make renders (almost) deterministic

src/main/java/eu/jonahbauer/raytracing/render/renderer/SimpleRenderer.java

@@ -62,7 +62,7 @@ public final class SimpleRenderer implements Renderer {
      * a time and updating the canvas after each sample.
      */
     private void renderIterative(@NotNull Camera camera, @NotNull Scene scene, @NotNull Canvas canvas) {
-        var random = new Random();
+        var random = new Random(0);
 
         // render one sample after the other
         int i = 0;
@@ -94,7 +94,7 @@ public final class SimpleRenderer implements Renderer {
      * per pixel and updating the canvas after each pixel.
      */
     private void renderNonIterative(@NotNull Camera camera, @NotNull Scene scene, @NotNull Canvas canvas) {
-        var splittable = new SplittableRandom();
+        var splittable = new SplittableRandom(0);
         // render one pixel after the other
         getScanlineStream(camera.getHeight(), parallel).forEach(y -> {
             var random = splittable.split();