initial commit

master
Anton Lydike 2 years ago
commit fca2ca7dc1

170
.gitignore vendored

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# Created by https://www.toptal.com/developers/gitignore/api/kotlin,gradle,intellij
# Edit at https://www.toptal.com/developers/gitignore?templates=kotlin,gradle,intellij
### Intellij ###
# Covers JetBrains IDEs: IntelliJ, RubyMine, PhpStorm, AppCode, PyCharm, CLion, Android Studio, WebStorm and Rider
# Reference: https://intellij-support.jetbrains.com/hc/en-us/articles/206544839
# User-specific stuff
.idea/**/workspace.xml
.idea/**/tasks.xml
.idea/**/usage.statistics.xml
.idea/**/dictionaries
.idea/**/shelf
# AWS User-specific
.idea/**/aws.xml
# Generated files
.idea/**/contentModel.xml
# Sensitive or high-churn files
.idea/**/dataSources/
.idea/**/dataSources.ids
.idea/**/dataSources.local.xml
.idea/**/sqlDataSources.xml
.idea/**/dynamic.xml
.idea/**/uiDesigner.xml
.idea/**/dbnavigator.xml
# Gradle
.idea/**/gradle.xml
.idea/**/libraries
# Gradle and Maven with auto-import
# When using Gradle or Maven with auto-import, you should exclude module files,
# since they will be recreated, and may cause churn. Uncomment if using
# auto-import.
# .idea/artifacts
# .idea/compiler.xml
# .idea/jarRepositories.xml
# .idea/modules.xml
# .idea/*.iml
# .idea/modules
# *.iml
# *.ipr
# CMake
cmake-build-*/
# Mongo Explorer plugin
.idea/**/mongoSettings.xml
# File-based project format
*.iws
# IntelliJ
out/
# mpeltonen/sbt-idea plugin
.idea_modules/
# JIRA plugin
atlassian-ide-plugin.xml
# Cursive Clojure plugin
.idea/replstate.xml
# SonarLint plugin
.idea/sonarlint/
# Crashlytics plugin (for Android Studio and IntelliJ)
com_crashlytics_export_strings.xml
crashlytics.properties
crashlytics-build.properties
fabric.properties
# Editor-based Rest Client
.idea/httpRequests
# Android studio 3.1+ serialized cache file
.idea/caches/build_file_checksums.ser
### Intellij Patch ###
# Comment Reason: https://github.com/joeblau/gitignore.io/issues/186#issuecomment-215987721
# *.iml
# modules.xml
# .idea/misc.xml
# *.ipr
# Sonarlint plugin
# https://plugins.jetbrains.com/plugin/7973-sonarlint
.idea/**/sonarlint/
# SonarQube Plugin
# https://plugins.jetbrains.com/plugin/7238-sonarqube-community-plugin
.idea/**/sonarIssues.xml
# Markdown Navigator plugin
# https://plugins.jetbrains.com/plugin/7896-markdown-navigator-enhanced
.idea/**/markdown-navigator.xml
.idea/**/markdown-navigator-enh.xml
.idea/**/markdown-navigator/
# Cache file creation bug
# See https://youtrack.jetbrains.com/issue/JBR-2257
.idea/$CACHE_FILE$
# CodeStream plugin
# https://plugins.jetbrains.com/plugin/12206-codestream
.idea/codestream.xml
# Azure Toolkit for IntelliJ plugin
# https://plugins.jetbrains.com/plugin/8053-azure-toolkit-for-intellij
.idea/**/azureSettings.xml
### Kotlin ###
# Compiled class file
*.class
# Log file
*.log
# BlueJ files
*.ctxt
# Mobile Tools for Java (J2ME)
.mtj.tmp/
# Package Files #
*.jar
*.war
*.nar
*.ear
*.zip
*.tar.gz
*.rar
# virtual machine crash logs, see http://www.java.com/en/download/help/error_hotspot.xml
hs_err_pid*
replay_pid*
### Gradle ###
.gradle
**/build/
!src/**/build/
# Ignore Gradle GUI config
gradle-app.setting
# Avoid ignoring Gradle wrapper jar file (.jar files are usually ignored)
!gradle-wrapper.jar
# Avoid ignore Gradle wrappper properties
!gradle-wrapper.properties
# Cache of project
.gradletasknamecache
# Eclipse Gradle plugin generated files
# Eclipse Core
.project
# JDT-specific (Eclipse Java Development Tools)
.classpath
### Gradle Patch ###
# Java heap dump
*.hprof
# End of https://www.toptal.com/developers/gitignore/api/kotlin,gradle,intellij

