checkpoint
[anneal.git] / src / edu / berkeley / qfat / MeshViewer.java
index 2b6ba8e..97a31f8 100644 (file)
@@ -11,143 +11,33 @@ import java.util.*;
 import edu.berkeley.qfat.geom.*;
 import edu.berkeley.qfat.geom.Point;
 
-public class MeshViewer implements GLEventListener, MouseListener, MouseMotionListener, KeyListener, MouseWheelListener  {
-
-    public boolean force = false;
-    public Mesh tile = new Mesh(false);
-    public Mesh goal = new Mesh(false);
-    public Matrix[] transforms;
-    public Mesh.Vertex[] points;
-
-    public int whichNeighbor = 1;
-
-    public double temp;
-    public boolean tileon = true;
-    public boolean tilemeshon = false;
-    public boolean goalon = true;
-    public boolean anneal = false;
-    public boolean hillclimb = false;
-    public boolean neighbors = false;
-    public boolean neighborsWire = false;
-    public boolean neighborsWireOne = false;
-    public boolean errorNormals = false;
-
-    public int breaks = 0;
-    boolean alt = false;
-    boolean shift = false;
-    boolean control = false;
+public class MeshViewer extends JPanel implements GLEventListener, MouseListener, MouseMotionListener, KeyListener, MouseWheelListener {
 
-    public Point getMouse() {
-        return new Point(mousex, glcanvas.getHeight()-mousey, 0);
-    }
+    private float tz = 0;
+    private float anglex = 0;
+    private float angley = 0;
 
-    public void mouseWheelMoved(MouseWheelEvent e) {
-        tz -= e.getWheelRotation();
-    }
+    private Mesh.Vertex closest = null;
+    private int         mousex;
+    private int         mousey;
+    private Matrix      projection = null;
+    private Point       clickPoint = null;
+    private GLCanvas    glcanvas;
+    private boolean     updateVisibilities = false;
+    private boolean     mouseInside = false;
 
-    public void keyTyped(KeyEvent e)  { }
-    public void keyPressed(KeyEvent e)  {
-        switch(e.getKeyCode()) {
-            case KeyEvent.VK_CONTROL: control = true; break;
-            case KeyEvent.VK_ALT: alt = true; break;
-            case KeyEvent.VK_SHIFT: shift = true; break;
-            case KeyEvent.VK_SPACE: breaks++; force = true; break;
-            case KeyEvent.VK_UP: temp = temp * 2; break;
-            case KeyEvent.VK_ENTER: temp = 10; break;
-            case KeyEvent.VK_LEFT: whichNeighbor--; break;
-            case KeyEvent.VK_RIGHT: whichNeighbor++; break;
-            case KeyEvent.VK_D: dump(); break;
-            case KeyEvent.VK_E: errorNormals = !errorNormals; break;
-            case KeyEvent.VK_A: hillclimb = false; anneal = !anneal; break;
-            case KeyEvent.VK_H: anneal = true; hillclimb = !hillclimb; break;
-            case KeyEvent.VK_N: neighbors = !neighbors; break;
-            case KeyEvent.VK_T: tileon = !tileon; break;
-            case KeyEvent.VK_G: goalon = !goalon; break;
-            case KeyEvent.VK_M: tilemeshon = !tilemeshon; break;
-        }
-    }
-    public synchronized void dump() {
-        try {
-        PrintWriter pw = new PrintWriter(new OutputStreamWriter(new FileOutputStream("dump.stl")));
-        pw.println("solid dump");
-        for(Mesh.T t : tile) {
-            Vec normal = t.norm();
-            pw.println("facet normal " + normal.x + " " + normal.y + " " + normal.z);
-            pw.println("  outer loop");
-            for(Mesh.Vertex v : new Mesh.Vertex[] { t.v1(), t.v2(), t.v3() }) {
-                pw.println("    vertex " + v.p.x + " " + v.p.y + " " + v.p.z);
-            }
-            pw.println("  endloop");
-            pw.println("endfacet");
-        }
-        pw.println("endsolid dump");
-        pw.flush();
-        pw.close();
-        } catch (Exception e) { throw new RuntimeException(e); }
-    }
-    public void keyReleased(KeyEvent e) {
-        switch(e.getKeyCode()) {
-            case KeyEvent.VK_CONTROL: control = false; break;
-            case KeyEvent.VK_ALT: alt = false; break;
-            case KeyEvent.VK_SHIFT: shift = false; break;
-        }
-    }
+    private HashSet<Mesh> meshes = new HashSet<Mesh>();
 
