added diffuse pathtracing

.idea/jpath.iml

@@ -0,0 +1,9 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<module type="JAVA_MODULE" version="4">
+  <component name="NewModuleRootManager" inherit-compiler-output="true">
+    <exclude-output />
+    <content url="file://$MODULE_DIR$" />
+    <orderEntry type="inheritedJdk" />
+    <orderEntry type="sourceFolder" forTests="false" />
+  </component>
+</module>

.idea/uiDesigner.xml

@@ -0,0 +1,124 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="Palette2">
+    <group name="Swing">
+      <item class="com.intellij.uiDesigner.HSpacer" tooltip-text="Horizontal Spacer" icon="/com/intellij/uiDesigner/icons/hspacer.svg" removable="false" auto-create-binding="false" can-attach-label="false">
+        <default-constraints vsize-policy="1" hsize-policy="6" anchor="0" fill="1" />
+      </item>
+      <item class="com.intellij.uiDesigner.VSpacer" tooltip-text="Vertical Spacer" icon="/com/intellij/uiDesigner/icons/vspacer.svg" removable="false" auto-create-binding="false" can-attach-label="false">
+        <default-constraints vsize-policy="6" hsize-policy="1" anchor="0" fill="2" />
+      </item>
+      <item class="javax.swing.JPanel" icon="/com/intellij/uiDesigner/icons/panel.svg" removable="false" auto-create-binding="false" can-attach-label="false">
+        <default-constraints vsize-policy="3" hsize-policy="3" anchor="0" fill="3" />
+      </item>
+      <item class="javax.swing.JScrollPane" icon="/com/intellij/uiDesigner/icons/scrollPane.svg" removable="false" auto-create-binding="false" can-attach-label="true">
+        <default-constraints vsize-policy="7" hsize-policy="7" anchor="0" fill="3" />
+      </item>
+      <item class="javax.swing.JButton" icon="/com/intellij/uiDesigner/icons/button.svg" removable="false" auto-create-binding="true" can-attach-label="false">
+        <default-constraints vsize-policy="0" hsize-policy="3" anchor="0" fill="1" />
+        <initial-values>
+          <property name="text" value="Button" />
+        </initial-values>
+      </item>
+      <item class="javax.swing.JRadioButton" icon="/com/intellij/uiDesigner/icons/radioButton.svg" removable="false" auto-create-binding="true" can-attach-label="false">
+        <default-constraints vsize-policy="0" hsize-policy="3" anchor="8" fill="0" />
+        <initial-values>
+          <property name="text" value="RadioButton" />
+        </initial-values>
+      </item>
+      <item class="javax.swing.JCheckBox" icon="/com/intellij/uiDesigner/icons/checkBox.svg" removable="false" auto-create-binding="true" can-attach-label="false">
+        <default-constraints vsize-policy="0" hsize-policy="3" anchor="8" fill="0" />
+        <initial-values>
+          <property name="text" value="CheckBox" />
+        </initial-values>
+      </item>
+      <item class="javax.swing.JLabel" icon="/com/intellij/uiDesigner/icons/label.svg" removable="false" auto-create-binding="false" can-attach-label="false">
+        <default-constraints vsize-policy="0" hsize-policy="0" anchor="8" fill="0" />
+        <initial-values>
+          <property name="text" value="Label" />
+        </initial-values>
+      </item>
+      <item class="javax.swing.JTextField" icon="/com/intellij/uiDesigner/icons/textField.svg" removable="false" auto-create-binding="true" can-attach-label="true">
+        <default-constraints vsize-policy="0" hsize-policy="6" anchor="8" fill="1">
+          <preferred-size width="150" height="-1" />
+        </default-constraints>
+      </item>
+      <item class="javax.swing.JPasswordField" icon="/com/intellij/uiDesigner/icons/passwordField.svg" removable="false" auto-create-binding="true" can-attach-label="true">
+        <default-constraints vsize-policy="0" hsize-policy="6" anchor="8" fill="1">
+          <preferred-size width="150" height="-1" />
+        </default-constraints>
+      </item>
+      <item class="javax.swing.JFormattedTextField" icon="/com/intellij/uiDesigner/icons/formattedTextField.svg" removable="false" auto-create-binding="true" can-attach-label="true">
+        <default-constraints vsize-policy="0" hsize-policy="6" anchor="8" fill="1">
+          <preferred-size width="150" height="-1" />
+        </default-constraints>
+      </item>
+      <item class="javax.swing.JTextArea" icon="/com/intellij/uiDesigner/icons/textArea.svg" removable="false" auto-create-binding="true" can-attach-label="true">
+        <default-constraints vsize-policy="6" hsize-policy="6" anchor="0" fill="3">
+          <preferred-size width="150" height="50" />
+        </default-constraints>
+      </item>