8
.idea/.gitignore vendored

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# Default ignored files
/shelf/
/workspace.xml
# Editor-based HTTP Client requests
/httpRequests/
# Datasource local storage ignored files
/dataSources/
/dataSources.local.xml

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<?xml version="1.0" encoding="UTF-8"?>
<project version="4">
<component name="CompilerConfiguration">
<bytecodeTargetLevel target="11" />
</component>
</project>

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<?xml version="1.0" encoding="UTF-8"?>
<project version="4">
<component name="RemoteRepositoriesConfiguration">
<remote-repository>
<option name="id" value="central" />
<option name="name" value="Maven Central repository" />
<option name="url" value="https://repo1.maven.org/maven2" />
</remote-repository>
<remote-repository>
<option name="id" value="jboss.community" />
<option name="name" value="JBoss Community repository" />
<option name="url" value="https://repository.jboss.org/nexus/content/repositories/public/" />
</remote-repository>
<remote-repository>
<option name="id" value="MavenRepo" />
<option name="name" value="MavenRepo" />
<option name="url" value="https://repo.maven.apache.org/maven2/" />
</remote-repository>
</component>
</project>

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<?xml version="1.0" encoding="UTF-8"?>
<project version="4">
<component name="KotlinJpsPluginSettings">
<option name="version" value="1.7.10" />
</component>
</project>

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<?xml version="1.0" encoding="UTF-8"?>
<project version="4">
<component name="ExternalStorageConfigurationManager" enabled="true" />
<component name="FrameworkDetectionExcludesConfiguration">
<file type="web" url="file://$PROJECT_DIR$" />
</component>
<component name="ProjectRootManager" version="2" languageLevel="JDK_11" default="true" project-jdk-name="11" project-jdk-type="JavaSDK">
<output url="file://$PROJECT_DIR$/out" />
</component>
</project>

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<?xml version="1.0" encoding="UTF-8"?>
<project version="4">
<component name="VcsDirectoryMappings">
<mapping directory="$PROJECT_DIR$" vcs="Git" />
</component>
</project>

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import org.jetbrains.kotlin.gradle.tasks.KotlinCompile
plugins {
kotlin("jvm") version "1.7.10"
application
}
group = "org.example"
version = "1.0-SNAPSHOT"
repositories {
mavenCentral()
}
dependencies {
testImplementation(kotlin("test"))
}
tasks.test {
useJUnitPlatform()
}
tasks.withType<KotlinCompile> {
kotlinOptions.jvmTarget = "1.8"
}
application {
mainClass.set("MainKt")
}

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kotlin.code.style=official

Binary file not shown.

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distributionBase=GRADLE_USER_HOME
distributionPath=wrapper/dists
distributionUrl=https\://services.gradle.org/distributions/gradle-7.4.2-bin.zip
zipStoreBase=GRADLE_USER_HOME
zipStorePath=wrapper/dists