-    public void mouseClicked(MouseEvent e) { }
-    public void mouseEntered(MouseEvent e) { }
-    public void mouseExited(MouseEvent e) { }
-    public void mousePressed(MouseEvent e) {
-        clickPoint = getMouse();
-        clickClosest = closest == null ? null : closest.getPoint();
-    }
-    public void mouseReleased(MouseEvent e) {
-        clickPoint = null;
-        clickClosest = null;
-    }
+    public synchronized void addMesh(Mesh m) { meshes.add(m); }
+    public synchronized void removeMesh(Mesh m) { meshes.remove(m); }
 
-    Point clickPoint = null;
-    Point clickClosest = null;
+    public void reshape(GLAutoDrawable drawable, int x, int y, int width, int height) { }
+    public void displayChanged(GLAutoDrawable drawable, boolean modeChanged, boolean deviceChanged) { }
 
-    int mousex;
-    int mousey;
-    public void mouseMoved(MouseEvent e) {
-        mousex = e.getX();
-        mousey = e.getY();
-    }
+    public void addKeyListener(KeyListener kl) { glcanvas.addKeyListener(kl); }
 
-    float tx = 0;
-    float ty = 0;
-    float tz = 0;
-    float anglex = 0;
-    float angley = 0;
-    public void mouseDragged(MouseEvent e) {
-        if (shift) {
-            /*
-            tx += (mousex - e.getX())/(float)20;
-            ty += (mousey - e.getY())/(float)20;
-            */
-            if (closest != null && lastGL != null && projection != null && clickClosest != null) {
-                synchronized(safeTriangles) {
-                    Vec d1 = projection.inverse().times(getMouse()).minus(projection.inverse().times(clickPoint));
-                    Vec delta = d1.plus(clickClosest).minus(closest.getPoint());
-                    //System.out.println(delta + " " + closest.getPoint());
-                    System.out.println(getMouse().minus(clickPoint));
-                    closest.move(Matrix.translate(delta), true);
-                }
-            }
-        } else {
-            anglex -= mousex - e.getX();
-            angley += mousey - e.getY();
-        }
-        mousex = e.getX();
-        mousey = e.getY();
-    }
-
-    /**
-     * Take care of initialization here.
-     */
-    public void init(GLAutoDrawable gld) {
-        GL gl = gld.getGL();
+    public synchronized void init(GLAutoDrawable gld) {
+        GL gl = glcanvas.getGL();//gld.getGL();
         gl.glClearColor(0.0f, 0.0f, 0.0f, 1.0f);
         gl.glViewport(0, 0, 500, 300);
         gl.glEnable(GL.GL_DEPTH_TEST);
@@ -172,290 +62,184 @@ public class MeshViewer implements GLEventListener, MouseListener, MouseMotionLi
         gl.glLightfv(GL.GL_LIGHT5, GL.GL_POSITION, new float[] { 10.0f, -10.0f,  -10.0f, 0.0f }, 0);
         gl.glEnable(GL.GL_LIGHTING);
         gl.glEnable(GL.GL_LIGHT0);
-        /*
-        gl.glEnable(GL.GL_LIGHT1);
-        gl.glEnable(GL.GL_LIGHT2);
-        gl.glEnable(GL.GL_LIGHT3);
-        gl.glEnable(GL.GL_LIGHT4);
-        gl.glEnable(GL.GL_LIGHT5);
-        */
+
         gl.glColorMaterial(GL.GL_FRONT_AND_BACK, GL.GL_AMBIENT_AND_DIFFUSE);
         gl.glEnable(GL.GL_COLOR_MATERIAL);
 
         display(gld);
+
+        // hack to get around Mac OS bug
+        IntBuffer buf = ByteBuffer.allocateDirect(9*4*4).order(ByteOrder.nativeOrder()).asIntBuffer();
+        gl.glReadPixels(0,0, 1, 1, gl.GL_RGB, gl.GL_UNSIGNED_BYTE, buf);
     }
 
-    private GL lastGL = null;
+    public synchronized final void display(GLAutoDrawable drawable) {
+        glcanvas.setSize(glcanvas.getParent().getWidth(), glcanvas.getParent().getHeight());
 
