diff --git a/.gitignore b/.gitignore
index 2100949..337e3a2 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,4 +1,27 @@
-.idea/
-*.tga
+.gradle
+build/
+!gradle/wrapper/gradle-wrapper.jar
+!**/src/main/**/build/
+!**/src/test/**/build/
+
+### IntelliJ IDEA ###
+.idea/modules.xml
+.idea/jarRepositories.xml
+.idea/compiler.xml
+.idea/libraries/
+*.iws
*.iml
+*.ipr
out/
+!**/src/main/**/out/
+!**/src/test/**/out/
+
+### Kotlin ###
+.kotlin
+
+
+### Mac OS ###
+.DS_Store
+
+
+test.tga
diff --git a/.idea/.gitignore b/.idea/.gitignore
new file mode 100644
index 0000000..26d3352
--- /dev/null
+++ b/.idea/.gitignore
@@ -0,0 +1,3 @@
+# Default ignored files
+/shelf/
+/workspace.xml
diff --git a/.idea/.name b/.idea/.name
new file mode 100644
index 0000000..c5d0eb8
--- /dev/null
+++ b/.idea/.name
@@ -0,0 +1 @@
+Ray
\ No newline at end of file
diff --git a/.idea/codeStyles/Project.xml b/.idea/codeStyles/Project.xml
new file mode 100644
index 0000000..1bec35e
--- /dev/null
+++ b/.idea/codeStyles/Project.xml
@@ -0,0 +1,10 @@
+
+
+
+
+
+
+
+
+
+
\ No newline at end of file
diff --git a/.idea/codeStyles/codeStyleConfig.xml b/.idea/codeStyles/codeStyleConfig.xml
new file mode 100644
index 0000000..79ee123
--- /dev/null
+++ b/.idea/codeStyles/codeStyleConfig.xml
@@ -0,0 +1,5 @@
+
+
+
+
+
\ No newline at end of file
diff --git a/.idea/gradle.xml b/.idea/gradle.xml
new file mode 100644
index 0000000..f2c1963
--- /dev/null
+++ b/.idea/gradle.xml
@@ -0,0 +1,17 @@
+
+
+
+
+
+
+
\ No newline at end of file
diff --git a/.idea/kotlinc.xml b/.idea/kotlinc.xml
new file mode 100644
index 0000000..c224ad5
--- /dev/null
+++ b/.idea/kotlinc.xml
@@ -0,0 +1,6 @@
+
+
+
+
+
+
\ No newline at end of file
diff --git a/.idea/misc.xml b/.idea/misc.xml
new file mode 100644
index 0000000..82e74d9
--- /dev/null
+++ b/.idea/misc.xml
@@ -0,0 +1,7 @@
+
+
+
+
+
+
+
\ No newline at end of file
diff --git a/.idea/vcs.xml b/.idea/vcs.xml
new file mode 100644
index 0000000..35eb1dd
--- /dev/null
+++ b/.idea/vcs.xml
@@ -0,0 +1,6 @@
+
+
+
+
+
+
\ No newline at end of file
diff --git a/build.gradle.kts b/build.gradle.kts
new file mode 100644
index 0000000..0aea81a
--- /dev/null
+++ b/build.gradle.kts
@@ -0,0 +1,18 @@
+plugins {
+ kotlin("jvm") version "2.0.21"
+}
+
+group = "org.example"
+version = "1.0-SNAPSHOT"
+
+repositories {
+ mavenCentral()
+}
+
+dependencies {
+ testImplementation(kotlin("test"))
+}
+
+tasks.test {
+ useJUnitPlatform()
+}
diff --git a/gradle.properties b/gradle.properties
new file mode 100644
index 0000000..7fc6f1f
--- /dev/null
+++ b/gradle.properties
@@ -0,0 +1 @@
+kotlin.code.style=official
diff --git a/gradle/wrapper/gradle-wrapper.jar b/gradle/wrapper/gradle-wrapper.jar
new file mode 100644
index 0000000..249e583
Binary files /dev/null and b/gradle/wrapper/gradle-wrapper.jar differ
diff --git a/gradle/wrapper/gradle-wrapper.properties b/gradle/wrapper/gradle-wrapper.properties
new file mode 100644
index 0000000..ce18f94
--- /dev/null
+++ b/gradle/wrapper/gradle-wrapper.properties
@@ -0,0 +1,6 @@
+#Wed Nov 20 18:10:35 CET 2024
+distributionBase=GRADLE_USER_HOME
+distributionPath=wrapper/dists
+distributionUrl=https\://services.gradle.org/distributions/gradle-8.10-bin.zip
+zipStoreBase=GRADLE_USER_HOME
+zipStorePath=wrapper/dists
diff --git a/gradlew b/gradlew
new file mode 100644
index 0000000..1b6c787
--- /dev/null
+++ b/gradlew
@@ -0,0 +1,234 @@
+#!/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 "$JAVACMD" "$@"
diff --git a/gradlew.bat b/gradlew.bat
new file mode 100644
index 0000000..107acd3
--- /dev/null