234
gradlew vendored

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#!/bin/sh
#
# Copyright © 2015-2021 the original 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
#
# https://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.
#
##############################################################################
#
# Gradle start up script for POSIX generated by Gradle.
#
# Important for running:
#
# (1) You need a POSIX-compliant shell to run this script. If your /bin/sh is
# noncompliant, but you have some other compliant shell such as ksh or
# bash, then to run this script, type that shell name before the whole
# command line, like:
#
# ksh Gradle
#
# Busybox and similar reduced shells will NOT work, because this script
# requires all of these POSIX shell features:
# * functions;
# * expansions «$var», «${var}», «${var:-default}», «${var+SET}»,
# «${var#prefix}», «${var%suffix}», and «$( cmd )»;
# * compound commands having a testable exit status, especially «case»;
# * various built-in commands including «command», «set», and «ulimit».
#
# Important for patching:
#
# (2) This script targets any POSIX shell, so it avoids extensions provided
# by Bash, Ksh, etc; in particular arrays are avoided.
#
# The "traditional" practice of packing multiple parameters into a
# space-separated string is a well documented source of bugs and security
# problems, so this is (mostly) avoided, by progressively accumulating
# options in "$@", and eventually passing that to Java.
#
# Where the inherited environment variables (DEFAULT_JVM_OPTS, JAVA_OPTS,
# and GRADLE_OPTS) rely on word-splitting, this is performed explicitly;
# see the in-line comments for details.
#
# There are tweaks for specific operating systems such as AIX, CygWin,
# Darwin, MinGW, and NonStop.
#
# (3) This script is generated from the Groovy template
# https://github.com/gradle/gradle/blob/master/subprojects/plugins/src/main/resources/org/gradle/api/internal/plugins/unixStartScript.txt
# within the Gradle project.
#
# You can find Gradle at https://github.com/gradle/gradle/.
#
##############################################################################
# Attempt to set APP_HOME
# Resolve links: $0 may be a link
app_path=$0
# Need this for daisy-chained symlinks.
while
APP_HOME=${app_path%"${app_path##*/}"} # leaves a trailing /; empty if no leading path
[ -h "$app_path" ]
do
ls=$( ls -ld "$app_path" )
link=${ls#*' -> '}
case $link in #(
/*) app_path=$link ;; #(
*) app_path=$APP_HOME$link ;;
esac
done
APP_HOME=$( cd "${APP_HOME:-./}" && pwd -P ) || exit
APP_NAME="Gradle"
APP_BASE_NAME=${0##*/}
# Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
DEFAULT_JVM_OPTS='"-Xmx64m" "-Xms64m"'
# Use the maximum available, or set MAX_FD != -1 to use that value.
MAX_FD=maximum
warn () {
echo "$*"
} >&2
die () {
echo
echo "$*"
echo
exit 1
} >&2
# OS specific support (must be 'true' or 'false').
cygwin=false
msys=false
darwin=false
nonstop=false
case "$( uname )" in #(
CYGWIN* ) cygwin=true ;; #(
Darwin* ) darwin=true ;; #(
MSYS* | MINGW* ) msys=true ;; #(
NONSTOP* ) nonstop=true ;;
esac
CLASSPATH=$APP_HOME/gradle/wrapper/gradle-wrapper.jar
# Determine the Java command to use to start the JVM.
if [ -n "$JAVA_HOME" ] ; then
if [ -x "$JAVA_HOME/jre/sh/java" ] ; then
# IBM's JDK on AIX uses strange locations for the executables
JAVACMD=$JAVA_HOME/jre/sh/java
