * @param duration : milliseconds
+     */
+    private fun makeAudioData(duration: Int, freq: Float): ByteBuffer {
+        val audioData = BufferUtils.createByteBuffer(duration.times(sampleRate).div(1000))
+
+        val realDuration = duration * sampleRate / 1000
+        val chopSize = freq * 2f / sampleRate
+
+        val amp = Math.max(4600f / freq, 1f)
+        val nHarmonics = 4
+
+        val transitionThre = 1150f
+
+        if (freq < transitionThre) { // chopper generator (for low freq)
+            for (x in 0..realDuration - 1) {
+                var sine: Float = amp * FastMath.cos(FastMath.PI * x * chopSize)
+                if (sine > 1f) sine = 1f
+                else if (sine < -1f) sine = -1f
+                audioData.put(
+                        (0.5f + 0.5f * sine).times(0xFF).toByte()
+                )
+            }
+        }
+        else { // harmonics generator (for high freq)
+            for (x in 0..realDuration - 1) {
+                var sine: Float = 0f
+                for (k in 0..nHarmonics) { // mix only odd harmonics to make squarewave
+                    sine += (1f / (2*k + 1)) *
+                            FastMath.sin((2*k + 1) * FastMath.PI * x * chopSize)
+                }
+                audioData.put(
+                        (0.5f + 0.5f * sine).times(0xFF).toByte()
+                )
+            }
+        }
+
+        audioData.rewind()
+
+        return audioData
+    }
+
+    var audioData: ByteBuffer? = null
+
+    private fun playTone() {
+        if (audioData == null) audioData = makeAudioData(5000, 27.5f)
+
+
+        if (!AL.isCreated()) AL.create()
+
+
+        // Clear error stack.
+        AL10.alGetError()
+
+        beepBuffer = AL10.alGenBuffers()
+        checkALError()
+
+        try {
+            AL10.alBufferData(beepBuffer!!, AL10.AL_FORMAT_MONO8, audioData, sampleRate)
+            checkALError()
+
+            beepSource = AL10.alGenSources()
+            checkALError()
+
+            try {
+                AL10.alSourceQueueBuffers(beepSource!!, beepBuffer!!)
+                checkALError()
+
+                AL10.alSource3f(beepSource!!, AL10.AL_POSITION, 0f, 0f, 1f)
+                AL10.alSourcef(beepSource!!, AL10.AL_REFERENCE_DISTANCE, 1f)
+                AL10.alSourcef(beepSource!!, AL10.AL_MAX_DISTANCE, 1f)
+                AL10.alSourcef(beepSource!!, AL10.AL_GAIN, 0.3f)
+                checkALError()
+
+                AL10.alSourcePlay(beepSource!!)
+                checkALError()
+
+            }
+            catch (e: ALException) {
+                AL10.alDeleteSources(beepSource!!)
+            }
+        }
+        catch (e: ALException) {
+            if (beepSource != null) AL10.alDeleteSources(beepSource!!)
+        }
     }
 
     override fun update(container: GameContainer?, game: StateBasedGame?, delta: Int) {
-        throw UnsupportedOperationException("not implemented") //To change body of created functions use File | Settings | File Templates.
+
     }
 
+    // Custom implementation of Util.checkALError() that uses our custom exception.
+    private fun checkALError() {
+        val errorCode = AL10.alGetError()
+        if (errorCode != AL10.AL_NO_ERROR) {
+            throw ALException(errorCode)
+        }
+    }
+
+
     override fun getID() = Terrarum.STATE_ID_TEST_SHIT
 
     override fun render(container: GameContainer?, game: StateBasedGame?, g: Graphics?) {
+
     }
 
-    private fun intVal(rec: CSVRecord, s: String): Int {
-        var ret = -1
-        try {
-            ret = Integer.decode(rec.get(s))!!
-        }
-        catch (e: NullPointerException) {
-        }
-
-        return ret
-    }
 }
\ No newline at end of file
diff --git a/src/net/torvald/terrarum/Terrarum.kt b/src/net/torvald/terrarum/Terrarum.kt
index 88dcd9242..662a5af96 100644
--- a/src/net/torvald/terrarum/Terrarum.kt
+++ b/src/net/torvald/terrarum/Terrarum.kt
@@ -100,8 +100,8 @@ constructor(gamename: String) : StateBasedGame(gamename) {
 
         gc.graphics.clear() // clean up any 'dust' in the buffer
 
-        addState(StateVTTest())
-        //addState(StateTestingSandbox())
+        //addState(StateVTTest())
+        addState(StateTestingSandbox())
         //addState(StateSplash())
         //addState(StateMonitorCheck())
         //addState(StateFontTester())