Basic support for skinning with GLSL shaders. Still need to work out

how to handle different lighting arrangements and complex materials 
(e.g., the metal effect for the Iron Plate).


git-svn-id: svn+ssh://src.earth.threerings.net/nenya/trunk@229 ed5b42cb-e716-0410-a449-f6a68f950b19

rsrc/media/jme/skin.vert

@@ -0,0 +1,85 @@
+//
+// $Id: ImageCache.java 158 2007-02-24 00:38:17Z mdb $
+//
+// Nenya library - tools for developing networked games
+// Copyright (C) 2002-2007 Three Rings Design, Inc., All Rights Reserved
+// http://www.threerings.net/code/nenya/
+//
+// This library is free software; you can redistribute it and/or modify it
+// under the terms of the GNU Lesser General Public License as published
+// by the Free Software Foundation; either version 2.1 of the License, or
+// (at your option) any later version.
+//
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+// Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public
+// License along with this library; if not, write to the Free Software
+// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+
+#version 110
+
+#if BONES_PER_VERTEX == 4
+    #define ATTRIB_TYPE vec4
+#elif BONES_PER_VERTEX == 3
+    #define ATTRIB_TYPE vec3
+#elif BONES_PER_VERTEX == 2
+    #define ATTRIB_TYPE vec2
+#else
+    #define ATTRIB_TYPE float
+#endif
+
+/** The bone transforms. */
+uniform mat4 boneTransforms[MAX_BONE_COUNT];
+
+/** The bone indices. */
+attribute ATTRIB_TYPE boneIndices;
+
+/** The bone weights. */
+attribute ATTRIB_TYPE boneWeights;
+
+/**
+ * Vertex shader for skinned meshes.
+ */
+void main ()
+{
+    vec4 normal4 = vec4(gl_Normal, 0.0);
+
+    // add up the vertex as transformed by each bone and scaled by each weight
+    #if BONES_PER_VERTEX == 1
+        vec4 skinVertex = boneTransforms[int(boneIndices)] * gl_Vertex;
+        vec4 skinNormal = boneTransforms[int(boneIndices)] * normal4;
+    #else
+        vec4 skinVertex = boneTransforms[int(boneIndices[0])] * gl_Vertex * boneWeights[0];
+        vec4 skinNormal = boneTransforms[int(boneIndices[0])] * normal4 * boneWeights[0];
+        for (int ii = 1; ii < BONES_PER_VERTEX; ii++) {
+            skinVertex += boneTransforms[int(boneIndices[ii])] * gl_Vertex * boneWeights[ii];
+            skinNormal += boneTransforms[int(boneIndices[ii])] * normal4 * boneWeights[ii];
+        }
+    #endif
+
+    // copy the texture coordinates from attribute to varying
+    gl_TexCoord[0] = gl_MultiTexCoord0;
+    gl_TexCoord[1] = gl_MultiTexCoord1;
+
+    // apply the standard transformation
+    gl_Position = gl_ModelViewProjectionMatrix * skinVertex;
+
+    // eye space 'z' is the standard fog coordinate
+    gl_FogFragCoord = -dot(gl_ModelViewMatrixTranspose[2], skinVertex);
+
+    // transform the normal into eye space
+    vec3 eyeNormal = normalize(vec3(gl_ModelViewMatrixInverseTranspose * skinNormal));
+
+    // set gl_FrontColor based on normal and light parameters
+    gl_FrontColor.rgb =
+        gl_FrontLightProduct[0].ambient.rgb +
+        gl_FrontLightProduct[0].diffuse.rgb *
+            max(dot(eyeNormal, gl_LightSource[0].position.xyz), 0.0) +
+        gl_FrontLightProduct[1].ambient.rgb +
+        gl_FrontLightProduct[1].diffuse.rgb *
+            max(dot(eyeNormal, gl_LightSource[1].position.xyz), 0.0);
+    gl_FrontColor.a = gl_FrontMaterial.diffuse.a;
+}

src/java/com/threerings/jme/model/ModelMesh.java

@@ -67,6 +67,7 @@ import com.samskivert.util.PropertiesUtil;
 import com.samskivert.util.StringUtil;
 
 import com.threerings.jme.Log;
+import com.threerings.jme.util.ShaderCache;
 
