From 3fbff7890c9feedc890f30fe1a8cf41ba2ead722 Mon Sep 17 00:00:00 2001
From: Jan Philipp Timme <jan.philipp@timme.it>
Date: Tue, 25 Nov 2014 15:18:11 +0100
Subject: [PATCH] Create the ScrollingBackground class. TODO: Optimize!

---
 .../background/ScrollingBackground.java       | 61 +++++++++++++++++++
 .../background/StarBackground.java            | 33 +---------
 2 files changed, 63 insertions(+), 31 deletions(-)
 create mode 100644 src/de/teamteamteam/spacescooter/background/ScrollingBackground.java

diff --git a/src/de/teamteamteam/spacescooter/background/ScrollingBackground.java b/src/de/teamteamteam/spacescooter/background/ScrollingBackground.java
new file mode 100644
index 0000000..fa0b939
--- /dev/null
+++ b/src/de/teamteamteam/spacescooter/background/ScrollingBackground.java
@@ -0,0 +1,61 @@
+package de.teamteamteam.spacescooter.background;
+
+import java.awt.Graphics2D;
+
+import de.teamteamteam.spacescooter.utility.GameConfig;
+
+public class ScrollingBackground extends Background {
+
+	/**
+	 * Speed the background scrolls through with.
+	 */
+	private int scrollingSpeed;
+	
+	/**
+	 * Internal offset counter to determine how much the Background scrolled.
+	 */
+	private int offset;
+	
+	
+	/**
+	 * Default constructor.
+	 */
+	public ScrollingBackground(int x, int y) {
+		super(x, y);
+		this.offset = 0;
+	}
+	
+
+	/**
+	 * Set the scrolling speed to use for this Background.
+	 */
+	public void setScrollingSpeed(int scrollingSpeed) {
+		this.scrollingSpeed = scrollingSpeed;
+	}
+	
+	/**
+	 * Apply the scrolling effect by updating an internal offset counter.
+	 * Reset it when we scrolled for one image length.
+	 */
+	public void update() {
+		this.offset += this.scrollingSpeed;
+		if(Math.abs(this.offset) > this.getImage().getWidth()) {
+			this.offset += this.getImage().getWidth();
+		}
+	}
+	
+	/**
+	 * Paint the Background. Concatenate the image if necessary, but still try
+	 * to save ressources.
+	 * TODO: Huge performance improvements using the tons of param version of drawImage!
+	 */
+	public void paint(Graphics2D g) {
+		int i = 0;
+		int wWidth = GameConfig.windowWidth;
+		while((i*this.getImage().getWidth()+this.offset) < wWidth) {
+			g.drawImage(this.getImage(), (i*this.getImage().getWidth()+this.offset), this.getY(), null);
+			i++;
+		}
+	}
+
+}
diff --git a/src/de/teamteamteam/spacescooter/background/StarBackground.java b/src/de/teamteamteam/spacescooter/background/StarBackground.java
index b61febf..ec22cba 100644
--- a/src/de/teamteamteam/spacescooter/background/StarBackground.java
+++ b/src/de/teamteamteam/spacescooter/background/StarBackground.java
@@ -1,46 +1,17 @@
 package de.teamteamteam.spacescooter.background;
 
-import java.awt.Graphics2D;
-
 /**
  * The StarBackground of the first level
  */
-public class StarBackground extends Background {
-	
-	private int y;
+public class StarBackground extends ScrollingBackground {
 	
 	/**
 	 * Constructor for the background
 	 */
 	public StarBackground(int x, int y) {
 		super(x, y);
-		this.y = y;
 		this.setImage("images/starbackground.png");
+		this.setScrollingSpeed(-2);
 	}
 
-	/**
-	 * offset in x-direction for the painting
-	 */
-	private int offset = 0;
-	
-	/**
-	 * standart update method
-	 */
-	public void update() {
-		this.offset -= 2;
-		//System.out.println(this.offset);
-		if(Math.abs(this.offset) > this.getImage().getWidth()) {
-			this.offset += this.getImage().getWidth();
-		}
-	}
-	
-	/**
-	 * standart paint method
-	 */
-	public void paint(Graphics2D g) {
-		g.drawImage(this.getImage(), (0+this.offset), this.y, null);
-		g.drawImage(this.getImage(), (this.getImage().getWidth()+this.offset), this.y, null);
-		g.drawImage(this.getImage(), (2*this.getImage().getWidth()+this.offset), this.y, null);
-	}
-	
 }