+      <item class="javax.swing.JTextPane" icon="/com/intellij/uiDesigner/icons/textPane.svg" removable="false" auto-create-binding="true" can-attach-label="true">
+        <default-constraints vsize-policy="6" hsize-policy="6" anchor="0" fill="3">
+          <preferred-size width="150" height="50" />
+        </default-constraints>
+      </item>
+      <item class="javax.swing.JEditorPane" icon="/com/intellij/uiDesigner/icons/editorPane.svg" removable="false" auto-create-binding="true" can-attach-label="true">
+        <default-constraints vsize-policy="6" hsize-policy="6" anchor="0" fill="3">
+          <preferred-size width="150" height="50" />
+        </default-constraints>
+      </item>
+      <item class="javax.swing.JComboBox" icon="/com/intellij/uiDesigner/icons/comboBox.svg" removable="false" auto-create-binding="true" can-attach-label="true">
+        <default-constraints vsize-policy="0" hsize-policy="2" anchor="8" fill="1" />
+      </item>
+      <item class="javax.swing.JTable" icon="/com/intellij/uiDesigner/icons/table.svg" removable="false" auto-create-binding="true" can-attach-label="false">
+        <default-constraints vsize-policy="6" hsize-policy="6" anchor="0" fill="3">
+          <preferred-size width="150" height="50" />
+        </default-constraints>
+      </item>
+      <item class="javax.swing.JList" icon="/com/intellij/uiDesigner/icons/list.svg" removable="false" auto-create-binding="true" can-attach-label="false">
+        <default-constraints vsize-policy="6" hsize-policy="2" anchor="0" fill="3">
+          <preferred-size width="150" height="50" />
+        </default-constraints>
+      </item>
+      <item class="javax.swing.JTree" icon="/com/intellij/uiDesigner/icons/tree.svg" removable="false" auto-create-binding="true" can-attach-label="false">
+        <default-constraints vsize-policy="6" hsize-policy="6" anchor="0" fill="3">
+          <preferred-size width="150" height="50" />
+        </default-constraints>
+      </item>
+      <item class="javax.swing.JTabbedPane" icon="/com/intellij/uiDesigner/icons/tabbedPane.svg" removable="false" auto-create-binding="true" can-attach-label="false">
+        <default-constraints vsize-policy="3" hsize-policy="3" anchor="0" fill="3">
+          <preferred-size width="200" height="200" />
+        </default-constraints>
+      </item>
+      <item class="javax.swing.JSplitPane" icon="/com/intellij/uiDesigner/icons/splitPane.svg" removable="false" auto-create-binding="false" can-attach-label="false">
+        <default-constraints vsize-policy="3" hsize-policy="3" anchor="0" fill="3">
+          <preferred-size width="200" height="200" />
+        </default-constraints>
+      </item>
+      <item class="javax.swing.JSpinner" icon="/com/intellij/uiDesigner/icons/spinner.svg" removable="false" auto-create-binding="true" can-attach-label="true">
+        <default-constraints vsize-policy="0" hsize-policy="6" anchor="8" fill="1" />
+      </item>
+      <item class="javax.swing.JSlider" icon="/com/intellij/uiDesigner/icons/slider.svg" removable="false" auto-create-binding="true" can-attach-label="false">
+        <default-constraints vsize-policy="0" hsize-policy="6" anchor="8" fill="1" />
+      </item>
+      <item class="javax.swing.JSeparator" icon="/com/intellij/uiDesigner/icons/separator.svg" removable="false" auto-create-binding="false" can-attach-label="false">
+        <default-constraints vsize-policy="6" hsize-policy="6" anchor="0" fill="3" />
+      </item>
+      <item class="javax.swing.JProgressBar" icon="/com/intellij/uiDesigner/icons/progressbar.svg" removable="false" auto-create-binding="true" can-attach-label="false">
+        <default-constraints vsize-policy="0" hsize-policy="6" anchor="0" fill="1" />
+      </item>
+      <item class="javax.swing.JToolBar" icon="/com/intellij/uiDesigner/icons/toolbar.svg" removable="false" auto-create-binding="false" can-attach-label="false">
+        <default-constraints vsize-policy="0" hsize-policy="6" anchor="0" fill="1">
+          <preferred-size width="-1" height="20" />
+        </default-constraints>
+      </item>
+      <item class="javax.swing.JToolBar$Separator" icon="/com/intellij/uiDesigner/icons/toolbarSeparator.svg" removable="false" auto-create-binding="false" can-attach-label="false">
+        <default-constraints vsize-policy="0" hsize-policy="0" anchor="0" fill="1" />
+      </item>
+      <item class="javax.swing.JScrollBar" icon="/com/intellij/uiDesigner/icons/scrollbar.svg" removable="false" auto-create-binding="true" can-attach-label="false">
+        <default-constraints vsize-policy="6" hsize-policy="0" anchor="0" fill="2" />
+      </item>
+    </group>
+  </component>
+</project>

