Proper tga.gz loading using own imagedata

src/org/newdawn/slick/opengl/ImageDataFactory.java

@@ -0,0 +1,87 @@
+package org.newdawn.slick.opengl;
+
+/**
+ * Modifications: Added support for .tga.gz
+ *
+ * Created by SKYHi14 on 2017-04-19.
+ */
+
+import net.torvald.slick.opengl.TGAGzImageData;
+import org.newdawn.slick.util.Log;
+
+import java.security.AccessController;
+import java.security.PrivilegedAction;
+
+/**
+ * A static utility to create the appropriate image data for a particular reference.
+ *
+ * @author kevin
+ */
+public class ImageDataFactory {
+    /** True if we're going to use the native PNG loader - cached so it doesn't have
+     *  the security check repeatedly
+     */
+    private static boolean usePngLoader = true;
+    /** True if the PNG loader property has been checked */
+    private static boolean pngLoaderPropertyChecked = false;
+
+    /** The name of the PNG loader configuration property */
+    private static final String PNG_LOADER = "org.newdawn.slick.pngloader";
+
+    /**
+     * Check PNG loader property. If set the native PNG loader will
+     * not be used.
+     */
+    private static void checkProperty() {
+        if (!pngLoaderPropertyChecked) {
+            pngLoaderPropertyChecked = true;
+
+            try {
+                AccessController.doPrivileged(new PrivilegedAction() {
+                    public Object run() {
+                        String val = System.getProperty(PNG_LOADER);
+                        if ("false".equalsIgnoreCase(val)) {
+                            usePngLoader = false;
+                        }
+
+                        Log.info("Use Java PNG Loader = " + usePngLoader);
+                        return null;
+                    }
+                });
+            } catch (Throwable e) {
+                // ignore, security failure - probably an applet
+            }
+        }
+    }
+
+    /**
+     * Create an image data that is appropriate for the reference supplied
+     *
+     * @param ref The reference to the image to retrieve
+     * @return The image data that can be used to retrieve the data for that resource
+     */
+    public static LoadableImageData getImageDataFor(String ref) {
+        LoadableImageData imageData;
+        checkProperty();
+
+        ref = ref.toLowerCase();
+
+        if (ref.endsWith(".tga")) {
+            return new TGAImageData();
+        }
+        if (ref.endsWith(".tga.gz")) {
+            return new TGAGzImageData();
+        }
+        if (ref.endsWith(".png")) {
+            CompositeImageData data = new CompositeImageData();
+            if (usePngLoader) {
+                data.add(new PNGImageData());
+            }
+            data.add(new ImageIOImageData());
+
+            return data;
+        }
+
+        return new ImageIOImageData();
+    }
+}