+++ b/gradlew.bat
@@ -0,0 +1,89 @@
+@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
diff --git a/settings.gradle.kts b/settings.gradle.kts
new file mode 100644
index 0000000..5e83f19
--- /dev/null
+++ b/settings.gradle.kts
@@ -0,0 +1,2 @@
+rootProject.name = "Ray"
+
diff --git a/src/Ray.kt b/src/Ray.kt
deleted file mode 100644
index 6ca7ffc..0000000
--- a/src/Ray.kt
+++ /dev/null
@@ -1,130 +0,0 @@
-import java.io.File
-import java.lang.Float.max
-import kotlin.math.min
-import kotlin.math.pow
-import kotlin.math.sqrt
-
-data class Hit(val point: Point, val normal: Vector, val distance: Float, val color: MaterialColor)
-
-data class MaterialColor(val r: Float, val g: Float, val b: Float) {
- fun toColor(): Color = Color(
- (r * UByte.MAX_VALUE.toFloat()).toInt().toUByte(),
- (g * UByte.MAX_VALUE.toFloat()).toInt().toUByte(),
- (b * UByte.MAX_VALUE.toFloat()).toInt().toUByte()
- )
-
- operator fun times(rhs: MaterialColor) = MaterialColor(r * rhs.r, g * rhs.g, b * rhs.b)
- operator fun plus(rhs: MaterialColor) = MaterialColor(r + rhs.r, g + rhs.g, b + rhs.b)
-}
-
-operator fun Float.times(rhs: MaterialColor) = MaterialColor(this * rhs.r, this * rhs.g, this * rhs.b)
-
-data class Ray(val origin: Point, val direction: Vector) {
- fun at(t: Float) = origin + t * direction
-}
-
-interface Thing {
- fun intersects(ray: Ray): Hit?
-}
-
-
-data class Plane(val point: Point, val normal: Vector, val color: MaterialColor) : Thing {
- override fun intersects(ray: Ray): Hit? {
- val bottom = dot(normal, ray.direction)
- if (bottom == 0.0f) return null
- val t = dot(normal, point - ray.origin) / bottom
- if (t <= 0.0f) return null
- return Hit(ray.at(t), normal, t, color)
- }
-}
-
-data class Sphere(val center: Point, val radius: Float, val color: MaterialColor) : Thing {
- override fun intersects(ray: Ray): Hit? {
- val l = center - ray.origin
- val tc = dot(l, ray.direction)
- if (tc < 0f) return null
-
- val d = l.squaredLength - tc * tc
- val radiusSquared = radius * radius
-
- if (d > radiusSquared) return null
-
- val thc = sqrt(radiusSquared - d)
-
- val t = min(tc - thc, tc + thc)
-
- val hitPoint = ray.at(t)
- return Hit(hitPoint, (hitPoint - center).normalized(), t, color)
- }
-}
-
-fun dot(lhs: Vector, rhs: Vector): Float = lhs.x * rhs.x + lhs.y * rhs.y + lhs.z * rhs.z
-
-data class PointLight(val point: Point, val color: MaterialColor)
-
-data class Scene(val things: List): Thing {
- override fun intersects(ray: Ray): Hit? {
- var closest: Hit? = null
- for (thing in things) {
- val hit = thing.intersects(ray)
- if (hit != null && (closest == null || hit.distance < closest.distance)) {
- closest = hit
- }
- }
-
- return closest
- }
-}
-
-fun main() {
- val bmp = Bitmap(1000, 1000)
- val origin = Point(500f, 500f, -500f)
-
- val sphere = Sphere(Point(500f, 500f, 500f), radius = 500f, color = MaterialColor(0f, 1.0f, 0f))
- val plane = Plane(
- Point(0f, -1000f, 0f),
- normal = Vector(0f, 1f, 0f),
- color = MaterialColor(0.5f, 0.5f, 0.5f)
- )
-
- val leftPlane = Plane(
- Point(-1000f, 0f, 0f),
- Vector(1f, 0f, 0f),
- color = MaterialColor(0.9f, 0.9f, 0.5f)
- )
-
- val scene = Scene(listOf(sphere, plane, leftPlane))
-
- val ambient = MaterialColor(0.1f, 0.1f, 0.1f)
-
- val light = PointLight(Point(1000f, 1000f, -500f), color = MaterialColor(0.5f, 0.5f, 0.5f))
- val specular = 100f
-
- for (y in 0 until bmp.height) {
- for (x in 0 until bmp.width) {
- val point = Point(x.toFloat(), y.toFloat(), 0f)
- val ray = origin.rayTo(point)
-
- val hit = scene.intersects(ray)
- if (hit != null) {