else
JAVACMD=$JAVA_HOME/bin/java
fi
if [ ! -x "$JAVACMD" ] ; then
die "ERROR: JAVA_HOME is set to an invalid directory: $JAVA_HOME
Please set the JAVA_HOME variable in your environment to match the
location of your Java installation."
fi
else
JAVACMD=java
which java >/dev/null 2>&1 || die "ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
Please set the JAVA_HOME variable in your environment to match the
location of your Java installation."
fi
# Increase the maximum file descriptors if we can.
if ! "$cygwin" && ! "$darwin" && ! "$nonstop" ; then
case $MAX_FD in #(
max*)
MAX_FD=$( ulimit -H -n ) ||
warn "Could not query maximum file descriptor limit"
esac
case $MAX_FD in #(
'' | soft) :;; #(
*)
ulimit -n "$MAX_FD" ||
warn "Could not set maximum file descriptor limit to $MAX_FD"
esac
fi
# Collect all arguments for the java command, stacking in reverse order:
# * args from the command line
# * the main class name
# * -classpath
# * -D...appname settings
# * --module-path (only if needed)
# * DEFAULT_JVM_OPTS, JAVA_OPTS, and GRADLE_OPTS environment variables.
# For Cygwin or MSYS, switch paths to Windows format before running java
if "$cygwin" || "$msys" ; then
APP_HOME=$( cygpath --path --mixed "$APP_HOME" )
CLASSPATH=$( cygpath --path --mixed "$CLASSPATH" )
JAVACMD=$( cygpath --unix "$JAVACMD" )
# Now convert the arguments - kludge to limit ourselves to /bin/sh
for arg do
if
case $arg in #(
-*) false ;; # don't mess with options #(
/?*) t=${arg#/} t=/${t%%/*} # looks like a POSIX filepath
[ -e "$t" ] ;; #(
*) false ;;
esac
then
arg=$( cygpath --path --ignore --mixed "$arg" )
fi
# Roll the args list around exactly as many times as the number of
# args, so each arg winds up back in the position where it started, but
# possibly modified.
#
# NB: a `for` loop captures its iteration list before it begins, so
# changing the positional parameters here affects neither the number of
# iterations, nor the values presented in `arg`.
shift # remove old arg
set -- "$@" "$arg" # push replacement arg
done
fi
# Collect all arguments for the java command;
# * $DEFAULT_JVM_OPTS, $JAVA_OPTS, and $GRADLE_OPTS can contain fragments of
# shell script including quotes and variable substitutions, so put them in
# double quotes to make sure that they get re-expanded; and
# * put everything else in single quotes, so that it's not re-expanded.
set -- \
"-Dorg.gradle.appname=$APP_BASE_NAME" \
-classpath "$CLASSPATH" \
org.gradle.wrapper.GradleWrapperMain \
"$@"
# Use "xargs" to parse quoted args.
#
# With -n1 it outputs one arg per line, with the quotes and backslashes removed.
#
# In Bash we could simply go:
#
# readarray ARGS < <( xargs -n1 <<<"$var" ) &&
# set -- "${ARGS[@]}" "$@"
#
# but POSIX shell has neither arrays nor command substitution, so instead we
# post-process each arg (as a line of input to sed) to backslash-escape any
# character that might be a shell metacharacter, then use eval to reverse
# that process (while maintaining the separation between arguments), and wrap
# the whole thing up as a single "set" statement.
#
# This will of course break if any of these variables contains a newline or
# an unmatched quote.
#
eval "set -- $(
printf '%s\n' "$DEFAULT_JVM_OPTS $JAVA_OPTS $GRADLE_OPTS" |
xargs -n1 |
sed ' s~[^-[:alnum:]+,./:=@_]~\\&~g; ' |
tr '\n' ' '
)" '"$@"'
exec "$JAVACMD" "$@"

