add death animation to dying monsters

src/de/miaurizius/jgame2d/core/GamePanel.java

@@ -100,7 +100,13 @@ public class GamePanel extends JPanel implements Runnable {
             case PLAY:
                 player.update();
                 for(Entity entity : npc) if(entity != null) entity.update();
-                for(Entity entity : monster) if(entity != null) entity.update();
+                for(int i = 0; i < monster.length; i++) {
+                    Entity m = monster[i];
+                    if(m != null) {
+                        if(m.alive && !m.dying) m.update();
+                        if(!m.alive) monster[i] = null;
+                    }
+                }
                 break;
             case PAUSE:
                 break;

src/de/miaurizius/jgame2d/entity/Entity.java

@@ -33,8 +33,8 @@ public class Entity {
     public boolean collisionOn;
     public boolean invincible;
     boolean attacking;
-    boolean alive = true;
-    boolean dying;
+    public boolean alive = true;
+    public boolean dying;
 
     // COUNTER
     public int spriteCounter;
@@ -103,9 +103,9 @@ public class Entity {
                 worldY + panel.tileSize > panel.player.worldY - panel.player.screenY &&
                 worldY - panel.tileSize < panel.player.worldY + panel.player.screenY
         ) {
-            if(invincible) {
-                graphics2d.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC_OVER, 0.4f));
-            }
+            if(invincible) graphics2d.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC_OVER, 0.4f));
+
+            if(dying) dyingAnimation(graphics2d);
 
             // only modify sprite render position for player because I dont know yet how monster attack sprite are gonna look
             if(type == EntityType.PLAYER) {
@@ -120,6 +120,7 @@ public class Entity {
     }
 
     // INTERACTION
+    public void setAction() {}
     public void speak() {
         if(dialogue[dialogueIndex] == null) dialogueIndex = 0;
         panel.ui.currentDialogue = dialogue[dialogueIndex];
@@ -132,7 +133,22 @@ public class Entity {
             case RIGHT -> direction = Direction.LEFT;
         }
     }
-    public void setAction() {}
+    public void dyingAnimation(Graphics2D graphics2d) {
+        dyingCount++;
+        int incr = 5;
+        if(dyingCount <= incr) changeOpacity(graphics2d, 0f);
+        if(dyingCount > incr && dyingCount <= incr*2) changeOpacity(graphics2d, 1f);
+        if(dyingCount > incr*2 && dyingCount <= incr*3) changeOpacity(graphics2d, 0f);
+        if(dyingCount > incr*3 && dyingCount <= incr*4) changeOpacity(graphics2d, 1f);
+        if(dyingCount > incr*4 && dyingCount <= incr*5) changeOpacity(graphics2d, 0f);
+        if(dyingCount > incr*5 && dyingCount <= incr*6) changeOpacity(graphics2d, 1f);
+        if(dyingCount > incr*6 && dyingCount <= incr*7) changeOpacity(graphics2d, 0f);
+        if(dyingCount > incr*7 && dyingCount <= incr*8) changeOpacity(graphics2d, 1f);
+        if(dyingCount > incr*8) {
+            dying = false;
+            alive = false;
+        }
+    }
 
     // SETTING THINGS UP
     BufferedImage parseSprite() {
@@ -167,5 +183,8 @@ public class Entity {
         }
         return null;
     }
+    public void changeOpacity(Graphics2D graphics2d, float opacity) {
+        graphics2d.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC_OVER, opacity));
+    }
 
 }

src/de/miaurizius/jgame2d/entity/Player.java

@@ -11,7 +11,6 @@ import java.awt.*;
 public class Player extends Entity {
 
     KeyHandler keyH;
-
     public final int screenX;
     public final int screenY;
 
@@ -156,7 +155,7 @@ public class Player extends Entity {
         panel.monster[index].life -= 1;
         panel.playSE(5);
         panel.monster[index].invincible = true;
-        if(panel.monster[index].life <= 0) panel.monster[index] = null;
+        if(panel.monster[index].life <= 0) panel.monster[index].dying = true;
     }
 
     public void interactNPC(int index) {