 /**
  * A {@link TriMesh} with a serialization mechanism tailored to stored models.
@@ -441,6 +442,12 @@ public class ModelMesh extends TriMesh
         }
     }
 
+    // documentation inherited from interface ModelSpatial
+    public void configureShaders (ShaderCache scache)
+    {
+        // no-op
+    }
+
     // documentation inherited from interface ModelSpatial
     public void storeMeshFrame (int frameId, boolean blend)
     {
@@ -603,20 +610,6 @@ public class ModelMesh extends TriMesh
         return astate;
     }
 
-    /**
-     * Concatenates the two provided buffers.
-     */
-    protected static FloatBuffer concatenate (FloatBuffer b1, FloatBuffer b2)
-    {
-        FloatBuffer nb = BufferUtils.createFloatBuffer(b1.capacity() + b2.capacity());
-        b1.clear();
-        nb.put(b1);
-        b2.clear();
-        nb.put(b2);
-        nb.clear();
-        return nb;
-    }
-
     /**
      * Sorts the encoded triangle index/distance pairs in {@link #_tcodes}
      * using a two-pass (16 bit) radix sort (as described by

src/java/com/threerings/jme/model/ModelNode.java

@@ -42,6 +42,7 @@ import com.jme.util.export.OutputCapsule;
 
 import com.threerings.jme.Log;
 import com.threerings.jme.util.JmeUtil;
+import com.threerings.jme.util.ShaderCache;
 
 /**
  * A {@link Node} with a serialization mechanism tailored to stored models.
@@ -259,6 +260,17 @@ public class ModelNode extends Node
         }
     }
 
+    // documentation inherited from interface ModelSpatial
+    public void configureShaders (ShaderCache scache)
+    {
+        for (int ii = 0, nn = getQuantity(); ii < nn; ii++) {
+            Spatial child = getChild(ii);
+            if (child instanceof ModelSpatial) {
+                ((ModelSpatial)child).configureShaders(scache);
+            }
+        }
+    }
+
     // documentation inherited from interface ModelSpatial
     public void storeMeshFrame (int frameId, boolean blend)
     {

src/java/com/threerings/jme/model/ModelSpatial.java

@@ -24,6 +24,8 @@ package com.threerings.jme.model;
 import com.jme.renderer.Renderer;
 import com.jme.scene.Spatial;
 
+import com.threerings.jme.util.ShaderCache;
+
 /**
  * Contains method common to both {@link ModelNode}s and {@link ModelMesh}es.
  */
@@ -56,6 +58,11 @@ public interface ModelSpatial
      */
     public void resolveTextures (TextureProvider tprov);
 
+    /**
+     * Recursively creates or reconfigures any shaders used by the model using the supplied cache.
+     */
+    public void configureShaders (ShaderCache scache);
+
     /**
      * Recursively requests that the current state of all skinned meshes be
      * stored as an animation frame on the next update.

src/java/com/threerings/jme/model/SkinMesh.java

@@ -33,6 +33,8 @@ import java.util.Collections;
 import java.util.HashMap;
 import java.util.HashSet;
 
+import org.lwjgl.opengl.GLContext;
+
 import com.jme.bounding.BoundingVolume;
 import com.jme.math.Matrix4f;
 import com.jme.math.Vector3f;
@@ -42,7 +44,10 @@ import com.jme.scene.TriMesh;
 import com.jme.scene.VBOInfo;
 import com.jme.scene.batch.SharedBatch;
 import com.jme.scene.batch.TriangleBatch;
+import com.jme.scene.state.GLSLShaderObjectsState;
+import com.jme.scene.state.RenderState;
 import com.jme.system.DisplaySystem;
+import com.jme.util.ShaderAttribute;
 import com.jme.util.export.JMEExporter;
 import com.jme.util.export.JMEImporter;
 import com.jme.util.export.InputCapsule;
@@ -52,15 +57,23 @@ import com.jme.util.geom.BufferUtils;
 
 import com.samskivert.util.ArrayUtil;
 import com.samskivert.util.HashIntMap;
+import com.samskivert.util.ListUtil;
 
 import com.threerings.jme.Log;
 import com.threerings.jme.util.JmeUtil;
+import com.threerings.jme.util.ShaderCache;
 
