add antialiasing

src/main/java/eu/jonahbauer/raytracing/render/Camera.java

@@ -21,6 +21,9 @@ public final class Camera {
     private final @NotNull Vec3 origin;
     private final @NotNull Vec3 direction;
 
+    // antialiasing
+    private final int samplesPerPixel = 100;
+
     // internal properties
     private final @NotNull Vec3 pixelU;
     private final @NotNull Vec3 pixelV;
@@ -86,10 +89,20 @@ public final class Camera {
         var image = new Image(width, height);
 
         for (int y = 0; y < height; y++) {
-                var ray = getRay(x, y);
-                var color = getColor(scene, ray);
-                image.set(x, y, color);
             for (int x = 0; x < width; x++) {
+                var r = 0d;
+                var g = 0d;
+                var b = 0d;
+
+                for (int i = 0; i < samplesPerPixel; i++) {
+                    var ray = getRay(x, y);
+                    var color = getColor(scene, ray);
+                    r += color.r();
+                    g += color.g();
+                    b += color.b();
+                }
+
+                image.set(x, y, new Color(r / samplesPerPixel, g / samplesPerPixel, b / samplesPerPixel));
             }
         }
 
@@ -103,7 +116,10 @@ public final class Camera {
     private @NotNull Vec3 getPixel(int x, int y) {
         Objects.checkIndex(x, width);
         Objects.checkIndex(y, height);
-        return pixel00.plus(pixelU.times(x)).plus(pixelV.times(y));
+
+        double dx = x + Math.random() - 0.5;
+        double dy = y + Math.random() - 0.5;
+        return pixel00.plus(pixelU.times(dx)).plus(pixelV.times(dy));
     }
 
     private @NotNull Color getColor(@NotNull Scene scene, @NotNull Ray ray) {