89
gradlew.bat vendored

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@rem
@rem Copyright 2015 the original author or authors.
@rem
@rem Licensed under the Apache License, Version 2.0 (the "License");
@rem you may not use this file except in compliance with the License.
@rem You may obtain a copy of the License at
@rem
@rem https://www.apache.org/licenses/LICENSE-2.0
@rem
@rem Unless required by applicable law or agreed to in writing, software
@rem distributed under the License is distributed on an "AS IS" BASIS,
@rem WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
@rem See the License for the specific language governing permissions and
@rem limitations under the License.
@rem
@if "%DEBUG%" == "" @echo off
@rem ##########################################################################
@rem
@rem Gradle startup script for Windows
@rem
@rem ##########################################################################
@rem Set local scope for the variables with windows NT shell
if "%OS%"=="Windows_NT" setlocal
set DIRNAME=%~dp0
if "%DIRNAME%" == "" set DIRNAME=.
set APP_BASE_NAME=%~n0
set APP_HOME=%DIRNAME%
@rem Resolve any "." and ".." in APP_HOME to make it shorter.
for %%i in ("%APP_HOME%") do set APP_HOME=%%~fi
@rem Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
set DEFAULT_JVM_OPTS="-Xmx64m" "-Xms64m"
@rem Find java.exe
if defined JAVA_HOME goto findJavaFromJavaHome
set JAVA_EXE=java.exe
%JAVA_EXE% -version >NUL 2>&1
if "%ERRORLEVEL%" == "0" goto execute
echo.
echo ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
echo.
echo Please set the JAVA_HOME variable in your environment to match the
echo location of your Java installation.
goto fail
:findJavaFromJavaHome
set JAVA_HOME=%JAVA_HOME:"=%
set JAVA_EXE=%JAVA_HOME%/bin/java.exe
if exist "%JAVA_EXE%" goto execute
echo.
echo ERROR: JAVA_HOME is set to an invalid directory: %JAVA_HOME%
echo.
echo Please set the JAVA_HOME variable in your environment to match the
echo location of your Java installation.
goto fail
:execute
@rem Setup the command line
set CLASSPATH=%APP_HOME%\gradle\wrapper\gradle-wrapper.jar
@rem Execute Gradle
"%JAVA_EXE%" %DEFAULT_JVM_OPTS% %JAVA_OPTS% %GRADLE_OPTS% "-Dorg.gradle.appname=%APP_BASE_NAME%" -classpath "%CLASSPATH%" org.gradle.wrapper.GradleWrapperMain %*
:end
@rem End local scope for the variables with windows NT shell
if "%ERRORLEVEL%"=="0" goto mainEnd
:fail
rem Set variable GRADLE_EXIT_CONSOLE if you need the _script_ return code instead of
rem the _cmd.exe /c_ return code!
if not "" == "%GRADLE_EXIT_CONSOLE%" exit 1
exit /b 1
:mainEnd
if "%OS%"=="Windows_NT" endlocal
:omega

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rootProject.name = "procedural-musix"

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import java.util.concurrent.BlockingQueue
import java.util.concurrent.LinkedBlockingQueue
import javax.sound.sampled.AudioFormat
import javax.sound.sampled.AudioSystem
import javax.sound.sampled.DataLine
import javax.sound.sampled.SourceDataLine
class AudioChunk(val tick: Int, val samples: SoundSamples) {
fun toBytes(): ByteArray = ByteArray(samples.size * 2) {
i -> ((samples[i/2] * Params.MAX_VAL).toInt() shr ((i % 2) * 8)).toByte()
}
}
class AudioSink : Thread() {
private val chunks: BlockingQueue<ByteArray> = LinkedBlockingQueue();
val queueSize: Int
get() = chunks.size
fun enqueueChunk(chunk: AudioChunk) {
chunks.add(chunk.toBytes())
}
var running : Boolean = false
private set
override fun run() {
val format = AudioFormat(Params.SAMPLES, 16, 1, true, false)
val info = DataLine.Info(SourceDataLine::class.java, format)
val line = AudioSystem.getLine(info) as SourceDataLine
line.open(format)
line.start()
while (true) {
if (chunks.isEmpty()) {
if (!running)
break
System.err.println("Empty chunks queue! Work faster!")
}
val next = chunks.take()
line.write(next, 0, next.size)
}
line.close()
}
fun terminate(empty_queue: Boolean = false) {
if (empty_queue) {
chunks.clear()
}
running = false
join()
}
override fun start() {
running = true
super.start()
}
}