 /**
  * A triangle mesh that deforms according to a bone hierarchy.
  */
 public class SkinMesh extends ModelMesh
 {
+    /** The maximum number of bone matrices that we can use for hardware skinning. */
+    public static final int MAX_SHADER_BONE_COUNT = 32;
+
+    /** The maximum number of bones influencing a single vertex for hardware skinning. */
+    public static final int MAX_SHADER_BONES_PER_VERTEX = 4;
+
     /** Represents the vertex weights of a group of vertices influenced by the
      * same set of bones. */
     public static class WeightGroup
@@ -239,12 +252,26 @@ public class SkinMesh extends ModelMesh
         } else {
             mstore = (SkinMesh)store;
         }
+        GLSLShaderObjectsState sstate = (GLSLShaderObjectsState)getRenderState(
+            RenderState.RS_GLSL_SHADER_OBJECTS);
+        if (sstate == null) {
+            // vertices and normals must be cloned if not using a shader
             properties.removeProperty("vertices");
             properties.removeProperty("normals");
+        }
         properties.removeProperty("displaylistid");
         super.putClone(mstore, properties);
+        if (sstate == null) {
             properties.addProperty("vertices");
             properties.addProperty("normals");
+        } else {
+            // for the shader, we must create a separate instance with different uniforms
+            GLSLShaderObjectsState msstate =
+                DisplaySystem.getDisplaySystem().getRenderer().createGLSLShaderObjectsState();
+            msstate.setProgramID(sstate.getProgramID());
+            msstate.attribs = sstate.attribs;
+            mstore.setRenderState(msstate);
+        }
         properties.addProperty("displaylistid");
         mstore._frames = _frames;
         mstore._useDisplayLists = _useDisplayLists;
@@ -261,8 +288,8 @@ public class SkinMesh extends ModelMesh
         }
         mstore._ovbuf = _ovbuf;
         mstore._onbuf = _onbuf;
-        mstore._vbuf = new float[_vbuf.length];
+        mstore._vbuf = (sstate == null) ? _vbuf : new float[_vbuf.length];
-        mstore._nbuf = new float[_nbuf.length];
+        mstore._nbuf = (sstate == null) ? _nbuf : new float[_nbuf.length];
         return mstore;
     }
 
@@ -323,10 +350,48 @@ public class SkinMesh extends ModelMesh
             vboinfo.setVBOTextureEnabled(true);
             vboinfo.setVBOIndexEnabled(!_translucent);
             setVBOInfo(vboinfo);
+
+            // use VBOs for shader attributes
+            GLSLShaderObjectsState sstate = (GLSLShaderObjectsState)getRenderState(
+                RenderState.RS_GLSL_SHADER_OBJECTS);
+            if (sstate != null) {
+                for (ShaderAttribute attrib : sstate.attribs.values()) {
+                    attrib.useVBO = true;
+                }
+            }
         }
         _useDisplayLists = useDisplayLists && !_translucent;
     }
 
+    @Override // documentation inherited
+    public void configureShaders (ShaderCache scache)
+    {
+        if (_disableShaders || !GLContext.getCapabilities().GL_ARB_vertex_shader ||
+                _bones.length > MAX_SHADER_BONE_COUNT) {
+            return;
+        }
+        int bonesPerVertex = 0;
+        for (WeightGroup group : _weightGroups) {
+            bonesPerVertex = Math.max(group.bones.length, bonesPerVertex);
+        }
+        if (bonesPerVertex > MAX_SHADER_BONES_PER_VERTEX) {
+            return;
+        }
+        GLSLShaderObjectsState sstate = (GLSLShaderObjectsState)getRenderState(
+            RenderState.RS_GLSL_SHADER_OBJECTS);
+        if (sstate == null) {
+            sstate = DisplaySystem.getDisplaySystem().getRenderer().createGLSLShaderObjectsState();
+            setShaderAttributes(sstate, bonesPerVertex);
+            setRenderState(sstate);
+        }
+        if (!scache.configureState(sstate, "media/jme/skin.vert", null,
+            "MAX_BONE_COUNT " + MAX_SHADER_BONE_COUNT, "BONES_PER_VERTEX " + bonesPerVertex)) {
+            clearRenderState(RenderState.RS_GLSL_SHADER_OBJECTS);
+            _disableShaders = true;
+            return;
+        }
+    }
+
     @Override // documentation inherited
     public void storeMeshFrame (int frameId, boolean blend)
     {
@@ -375,6 +440,16 @@ public class SkinMesh extends ModelMesh
             bone.transform.multLocal(bone.invRefTransform);
         }
 