src/main/java/basics/math/algebra/Basis.java

@@ -0,0 +1,36 @@
+package basics.math.algebra;
+
+/**
+ * Basis of an vector space.
+ * This class owns the components of a vector space.
+ */
+public class Basis {
+
+    public Vector[] vectors;
+
+    public Basis(Vector[] vectors) {
+        this.vectors = vectors;
+    }
+
+    public Basis(Vector a, Vector b, Vector c) {
+        this.vectors = new Vector[]{a, b, c};
+    }
+
+    /**
+     * Constructs an orthonormal basis using the gram-schmidt formula.
+     * It will utilize the supplied up vector as the first basis vector,
+     * building the other two vectors from swizzling the up vectors components.
+     *
+     * @param up the first vector of this basis
+     * @return an orthonormal basis with up and 2 additional orthonormal vectors
+     */
+    public static Basis constructOrthonormalBasis(Vector up) {
+        Vector n2 = Vector.diagonal(1).sub(up);
+        Vector n3 = Vector.diagonal(1).sub(up.shuffle(Vector.SwizzleMask.ZXY));
+
+        Vector w2 = n2.sub(up.project(n2)).normalize();
+        Vector w3 = n3.sub(up.project(n3)).sub(w2.project(n3)).normalize();
+
+        return new Basis(up, w2, w3);
+    }
+}

src/main/java/basics/math/algebra/Vector.java

@@ -96,6 +96,10 @@ public class Vector {
         );
     }
 
+    public Vector project(Vector other) {
+        return this.scale(other.dot(this) / this.dot(this));
+    }
+
     public Vector reflect(Vector normal) {
         return this.sub(normal.scale(this.dot(normal) * 2.0));
     }

src/main/java/entry/Main.java

@@ -1,21 +1,22 @@
 package entry;
 
 import optics.view.PlayerController;
-import raytracing.Raytracer;
+import pathtracing.Pathtracer;
 import renderer.Display;
+import renderer.Renderer;
 import renderer.Resolution;
 
 public class Main {
 
     public static void main(String[] args) {
 
-        Resolution resolution = new Resolution(800, 800, 3);
+        Resolution resolution = new Resolution(800, 800, 6);
 