- var color = hit.color * ambient
-
- val rayToLight = (hit.point + 0.0001f * hit.normal).rayTo(light.point)
- if (scene.intersects(rayToLight) == null) {
-
- val lambert = max(0f, dot(hit.normal, rayToLight.direction))
- color += lambert * light.color
-
- val h = (-ray.direction + rayToLight.direction).normalized()
-
- val intensity = dot(hit.normal, h).pow(specular)
-
- color += intensity * MaterialColor(0.3f, 0f, 0f)
- }
-
- bmp.setPixel(x, y, color.toColor())
- }
- }
- }
- File("test.tga").writeBitmap(bmp)
-}
diff --git a/src/Bitmap.kt b/src/main/kotlin/Bitmap.kt
similarity index 100%
rename from src/Bitmap.kt
rename to src/main/kotlin/Bitmap.kt
diff --git a/src/Point.kt b/src/main/kotlin/Point.kt
similarity index 100%
rename from src/Point.kt
rename to src/main/kotlin/Point.kt
diff --git a/src/main/kotlin/Ray.kt b/src/main/kotlin/Ray.kt
new file mode 100644
index 0000000..ff45f50
--- /dev/null
+++ b/src/main/kotlin/Ray.kt
@@ -0,0 +1,190 @@
+import java.io.File
+import java.lang.Float.max
+import kotlin.math.min
+import kotlin.math.pow
+import kotlin.math.sqrt
+
+data class Hit(val point: Point, val normal: Vector, val distance: Float, val material: Material)
+
+data class MaterialColor(val r: Float, val g: Float, val b: Float) {
+ fun toColor(): Color = Color(
+ (r * UByte.MAX_VALUE.toFloat()).toInt().toUByte(),
+ (g * UByte.MAX_VALUE.toFloat()).toInt().toUByte(),
+ (b * UByte.MAX_VALUE.toFloat()).toInt().toUByte()
+ )
+
+ operator fun times(rhs: MaterialColor) = MaterialColor(r * rhs.r, g * rhs.g, b * rhs.b)
+ operator fun plus(rhs: MaterialColor) = MaterialColor(r + rhs.r, g + rhs.g, b + rhs.b)
+
+ companion object {
+ val Black: MaterialColor = MaterialColor(0f, 0f, 0f)
+ }
+}
+
+operator fun Float.times(rhs: MaterialColor) = MaterialColor(this * rhs.r, this * rhs.g, this * rhs.b)
+
+data class Ray(val origin: Point, val direction: Vector) {
+ fun at(t: Float) = origin + t * direction
+}
+
+interface Thing {
+ fun intersects(ray: Ray): Hit?
+}
+
+interface Material {
+ fun shade(ray: Ray, hit: Hit, scene: Scene): MaterialColor
+}
+
+data class WhateverMaterial(val color: MaterialColor,
+ val ambient: MaterialColor = MaterialColor(0.1f, 0.1f, 0.1f),
+ val specular: Float = 100f
+): Material {
+ override fun shade(ray: Ray, hit: Hit, scene: Scene): MaterialColor {
+ var color = this.color * ambient
+ val light = scene.light
+ val rayToLight = (hit.point + 0.0001f * hit.normal).rayTo(light.point)
+ if (scene.intersects(rayToLight) == null) {
+
+ val lambert = max(0f, dot(hit.normal, rayToLight.direction))
+ color += lambert * light.color
+
+ val h = (-ray.direction + rayToLight.direction).normalized()
+
+ val intensity = dot(hit.normal, h).pow(specular)
+
+ color += intensity * MaterialColor(0.3f, 0f, 0f)
+ }
+
+ return color
+ }
+}
+
+data class ReflectiveMaterial(
+ val reflectivity: Float,
+ val color: MaterialColor,
+ val ambient: MaterialColor = MaterialColor(0.1f, 0.1f, 0.1f),
+ val specular: Float = 10f
+): Material {
+ override fun shade(ray: Ray, hit: Hit, scene: Scene): MaterialColor {
+ var color = this.color * ambient
+ val light = scene.light
+ val offsetPoint = hit.point + 0.0001f * hit.normal
+ val rayToLight = offsetPoint.rayTo(light.point)
+ if (scene.intersects(rayToLight) == null) {
+
+ val lambert = max(0f, dot(hit.normal, rayToLight.direction))
+ color += lambert * light.color
+
+ val h = (-ray.direction + rayToLight.direction).normalized()
+
+ val intensity = (hit.normal dot h).pow(specular)
+
+ color += intensity * MaterialColor(0.3f, 0f, 0f)
+ }
+
