Added a method to create a shader state using Files and preprocessor

definitions.


git-svn-id: svn+ssh://src.earth.threerings.net/nenya/trunk@159 ed5b42cb-e716-0410-a449-f6a68f950b19

src/java/com/threerings/jme/util/JmeUtil.java

@@ -21,8 +21,15 @@
 
 package com.threerings.jme.util;
 
+import java.io.BufferedReader;
+import java.io.File;
+import java.io.FileReader;
+import java.io.IOException;
+
 import com.jme.math.Vector3f;
 import com.jme.scene.Controller;
+import com.jme.scene.state.GLSLShaderObjectsState;
+import com.jme.system.DisplaySystem;
 
 import com.samskivert.util.StringUtil;
 
@@ -156,4 +163,44 @@ public class JmeUtil
         }
         return defaultType;
     }
+
+    /**
+     * Loads the specified shaders (prepending the supplied preprocessor definitions)
+     * and returns a GLSL shader state.  One of the supplied files may be <code>null</code>
+     * in order to use the fixed-function pipeline for that part.
+     *
+     * @param defs a number of preprocessor definitions to be #defined in both shaders
+     * (e.g., "ENABLE_FOG", "NUM_LIGHTS 2").
+     */
+    public static GLSLShaderObjectsState loadShaders (File vert, File frag, String... defs)
+    {
+        GLSLShaderObjectsState sstate =
+            DisplaySystem.getDisplaySystem().getRenderer().createGLSLShaderObjectsState();
+        sstate.load(
+            (vert == null) ? null : readSource(vert, defs),
+            (frag == null) ? null : readSource(frag, defs));
+        return sstate;
+    }
+
+    /**
+     * Loads an entire source file as a string, prepending the supplied preprocessor definitions.
+     */
+    protected static String readSource (File file, String[] defs)
+    {
+        StringBuffer buf = new StringBuffer();
+        String ln = System.getProperty("line.separator");
+        for (String def : defs) {
+            buf.append("#define ").append(def).append(ln);
+        }
+        try {
+            BufferedReader reader = new BufferedReader(new FileReader(file));
+            String line;
+            while ((line = reader.readLine()) != null) {
+                buf.append(line).append(ln);
+            }
+        } catch (IOException e) {
+            return null;
+        }
+        return buf.toString();
+    }
 }