         PlayerController controller = new PlayerController();
 
         Display display = new Display(resolution, controller);
 
-        Raytracer raytracer = new Raytracer();
+        Renderer raytracer = new Pathtracer();
 
         display.start(raytracer, controller);
     }

src/main/java/geometry/scene/Scene.java

@@ -6,6 +6,7 @@ import optics.light.Color;
 import optics.light.Directional;
 import optics.light.LightSource;
 import optics.light.Point;
+import pathtracing.BSDF;
 import raytracing.BasicMaterial;
 import renderer.mesh.BasicMesh;
 import renderer.mesh.Mesh;
@@ -29,7 +30,7 @@ public class Scene {
         this.lights = new ArrayList<>();
     }
 
-    public static Scene generateExampleScene() {
+    public static Scene generateRaytracingExampleScene() {
         Scene scene = new Scene(new LinearList());
 
         BasicMaterial glass = new BasicMaterial(Color.BLACK, 1.0, Color.WHITE, true);
@@ -58,6 +59,33 @@ public class Scene {
         return scene;
     }
 
+    public static Scene generatePathtracingExampleScene() {
+        Scene scene = new Scene(new LinearList());
+
+        BSDF red = new BSDF(new Color(1, 0.3, 0.3), new Color(0), 1.0);
+        BSDF green = new BSDF(new Color(0.3,1, 0.3), new Color(0), 1);
+        BSDF blue = new BSDF(new Color(0.3, 0.3, 1), new Color(0), 1);
+        BSDF white = new BSDF(new Color(1, 1, 1), new Color(0), 1);
+        BSDF light = new BSDF(Color.BLACK, new Color(300), 1.0);
+
+        scene.addMesh(new BasicMesh(white, new Sphere(new Vector(0,0,0), 1.0)));
+        scene.addMesh(new BasicMesh(white, new Sphere(new Vector(3,2,1), 1.0)));
+
+        scene.addMesh(new BasicMesh(white, new Plane(new Vector(0, 1, 0), 1)));
+        scene.addMesh(new BasicMesh(white, new Plane(new Vector(0, 1, 0), -6)));
+
+        scene.addMesh(new BasicMesh(red, new Plane(new Vector(-1, 0, 0), 4)));
+        scene.addMesh(new BasicMesh(green, new Plane(new Vector(-1, 0, 0), -4)));
+
+        scene.addMesh(new BasicMesh(blue, new Plane(new Vector(0, 0, 1), 5)));
+        scene.addMesh(new BasicMesh(white, new Plane(new Vector(0, 0, 1), -4)));
+
+        scene.addMesh(new BasicMesh(light, new Sphere(new Vector(0,6.0,0), 1.0)));
+        //scene.addLight(new Point(Color.WHITE.scale(1.0), new Vector(0, 4, 0)));
+
+        return scene;
+    }
+
     public void addLight(LightSource light) {
         this.lights.add(light);
     }

src/main/java/optics/light/Color.java

@@ -108,6 +108,24 @@ public class Color {
         return this.scale(k).add(other.scale(1.0 - k));
     }
 
+    public void colorCorrect() {
+        this.r = tonemap(this.r);
+        this.g = tonemap(this.g);
+        this.b = tonemap(this.b);
+    }
+
+    private double tonemap(double k) {
+        return -1 / (k + 1) + 1;
+    }
+
+    public int getIntRGB() {
+        int r = (int) (this.r * 255);
+        int g = (int) (this.g * 255);
+        int b = (int) (this.b * 255);
+
+        return 0xff000000 | (r << 16) | (g << 8) | b;
+    }
+
     public enum SwizzleMask {
         rgb,
         grb,