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import Params.PI
import Params.TWO_PI
import Params.as_samples
import filter.Compressor
import filter.Limiter
import kotlin.math.cos
import kotlin.math.pow
import kotlin.math.sin
object Params {
const val SAMPLES = 44100f
const val PI = kotlin.math.PI.toFloat()
const val TWO_PI = 2f * kotlin.math.PI.toFloat()
val MAX_VAL = (2.toDouble().pow(15)-1).toInt()
val CORES = Runtime.getRuntime().availableProcessors()
fun as_samples(seconds: Float): Float = SAMPLES * seconds
}
private const val F0: Float = 440f;
fun toFrequency(tone: Float): Float = F0 * 2f.pow(tone / 12f)
abstract class StepGenerator {
abstract fun generateSingle(time: Float): Float
open fun generate(time: TimeSignal): SoundSamples = SoundSamples(time.size) { i -> generateSingle(time[i]) }
}
class SineWaveGenerator(var tone: Float) : StepGenerator() {
override fun generateSingle(time: Float): Float {
return sin(time * toFrequency(tone) * TWO_PI)
}
}
fun main(args: Array<String>) {
val sink = AudioSink()
val gen = SoundMachine()
gen.globalEffects.add(Compressor(as_samples(.4f).toInt())::apply)
gen.globalEffects.add(Limiter(.9f)::apply)
gen.generators.add(Chain(SineWaveGenerator(0f)::generate, ArrayList()))
sink.enqueueChunk(gen.nextChunk())
sink.start()
for (i in 1..100) {
sink.enqueueChunk(gen.nextChunk())
}
sink.terminate()
}

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import SoundMachine.State.last_time
typealias TimeSignal = FloatArray
typealias SoundSamples = FloatArray
// SoundSamples represent samples from a wave, sampled Params.SAMPLES times per second.
typealias Generator = (TimeSignal) -> SoundSamples
typealias Effect = (SoundSamples) -> SoundSamples
class Chain(
val generator: Generator,
val effects: List<Effect>
) {
fun apply(signal: TimeSignal): SoundSamples = effects.fold(generator(signal)) { acc, effect -> effect(acc) }
}
fun SoundSamples.combine(sample: SoundSamples) : SoundSamples{
return SoundSamples(sample.size) { i -> this[i] + sample[i]}
}
class SoundMachine() {
object State {
var tick : Int = 0
// the current tick we're on. One tick = one beat
var bpm : Float = 64f
var last_time: Float = 0f
// the current speed (bpm)
}
val generators : MutableList<Chain> = ArrayList()
val globalEffects: MutableList<Effect> = ArrayList()
fun nextChunk() : AudioChunk {
// let's generate the next beat!
// grab current tick
val tick = State.tick++
// compute samples per beat (since bpm is variable, recompute every beat)
// TODO optimization opportunity
val secondsPerBeat = 60 / State.bpm
val samplesPerBeat = secondsPerBeat * Params.SAMPLES;
val base : TimeSignal = TimeSignal(samplesPerBeat.toInt()) { i -> (i / Params.SAMPLES) + last_time }
last_time += secondsPerBeat
val result = generators.map { gen -> gen.apply(base) } .reduce { acc, sample -> acc.combine(sample) }
return AudioChunk(
tick,
globalEffects.fold(result) { acc, effect -> effect(acc) }
)
}
}

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package filter
import java.lang.Float.max
import java.lang.Float.min
import java.util.*
fun clamp(min_val: Float, value: Float, max_val: Float) : Float{
return max(min(value, max_val), min_val)
}
class EchoFilter(size: Int, private val volume: Float = 0.5f) : StepFilter() {
private val cache: Queue<Float> = LinkedList(List(size) { 0f })
override fun step(value: Float): Float {
val effect = value + cache.remove() * volume
cache.add(effect)
return effect
}
}
class Limiter(private val limit_to: Float): StepFilter() {
override fun step(value: Float): Float = clamp(-limit_to, value, limit_to)
}