+        // if we're using shaders, initialize the uniform variables with the bone transforms
+        GLSLShaderObjectsState sstate = (GLSLShaderObjectsState)getRenderState(
+            RenderState.RS_GLSL_SHADER_OBJECTS);
+        if (sstate != null) {
+            for (int ii = 0; ii < _bones.length; ii++) {
+                sstate.setUniform("boneTransforms[" + ii + "]", _bones[ii].transform, true);
+            }
+            return;
+        }
+
         // deform the mesh according to the positions of the bones (this code
         // is ugly as sin because it's optimized at a low level)
         Bone[] bones;
@@ -481,6 +556,35 @@ public class SkinMesh extends ModelMesh
         _nbuf = new float[_onbuf.length];
     }
 
+    /**
+     * Initializes the skin shader attributes (bone indices and weights) in the supplied state.
+     */
+    protected void setShaderAttributes (GLSLShaderObjectsState sstate, int bonesPerVertex)
+    {
+        int size = getBatch(0).getVertexCount() * bonesPerVertex;
+        ByteBuffer bibuf = BufferUtils.createByteBuffer(size);
+        FloatBuffer bwbuf = BufferUtils.createFloatBuffer(size);
+
+        for (WeightGroup group : _weightGroups) {
+            byte[] indices = new byte[bonesPerVertex];
+            for (int ii = 0; ii < indices.length; ii++) {
+                indices[ii] = (byte)((ii < group.bones.length) ?
+                    ListUtil.indexOf(_bones, group.bones[ii]) : 0);
+            }
+            for (int ii = 0, widx = 0; ii < group.vertexCount; ii++) {
+                bibuf.put(indices);
+                for (int jj = 0; jj < bonesPerVertex; jj++) {
+                    bwbuf.put((jj < group.bones.length) ? group.weights[widx++] : 0f);
+                }
+            }
+        }
+        bibuf.rewind();
+        bwbuf.rewind();
+
+        sstate.setAttributePointer("boneIndices", bonesPerVertex, false, false, 0, bibuf);
+        sstate.setAttributePointer("boneWeights", bonesPerVertex, false, 0, bwbuf);
+    }
+
     /** A stored frame used for linear blending. */
     protected static class BlendFrame
     {
@@ -535,6 +639,9 @@ public class SkinMesh extends ModelMesh
     /** Whether or not the stored frame id will be used for blending. */
     protected boolean _storeBlend;
 
+    /** Set if we determine that our shaders don't compile to prevent us from trying again. */
+    protected static boolean _disableShaders;
+
     /** A dummy mesh that simply hold transformation values. */
     protected static final TriMesh DUMMY_MESH = new TriMesh();
 

src/java/com/threerings/jme/tools/ModelViewer.java

@@ -114,6 +114,7 @@ import com.threerings.jme.Log;
 import com.threerings.jme.camera.CameraHandler;
 import com.threerings.jme.model.Model;
 import com.threerings.jme.model.TextureProvider;
+import com.threerings.jme.util.ShaderCache;
 import com.threerings.jme.util.SpatialVisitor;
 
 /**
@@ -153,6 +154,7 @@ public class ModelViewer extends JmeCanvasApp
     {
         super(1024, 768);
         _rsrcmgr = new ResourceManager("rsrc");
+        _scache = new ShaderCache(_rsrcmgr);
         _msg = new MessageManager("rsrc.i18n").getBundle("jme.viewer");
         _path = path;
 