src/main/java/pathtracing/BSDF.java

@@ -0,0 +1,30 @@
+package pathtracing;
+
+import optics.light.Color;
+import shading.Material;
+
+public class BSDF implements Material {
+
+    private Color reflectance;
+    private Color emission;
+
+    private double roughness;
+
+    public BSDF(Color reflectance, Color emission, double roughness) {
+        this.reflectance = reflectance;
+        this.emission = emission;
+        this.roughness = roughness;
+    }
+
+    public Color getReflectance() {
+        return reflectance;
+    }
+
+    public Color getEmission() {
+        return emission;
+    }
+
+    public double getRoughness() {
+        return roughness;
+    }
+}

src/main/java/pathtracing/Pathtracer.java

@@ -0,0 +1,120 @@
+package pathtracing;
+
+import basics.math.algebra.Basis;
+import basics.math.algebra.Ray;
+import basics.math.algebra.Vector;
+import geometry.scene.Hit;
+import geometry.scene.Scene;
+import optics.light.Color;
+import optics.light.LightSource;
+import optics.view.Camera;
+import optics.view.PinholeCamera;
+import renderer.Renderer;
+
+import java.util.Optional;
+
+public class Pathtracer implements Renderer {
+
+    private final Camera camera = new PinholeCamera(new Vector(0,0,-4), Vector.origin(), 90, 1e-3, 1e3);
+    private final Scene scene = Scene.generatePathtracingExampleScene();
+
+    private double traceShadow(Vector point, Vector direction, double distance) {
+        Ray shadowRay = new Ray(point, direction, 1e-3, distance);
+
+        Optional<Hit> result = scene.intersect(shadowRay);
+
+        if (result.isEmpty()) {
+            return 1.0;
+        }
+
+        return 0.0;
+    }
+
+    private double castShadow(LightSource target, Vector point, Vector surfaceNormal) {
+        Vector lightDirection = target.getDirection(point);
+        double distance = target.getDistance(point);
+        double shadow = traceShadow(point, lightDirection, distance);
+        return Math.max(surfaceNormal.dot(lightDirection), 0.0) * shadow;
+    }
+
+    private Color traceDirect(Ray directRay, int depth) {
+        if (depth == 8) {
+            return Color.BLACK;
+        }
+
+        Optional<Hit> result = scene.intersect(directRay);
+
+        if (result.isEmpty()) {
+            // Background color
+            return Color.BLACK;
+        }
+
+        Vector intersection = directRay.travel(result.get().getDistance());
+        Vector normal = result.get().getMesh().normalAt(intersection, directRay.getDirection());
+
+        BSDF material = (BSDF) result.get().getMesh().getMaterial();
+
+        var diffuse = diffuseCosineWeightedBRDF(intersection, normal, material, depth);
+
+        return diffuse.add(material.getEmission());
+    }
+
+    private Color diffuseCosineWeightedBRDF(Vector intersection, Vector normal, BSDF bsdf, int depth) {
+        var next = new Ray(intersection, sampleNormalHemisphere(normal, bsdf.getRoughness()), 1e-3, 1e3);
+
+        var cosTheta = next.getDirection().dot(normal);
+
+        var pdf = cosTheta / Math.PI;
+
+        var indirectLight = traceDirect(next, depth + 1).scale(pdf);
+
+        // direct light
+
+        Color directLight = Color.BLACK;
+
+        for (LightSource light : scene.getLights()) {
+            double directInfluence = castShadow(light, intersection, normal);
+
+            Color incoming = bsdf.getReflectance().scale(directInfluence).mul(light.getColor());
+
+            directLight = directLight.add(incoming);
+        }
+
+        return bsdf.getReflectance().mul(indirectLight.add(directLight));
+    }
+
+    private Vector cosineHemisphere() {
+        double u1 = Math.random();
+        double u2 = Math.random();
+
+        double r = Math.sqrt(u1);
+        double theta = 2 * Math.PI * u2;
+
+        double x = r * Math.cos(theta);
+        double y = r * Math.sin(theta);
+
+        return new Vector(x, y, Math.sqrt(1 - u1));
+    }
+
+    private Vector sampleNormalHemisphere(Vector normal, double roughness) {
+        Vector hemisphereSample = cosineHemisphere();
+
+        var orthnormalBasis = Basis.constructOrthonormalBasis(normal);
+
+        return orthnormalBasis.vectors[0].scale(hemisphereSample.z)
+                .add(orthnormalBasis.vectors[1].scale(hemisphereSample.x))
+                .add(orthnormalBasis.vectors[2].scale(hemisphereSample.y));
+    }
+
+    @Override
+    public Color traceCameraRay(double u, double v) {
+        var cameraRay = camera.generateViewRay(u, v);
+
+        return traceDirect(cameraRay, 0);
+    }
+
+    @Override
+    public Camera getCamera() {
+        return camera;
+    }
+}