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package filter
import SoundSamples
import java.lang.Float.max
abstract class StepFilter {
abstract fun step(value: Float): Float
open fun apply(samples: SoundSamples): SoundSamples = SoundSamples(samples.size) { i -> step(samples[i])}
}
class FloatRingBuffer(val size: Int, default: Float = 0f) {
val array = FloatArray(size) {default}
var pos = 0
fun push(value: Float): Float {
val next_pos = pos++ % size
val old_val = array[next_pos]
array[next_pos] = value
return old_val
}
}
class Compressor(size: Int): StepFilter() {
val buff = FloatRingBuffer(size, 1f)
var max_val : Float = 1f
override fun step(value: Float): Float {
val old = buff.push(value)
max_val = max(value, max(old, max_val))
return value / max_val
}
}

@ -0,0 +1,107 @@
package random;
import java.util.Random;
public class RandomDisplacementFractal {
/** Source of entropy */
private Random rand_;
/** Amount of roughness */
float roughness_;
/** Plasma fractal grid */
private float[][] grid_;
/** Generate a noise source based upon the midpoint displacement fractal.
*
* @param rand The random number generator
* @param roughness a roughness parameter
* @param width the width of the grid
* @param height the height of the grid
*/
public RandomDisplacementFractal(Random rand, float roughness, int width, int height) {
roughness_ = roughness / width;
grid_ = new float[width][height];
rand_ = (rand == null) ? new Random() : rand;
}
public void initialise() {
int xh = grid_.length - 1;
int yh = grid_[0].length - 1;
// set the corner points
grid_[0][0] = rand_.nextFloat() - 0.5f;
grid_[0][yh] = rand_.nextFloat() - 0.5f;
grid_[xh][0] = rand_.nextFloat() - 0.5f;
grid_[xh][yh] = rand_.nextFloat() - 0.5f;
// generate the fractal
generate(0, 0, xh, yh);
}
// Add a suitable amount of random displacement to a point
private float roughen(float v, int l, int h) {
return v + roughness_ * (float) (rand_.nextGaussian() * (h - l));
}
// generate the fractal
private void generate(int xl, int yl, int xh, int yh) {
int xm = (xl + xh) / 2;
int ym = (yl + yh) / 2;
if ((xl == xm) && (yl == ym)) return;
grid_[xm][yl] = 0.5f * (grid_[xl][yl] + grid_[xh][yl]);
grid_[xm][yh] = 0.5f * (grid_[xl][yh] + grid_[xh][yh]);
grid_[xl][ym] = 0.5f * (grid_[xl][yl] + grid_[xl][yh]);
grid_[xh][ym] = 0.5f * (grid_[xh][yl] + grid_[xh][yh]);
float v = roughen(0.5f * (grid_[xm][yl] + grid_[xm][yh]), xl + yl, yh
+ xh);
grid_[xm][ym] = v;
grid_[xm][yl] = roughen(grid_[xm][yl], xl, xh);
grid_[xm][yh] = roughen(grid_[xm][yh], xl, xh);
grid_[xl][ym] = roughen(grid_[xl][ym], yl, yh);
grid_[xh][ym] = roughen(grid_[xh][ym], yl, yh);
generate(xl, yl, xm, ym);
generate(xm, yl, xh, ym);
generate(xl, ym, xm, yh);
generate(xm, ym, xh, yh);
}
/**
* Dump out as a CSV
*/
public void printAsCSV() {
for(int i = 0;i < grid_.length;i++) {
for(int j = 0;j < grid_[0].length;j++) {
System.out.print(grid_[i][j]);
System.out.print(",");
}
System.out.println();
}
}
/**
* Convert to a Boolean array
* @return the boolean array
*/
public boolean[][] toBooleans() {
int w = grid_.length;
int h = grid_[0].length;
boolean[][] ret = new boolean[w][h];
for(int i = 0;i < w;i++) {
for(int j = 0;j < h;j++) {
ret[i][j] = grid_[i][j] < 0;
}
}
return ret;
}
}
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