Cleanup SplashScene class

src/main/java/org/hirw/game/SceneManager.java

@@ -4,7 +4,7 @@ import java.util.EnumMap;
 import java.util.Map;
 import lombok.Getter;
 
-final class SceneManager {
+public final class SceneManager {
   private static final SceneType DEFAULT_SCENE_TYPE = SceneType.SPLASH;
 
   private static final EnumMap<SceneType, Scene> SCENES =
@@ -19,4 +19,8 @@ final class SceneManager {
   public static void setScene(SceneType sType) {
     scene = SCENES.get(sType);
   }
+
+  public static void update() {
+    scene.update();
+  }
 }

src/main/java/org/hirw/game/SplashScene.java

@@ -6,14 +6,26 @@ import java.util.Objects;
 import org.hirw.game.util.Time;
 
 public class SplashScene extends Scene {
-  private float ramp = 0.0f;
+  private final float INITIAL_BRIGHTNESS = 0.0f;
+  private final float FADE_RATE = 0.5f;
+
+  private float brightness;
+
+  public SplashScene() {
+    this.brightness = INITIAL_BRIGHTNESS;
+  }
 
   public void update() {
     if (Objects.isNull(Window.get().getGlfwWindow())) {
       return;
     }
 
-    glClearColor(this.ramp, this.ramp, this.ramp, 0.0f);
-    this.ramp += 0.5f * Time.deltaTime();
+    fadeIn();
+  }
+
+  private void fadeIn() {
+    glClearColor(this.brightness, this.brightness, this.brightness, 0.0f);
+    final float fadeAmount = FADE_RATE * Time.deltaTime();
+    this.brightness += fadeAmount;
   }
 }

src/main/java/org/hirw/game/Window.java

@@ -90,7 +90,7 @@ public class Window {
   private void loop() {
     while (!glfwWindowShouldClose(glfwWindow)) {
       Time.update();
-      SceneManager.getScene().update();
+      SceneManager.update();
       glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
       this.shader.update();
       glfwSwapBuffers(glfwWindow);