src/main/java/raytracing/Raytracer.java

@@ -14,8 +14,8 @@ import java.util.Optional;
 
 public class Raytracer implements Renderer {
 
-    private Camera camera = new PinholeCamera(new Vector(0,0,-4), Vector.origin(), 90, 1e-3, 1e3);
+    private final Camera camera = new PinholeCamera(new Vector(0,0,-4), Vector.origin(), 90, 1e-3, 1e3);
-    private Scene scene = Scene.generateExampleScene();
+    private final Scene scene = Scene.generateRaytracingExampleScene();
 
     private double traceShadow(Vector point, Vector direction, double distance) {
         Ray shadowRay = new Ray(point, direction, 1e-3, distance);
@@ -50,7 +50,12 @@ public class Raytracer implements Renderer {
         Color incoming = new Color(0,0,0);
 
         if (material.refracts()) {
-            return refractedLight(directRay, material, normal, intersection, depth);
+            var reflection = reflectedLight(directRay, material, normal, intersection, depth);
+            var refraction = refractedLight(directRay, material, normal, intersection, depth);
+
+            var fac = -directRay.getDirection().dot(normal);
+
+            return refraction.lerp(reflection, Math.pow(fac, 0.5));
         }
 
         Color reflectedLight = reflectedLight(directRay, material, normal, intersection, depth);
@@ -77,9 +82,7 @@ public class Raytracer implements Renderer {
     private Color refractedLight(Ray incomingRay, BasicMaterial material, Vector normal, Vector point, int depth) {
         Vector refracted = incomingRay.getDirection().refract(normal, incomingRay.getDirection(), 1.45);
 
-        Color refractedLight = traceDirect(new Ray(point, refracted, 1e-3, incomingRay.getFar()), depth + 1);
+        return traceDirect(new Ray(point, refracted, 1e-3, incomingRay.getFar()), depth + 1);
-
-        return refractedLight;
     }
 
     private double castShadow(LightSource target, Vector point, Vector surfaceNormal) {

src/main/java/renderer/Display.java

@@ -4,9 +4,12 @@ import optics.light.Color;
 import optics.view.PlayerController;
 import renderer.canvas.RenderTarget;
 
+import javax.imageio.ImageIO;
 import javax.swing.*;
 import java.awt.*;
 import java.awt.event.*;
+import java.awt.image.RenderedImage;
+import java.io.File;
 
 public class Display {
 
@@ -19,6 +22,7 @@ public class Display {
 
     private int sampleCount;
     private long frametime;
+    private long startTime;
 
     public Display(Resolution resolution, PlayerController controller) {
         this.resolution = resolution;
@@ -86,9 +90,16 @@ public class Display {
         try (Scheduler scheduler = Scheduler.getInstance()) {
             var tasks = scheduler.generateTasks(this.target, program);
 
+            startTime = System.currentTimeMillis();
+
             while (!this.close) {
                 this.frametime = System.currentTimeMillis();
 