@@ -639,6 +641,7 @@ public class ModelViewer extends JmeCanvasApp
         }
         _ctx.getGeometry().attachChild(_model = _omodel = model);
         _model.setAnimationMode(_animMode);
+        _model.configureShaders(_scache);
         _model.lockStaticMeshes(_ctx.getRenderer(), true, true);
 
         // load the model's textures
@@ -814,6 +817,9 @@ public class ModelViewer extends JmeCanvasApp
     /** The resource manager. */
     protected ResourceManager _rsrcmgr;
 
+    /** The shader cache. */
+    protected ShaderCache _scache;
+
     /** The translation bundle. */
     protected MessageBundle _msg;
 

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

@@ -22,9 +22,9 @@
 package com.threerings.jme.util;
 
 import java.io.BufferedReader;
-import java.io.File;
-import java.io.FileReader;
 import java.io.IOException;
+import java.io.InputStream;
+import java.io.InputStreamReader;
 
 import java.nio.IntBuffer;
 
@@ -198,14 +198,16 @@ public class JmeUtil
 
     /**
      * 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>
+     * and returns a GLSL shader state.  One of the supplied streams may be <code>null</code>
      * in order to use the fixed-function pipeline for that part.  The method returns
      * <code>null</code> if the shaders fail to compile (JME will log an error).
      *
      * @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)
+    public static GLSLShaderObjectsState loadShaders (
+        InputStream vert, InputStream frag, String... defs)
+        throws IOException
     {
         GLSLShaderObjectsState sstate =
             DisplaySystem.getDisplaySystem().getRenderer().createGLSLShaderObjectsState();
@@ -223,22 +225,19 @@ public class JmeUtil
     /**
      * Loads an entire source file as a string, prepending the supplied preprocessor definitions.
      */
-    protected static String readSource (File file, String[] defs)
+    protected static String readSource (InputStream in, String[] defs)
+        throws IOException
     {
         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 InputStreamReader(in));
-            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();
     }
 }