+ val reflectionDirection = ray.direction - 2 * (ray.direction dot hit.normal) * hit.normal
+ val reflectedColor = scene.colorForRay(Ray(offsetPoint, reflectionDirection)) ?: MaterialColor.Black
+
+ return (1.0f - reflectivity) * color + reflectivity * reflectedColor
+ }
+}
+
+
+data class Plane(val point: Point, val normal: Vector, val material: Material) : Thing {
+ override fun intersects(ray: Ray): Hit? {
+ val bottom = dot(normal, ray.direction)
+ if (bottom == 0.0f) return null
+ val t = dot(normal, point - ray.origin) / bottom
+ if (t <= 0.0f) return null
+ return Hit(ray.at(t), normal, t, material)
+ }
+}
+
+data class Sphere(val center: Point, val radius: Float, val material: Material) : Thing {
+ override fun intersects(ray: Ray): Hit? {
+ val l = center - ray.origin
+ val tc = dot(l, ray.direction)
+ if (tc < 0f) return null
+
+ val d = l.squaredLength - tc * tc
+ val radiusSquared = radius * radius
+
+ if (d > radiusSquared) return null
+
+ val thc = sqrt(radiusSquared - d)
+
+ val t = min(tc - thc, tc + thc)
+
+ val hitPoint = ray.at(t)
+ return Hit(hitPoint, (hitPoint - center).normalized(), t, material)
+ }
+}
+
+fun dot(lhs: Vector, rhs: Vector): Float = lhs.x * rhs.x + lhs.y * rhs.y + lhs.z * rhs.z
+
+data class PointLight(val point: Point, val color: MaterialColor)
+
+data class Scene(val things: List, val light: PointLight): Thing {
+ override fun intersects(ray: Ray): Hit? {
+ var closest: Hit? = null
+ for (thing in things) {
+ val hit = thing.intersects(ray)
+ if (hit != null && (closest == null || hit.distance < closest.distance)) {
+ closest = hit
+ }
+ }
+
+ return closest
+ }
+
+ fun colorForRay(ray: Ray): MaterialColor? {
+ val hit = intersects(ray)
+ if (hit != null) {
+ return hit.material.shade(ray, hit, this)
+ }
+ return null
+ }
+}
+
+fun main() {
+ val bmp = Bitmap(1000, 1000)
+ val origin = Point(500f, 500f, -500f)
+
+ val sphere = Sphere(Point(500f, 500f, 500f), radius = 500f, material = ReflectiveMaterial(reflectivity = 0.2f, MaterialColor(0f, 1.0f, 0f)))
+ val sphere2 = Sphere(Point(0f, 500f, 50f), radius = 50f, material = ReflectiveMaterial(reflectivity = 0.2f, MaterialColor(1.0f, 0.0f, 0.1f)))
+
+ val plane = Plane(
+ Point(0f, -1000f, 0f),
+ normal = Vector(0f, 1f, 0f),
+ material = WhateverMaterial(MaterialColor(1f, 0.0f, 0.0f))
+ )
+
+ val leftPlane = Plane(
+ Point(-1000f, 0f, 0f),
+ Vector(1f, 0f, 0f),
+ material = WhateverMaterial(MaterialColor(0.0f, 1f, 0.0f))
+ )
+
+ val light = PointLight(Point(1000f, 1000f, -500f), color = 0.2f * MaterialColor(0.9f, 0.9f, 0.9f))
+
+ val scene = Scene(listOf(
+ sphere,
+ sphere2,
+ plane,
+ leftPlane
+ ), light = light)
+
+
+ for (y in 0 until bmp.height) {
+ for (x in 0 until bmp.width) {
+ val point = Point(x.toFloat(), y.toFloat(), 0f)
+ val ray = origin.rayTo(point)
+
+ val color = scene.colorForRay(ray)
+ if (color != null) {
+ bmp.setPixel(x, y, color.toColor())
+ }
+ }
+ }
+ File("test.tga").writeBitmap(bmp)
+}
diff --git a/src/Vector.kt b/src/main/kotlin/Vector.kt
similarity index 90%
rename from src/Vector.kt
rename to src/main/kotlin/Vector.kt
index a3f3a8f..69753c6 100644
--- a/src/Vector.kt
+++ b/src/main/kotlin/Vector.kt
@@ -11,6 +11,8 @@ data class Vector(val x: Float, val y: Float, val z: Float) {
operator fun unaryMinus(): Vector = Vector(-x, -y, -z)
operator fun minus(rhs: Vector): Vector = Vector(x - rhs.x, y - rhs.y, z - rhs.z)
operator fun div(rhs: Float): Vector = Vector(x / rhs, y / rhs, z / rhs)
+
+ infix fun dot(rhs: Vector): Float = x * rhs.x + y * rhs.y + z * rhs.z
}
operator fun Float.times(rhs: Vector): Vector = rhs * this