+                if (System.currentTimeMillis() - startTime > 1000 * 60 * 20) {
+                    ImageIO.write(this.target.getImage(), "png", new File("images/" + System.currentTimeMillis() + ".png"));
+                    System.exit(0);
+                }
+
                 if (resized) {
                     this.resolution.setSize(window.getSize());
                     // Window has been resized, rebuild drawing buffer
@@ -128,5 +139,6 @@ public class Display {
         overlay.setThreads();
         overlay.setFrametime(this.frametime);
         overlay.setSamples(sampleCount);
+        overlay.setTime(System.currentTimeMillis() - startTime);
     }
 }

src/main/java/renderer/TileProcessor.java

@@ -1,22 +1,20 @@
 package renderer;
 
-import basics.math.algebra.Vector;
 import renderer.canvas.ContributionBuffer;
-
 import java.util.concurrent.Callable;
 
 public class TileProcessor implements Callable<Void> {
 
     private final ContributionBuffer buffer;
 
-    private FragmentProgram program;
+    private final FragmentProgram program;
 
-    private int width;
+    private final int width;
-    private int height;
+    private final int height;
-    private int x0;
+    private final int x0;
-    private int y0;
+    private final int y0;
-    private int x1;
+    private final int x1;
-    private int y1;
+    private final int y1;
 
     public TileProcessor(ContributionBuffer buffer, int x0, int y0, int x1, int y1, int width, int height, FragmentProgram program) {
         this.buffer = buffer;
@@ -30,13 +28,15 @@ public class TileProcessor implements Callable<Void> {
     }
 
     @Override
-    public Void call() throws Exception {
+    public Void call() {
+        double widthTransform = 1.0 / (double) this.width * 2.0;
+        double heightTransform = 1.0 / (double) this.height * 2.0;
 
         for (int x = this.x0; x < x1; x++) {
-            double u = (x + Math.random()) / (double) this.width * 2.0 - 1.0;
+            double u = (x + Math.random()) * widthTransform - 1.0;
 
             for (int y = this.y0; y < y1; y++) {
-                double v = (y + Math.random()) / (double) this.height * 2.0 - 1.0;
+                double v = (y + Math.random()) * heightTransform - 1.0;
 
                 this.buffer.contribute(x, y, this.program.fragment(u, v));
             }

src/main/java/renderer/canvas/ContributionBuffer.java

@@ -13,6 +13,8 @@ public class ContributionBuffer {
     private int width;
     private int height;
 
+    private int maxSample;
+
     public ContributionBuffer(int width, int height) {
         this.width = width;
         this.height = height;
@@ -30,6 +32,8 @@ public class ContributionBuffer {
     public void contribute(int x, int y, Color color) {
         buffer[x][y] = buffer[x][y].add(color);
         samples[x][y]++;
+
+        maxSample = Math.max(maxSample, (int) samples[x][y]);
     }
 
     /**
@@ -51,6 +55,8 @@ public class ContributionBuffer {
     private int getRGB(int x, int y) {
         Color linearRGB = buffer[x][y].scale(1.0 / samples[x][y]);
 
+        linearRGB.colorCorrect();
+
         int red = (int) (linearRGB.r* 255.0);
         int green = (int) (linearRGB.g * 255.0);
         int blue = (int) (linearRGB.b * 255.0);
@@ -62,6 +68,20 @@ public class ContributionBuffer {
         return 0xff000000 | red << 16 | green << 8 | blue;
     }
 
+    public Color getPixel(int x, int y) {
+        return buffer[x][y].scale(1.0 / samples[x][y]);
+    }
+
+    public void visualizeSamples(int[] buffer) {
+        for (int y = 0; y < height; y++) {
+            int col = y * width;
+
+            for (int x = 0; x < width; x++) {
+                buffer[col + x] = Color.diagonal(samples[x][y] / maxSample).getIntRGB();
+            }
+        }
+    }
+
     public void blit(int[] buffer) {
         for (int y = 0; y < height; y++) {
             int col = y * width;

src/main/java/renderer/canvas/RenderTarget.java

@@ -1,6 +1,5 @@
 package renderer.canvas;
 
