Unterschiede

Hier werden die Unterschiede zwischen zwei Versionen angezeigt.

--- api:documentation:spiele:worldtransformations [2021/06/06 22:05] – [Demo-Programm zur Methode follow] Martin Pabst
+++ api:documentation:spiele:worldtransformations [2021/12/29 11:29] (aktuell) – Externe Bearbeitung 127.0.0.1
@@ Zeile 263: / Zeile 263: @@
 </HTML>
+===== Zyklisch-parallaktisches Scrollen =====
+{{ youtube>mRgC7BJcK78?large }}
+<HTML>
+<div class="java-online" style="height: 450px; width: 100%" data-java-online="{'withBottomPanel': true, 'id': 'CyclicParalacticScroller', 'speed': 'max'}">
+<script type="text/plain" title="CyclicBackgroundTest.java">
+new CyclicBackgroundTest();
+class CyclicBackgroundTest extends Actor {
+   CyclicBackground cb1;
+   CyclicBackground cb2;
+   CyclicBackground cb3;
+   int time = 0;
+   CyclicBackgroundTest() {
+      cb1 = new CyclicBackground(new Sprite(0, 0, SpriteLibrary.Background, 2));
+      cb2 = new CyclicBackground(new Sprite(0, 0, SpriteLibrary.Background, 1));
+      cb3 = new CyclicBackground(new Sprite(0, 0, SpriteLibrary.Background, 0));
+   }
+   public void act() {
+      time++;
+      cb1.setPosition(-time, 0);
+      cb2.setPosition(-time * 2, 200);
+      cb3.setPosition(-time * 4, 400);
+   }
+}
+</script>
+<script type="text/plain" title="CyclicBackground.java">
+class CyclicBackground extends Group {
+   Sprite[] images;
+   double spriteWidth;
+   CyclicBackground(Sprite image) {
+      spriteWidth = image.getWidth();
+      int count = Math.ceil(getWorld().getWidth() / spriteWidth) + 1;
+      images = new Sprite[count];
+      image.defineCenterRelative(0, 0);
+      images[0] = image;
+      add(image);
+      for(int i = 1; i < count; i++) {
+         images[i] = image.copy();
+         add(images[i]);
+      }
+   }
+   void setPosition(double left, double top) {
+      if(left > 0) {
+         left -= Math.ceil(-left / spriteWidth) * spriteWidth;
+      }
+      double x = left + Math.floor(-left / spriteWidth) * spriteWidth;
+      for(int i = 0; i < images.length; i++){
+         images[i].moveTo(x, top);
+         x += spriteWidth;
+      }
+   }
+}
+</script>
+</div>
+</HTML>