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

@@ -0,0 +1,184 @@
+//
+// $Id: ImageCache.java 158 2007-02-24 00:38:17Z mdb $
+//
+// Nenya library - tools for developing networked games
+// Copyright (C) 2002-2007 Three Rings Design, Inc., All Rights Reserved
+// http://www.threerings.net/code/nenya/
+//
+// This library is free software; you can redistribute it and/or modify it
+// under the terms of the GNU Lesser General Public License as published
+// by the Free Software Foundation; either version 2.1 of the License, or
+// (at your option) any later version.
+//
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+// Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public
+// License along with this library; if not, write to the Free Software
+// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+
+package com.threerings.jme.util;
+
+import java.io.IOException;
+
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.HashSet;
+
+import com.jme.scene.state.GLSLShaderObjectsState;
+import com.jme.system.DisplaySystem;
+import com.jme.util.ShaderAttribute;
+import com.jme.util.ShaderUniform;
+
+import com.samskivert.util.ArrayUtil;
+import com.samskivert.util.ObjectUtil;
+
+import com.threerings.resource.ResourceManager;
+
+import static com.threerings.jme.Log.*;
+
+/**
+ * Caches shaders under their names and preprocessor definitions, ensuring that identical shaders
+ * are only compiled once.
+ */
+public class ShaderCache
+{
+    /**
+     * Create a shader cache that will obtain shader source from the supplied resource manager.
+     */
+    public ShaderCache (ResourceManager rsrcmgr)
+    {
+        _rsrcmgr = rsrcmgr;
+    }
+
+    /**
+     * Creates a new shader state with the supplied vertex shader, fragment shader,
+     * and preprocessor definitions.  If a program with the given parameters has already been
+     * compiled, the state will use the program id of the existing shader.
+     *
+     * @return the newly created state, or <code>null</code> if there was an error and the
+     * program could not be compiled.
+     */
+    public GLSLShaderObjectsState createState (String vert, String frag, String... defs)
+    {
+        GLSLShaderObjectsState sstate =
+            DisplaySystem.getDisplaySystem().getRenderer().createGLSLShaderObjectsState();
+        return (configureState(sstate, vert, frag, defs) ? sstate : null);
+    }
+
+    /**
+     * (Re)configures an existing shader state with the supplied parameters.
+     *
+     * @return true if the shader was successfully configured, false if the shader could not
+     * be compiled.
+     */
+    public boolean configureState (
+        GLSLShaderObjectsState sstate, String vert, String frag, String... defs)
+    {
+        return configureState(sstate, vert, frag, defs, null);
+    }
+
+    /**
+     * (Re)configures an existing shader state with the supplied parameters.
+     *
+     * @param ddefs an optional array of derived preprocessor definitions that, unlike the
+     * principal definitions, need not be compared when differentiating between cached shaders.
+     * @return true if the shader was successfully configured, false if the shader could not
+     * be compiled.
+     */
+    public boolean configureState (
+        GLSLShaderObjectsState sstate, String vert, String frag, String[] defs, String[] ddefs)
+    {
+        ShaderKey key = new ShaderKey(vert, frag, defs);
+        Integer programId = _programIds.get(key);
+        if (programId == null) {
+            if (ddefs != null) {
+                defs = ArrayUtil.concatenate(defs, ddefs);
+            }
+            GLSLShaderObjectsState pstate;
+            try {
+                pstate = JmeUtil.loadShaders(
+                    (vert == null) ? null : _rsrcmgr.getResource(vert),
+                    (frag == null) ? null : _rsrcmgr.getResource(frag), defs);
+            } catch (IOException e) {
+                log.warning("Failed to load shaders [vert=" + vert + ", frag=" + frag +
+                    ", error=" + e + "].");
+                return false;
+            }
+            if (pstate == null) {
+                return false;
+            }
+            _programIds.put(key, programId = pstate.getProgramID());
+        }
+        if (sstate.getProgramID() == programId) {
+            return true;
+        }
+        sstate.setProgramID(programId);
+        for (ShaderAttribute attrib : sstate.attribs.values()) {
+            attrib.attributeID = -1;
+        }
+        for (ShaderUniform uniform : sstate.uniforms.values()) {
+            uniform.uniformID = -1;
+        }
+        sstate.setNeedsRefresh(true);
+        return true;
+    }
+
+    /**
+     * Checks whether the specified shader is already loaded.  This is useful in order to avoid
+     * generating complex derived definitions when they won't be needed.
+     */
+    public boolean isLoaded (String vert, String frag, String... defs)
+    {
+        return _programIds.containsKey(new ShaderKey(vert, frag, defs));
+    }
+
+    /** Identifies a cached shader. */
+    protected static class ShaderKey
+    {
+        /** The name of the vertex shader (or <code>null</code> for none). */
+        public String vert;
+
+        /** The name of the fragment shader (or <code>null</code> for none). */
+        public String frag;
+
+        /** The set of preprocessor definitions. */
+        public HashSet<String> defs = new HashSet<String>();
+
+        public ShaderKey (String vert, String frag, String[] defs)
+        {
+            this.vert = vert;
+            this.frag = frag;
+            Collections.addAll(this.defs, defs);
+        }
+
+        @Override // documentation inherited
+        public int hashCode ()
+        {
+            return (vert == null ? 0 : vert.hashCode()) + (frag == null ? 0 : frag.hashCode()) +
+                defs.hashCode();
+        }
+
+        @Override // documentation inherited
+        public boolean equals (Object obj)
+        {
+            ShaderKey okey = (ShaderKey)obj;
+            return ObjectUtil.equals(vert, okey.vert) && ObjectUtil.equals(frag, okey.frag) &&
+                defs.equals(okey.defs);
+        }
+
+        @Override // documentation inherited
+        public String toString ()
+        {
+            return "[vert=" + vert + ", frag=" + frag + ", defs=" + defs + "]";
+        }
+    }
+
+    /** Provides access to shader source. */
+    protected ResourceManager _rsrcmgr;
+
+    /** Maps shader keys to linked program ids. */
+    protected HashMap<ShaderKey, Integer> _programIds = new HashMap<ShaderKey, Integer>();
+}