-import optics.view.PlayerController;
 import renderer.Resolution;
 import renderer.Scheduler;
 import renderer.debug.DebugOverlay;
@@ -9,6 +8,7 @@ import javax.swing.*;
 import java.awt.*;
 import java.awt.image.BufferedImage;
 import java.awt.image.DataBufferInt;
+import java.awt.image.RenderedImage;
 
 public class RenderTarget extends JPanel {
 
@@ -70,4 +70,8 @@ public class RenderTarget extends JPanel {
     public DebugOverlay getOverlay() {
         return overlay;
     }
+
+    public RenderedImage getImage() {
+        return this.target;
+    }
 }

src/main/java/renderer/debug/DebugOverlay.form

@@ -8,7 +8,7 @@
     <properties/>
     <border type="none"/>
     <children>
-      <grid id="eb7a2" layout-manager="GridLayoutManager" row-count="7" column-count="2" same-size-horizontally="false" same-size-vertically="false" hgap="-1" vgap="-1">
+      <grid id="eb7a2" layout-manager="GridLayoutManager" row-count="8" column-count="2" same-size-horizontally="false" same-size-vertically="false" hgap="-1" vgap="-1">
         <margin top="0" left="8" bottom="0" right="8"/>
         <constraints>
           <grid row="0" column="0" row-span="9" col-span="1" vsize-policy="3" hsize-policy="3" anchor="0" fill="3" indent="0" use-parent-layout="false"/>
@@ -26,7 +26,7 @@
           </component>
           <vspacer id="8c764">
             <constraints>
-              <grid row="6" column="0" row-span="1" col-span="1" vsize-policy="6" hsize-policy="1" anchor="0" fill="2" indent="0" use-parent-layout="false"/>
+              <grid row="7" column="0" row-span="1" col-span="1" vsize-policy="6" hsize-policy="1" anchor="0" fill="2" indent="0" use-parent-layout="false"/>
             </constraints>
           </vspacer>
           <component id="4bbcc" class="javax.swing.JLabel">
@@ -117,6 +117,22 @@
               <text value="866"/>
             </properties>
           </component>
+          <component id="f3105" class="javax.swing.JLabel" binding="time">
+            <constraints>
+              <grid row="6" column="1" row-span="1" col-span="1" vsize-policy="0" hsize-policy="0" anchor="8" fill="0" indent="0" use-parent-layout="false"/>
+            </constraints>
+            <properties>
+              <text value="Label"/>
+            </properties>
+          </component>
+          <component id="951eb" class="javax.swing.JLabel">
+            <constraints>
+              <grid row="6" column="0" row-span="1" col-span="1" vsize-policy="0" hsize-policy="0" anchor="8" fill="0" indent="0" use-parent-layout="false"/>
+            </constraints>
+            <properties>
+              <text value="Time"/>
+            </properties>
+          </component>
         </children>
       </grid>
       <hspacer id="6cc64">

src/main/java/renderer/debug/DebugOverlay.java

@@ -14,6 +14,7 @@ public class DebugOverlay {
     private JLabel samples;
     private JPanel root;
     private JLabel downScale;
+    private JLabel time;
 
     public void setup(){
         this.root.setOpaque(false);
@@ -44,4 +45,8 @@ public class DebugOverlay {
     public JPanel getRoot() {
         return root;
     }
+
+    public void setTime(long l) {
+        this.time.setText(String.format("%.1fs", l * 1e-3));
+    }
 }

src/main/java/renderer/mesh/BasicMesh.java

@@ -8,11 +8,11 @@ import shading.Material;
 
 public class BasicMesh extends Mesh {
 
-    private BasicMaterial material;
+    private Material material;
 
     private Primitive shape;
 
-    public BasicMesh(BasicMaterial material, Primitive shape) {
+    public BasicMesh(Material material, Primitive shape) {
         this.material = material;
         this.shape = shape;
     }