-    public int temps;
-    public int accepts;
-    public    int vertss;
-    public void reshape(GLAutoDrawable drawable, int x, int y, int width, int height) { }
-    public void displayChanged(GLAutoDrawable drawable, boolean modeChanged, boolean deviceChanged) { }
-    public void display(GLAutoDrawable drawable) {
-
-        if (transforms==null) return;
-
-
-        glcanvas.setSize(f.getWidth(), f.getHeight() - 100);
-        Graphics2D g = (Graphics2D)f.getGraphics();
-        g.setColor(Color.black);
-        g.fillRect(0, f.getHeight()-100, f.getWidth(), f.getHeight());
-        g.setColor(Color.red);
-        int top = f.getHeight()-70;
-        g.drawString("temperature: "+temps, 10, 30+top);
-        g.drawString("acceptance: "+accepts, 10, 50+top);
-        g.drawString("vertices: "+vertss, 10, 70+top);
-        g.fillRect(140, 25+top, temps, 10);
-        g.fillRect(140, 45+top, accepts, 10);
-        g.fillRect(140, 65+top, vertss, 10);
-
-        GL gl = drawable.getGL();
-        lastGL = gl;
+        GL gl = glcanvas.getGL();//drawable.getGL();
         GLU glu = new GLU();
+
+        if (!mouseInside) gl.glClearColor(0.1f, 0.1f, 0.1f, 1.0f);
+        else gl.glClearColor(0.0f, 0.0f, 0.0f, 1.0f);
+
         gl.glClear(GL.GL_COLOR_BUFFER_BIT | GL.GL_DEPTH_BUFFER_BIT);
         gl.glPointSize(5.0f);
         gl.glLoadIdentity();
         glu.gluPerspective(50, ((float)drawable.getWidth())/drawable.getHeight(), 0.5, 10);
+
         glu.gluLookAt(0, 0, -((tz/10)-1), 0, 0, 0, 0, 1, 0);
         gl.glRotatef(anglex/3, 0, 1, 0);
         gl.glRotatef(-(angley/3), 1, 0, 0);
 
-
-        gl.glDisable(GL.GL_LIGHTING);
-        gl.glColor4f(1, 0, 0, 1);
-        gl.glBegin(GL.GL_LINES);
-        gl.glVertex3f(0,0,0);
-        gl.glVertex3f(.3f,0,0);
-        gl.glEnd();
-        gl.glColor4f(0, 1, 0, 1);
-        gl.glBegin(GL.GL_LINES);
-        gl.glVertex3f(0,0,0);
-        gl.glVertex3f(0,.3f,0);
-        gl.glEnd();
-        gl.glColor4f(0, 0, 1, 1);
-        gl.glBegin(GL.GL_LINES);
-        gl.glVertex3f(0,0,0);
-        gl.glVertex3f(0,0,.3f);
-        gl.glEnd();
         gl.glEnable(GL.GL_LIGHTING);
+        gl.glShadeModel(GL.GL_SMOOTH);
+        for(Mesh mesh : meshes)
+            mesh.render(gl, Matrix.ONE);
 
-
-        gl.glBegin(GL.GL_TRIANGLES);
-        if (tileon)
-            draw(gl, true, safeTriangles);
-        if (tilemeshon)
-            draw(gl, false, safeTriangles);
-        gl.glEnd();
-
-        //draw(gl, false, tile);
-
-        gl.glBegin(GL.GL_TRIANGLES);
-        gl.glColor4f((float)0.5, (float)0.5, (float)0.5, (float)0.8);
-        if (goalon)
-            draw(gl, false, goal);
-        gl.glEnd();
-
-
-        int i = 0;
-        //gl.glDisable(GL.GL_DEPTH_TEST);
-        gl.glColor4f(1,1,1,1);
-        for(Matrix m : transforms) {
-            /*
-              gl.glColor4f(0, 1, 1, 1);
-              gl.glBegin(GL.GL_LINES);
-              new Point(0,0,0).glVertex(gl);
-              new Point(0,0,0).plus(m.getTranslationalComponent()).glVertex(gl);
-              gl.glEnd();
-              gl.glEnable(GL.GL_LIGHTING);
-            */
-            //if (v1.z==0 && v1.y==0) continue;
-            i++;
-            if (neighborsWireOne && i!=whichNeighbor) continue;
-            //if (i>4) continue;
-            /*
-            Point p = new Point(0, 0, 0).times(m);
-            Vec v = new Vec(p.x, p.y, p.z);
-            v = v.times((float)1.04);
-            gl.glTranslatef(v.x, v.y, v.z);
-            */
-            if (neighbors) draw(gl, true, safeTriangles, m);
-            else if (neighborsWire || neighborsWireOne) draw(gl, false, safeTriangles, m);
-            /*
-            gl.glTranslatef(-v.x, -v.y, -v.z);
-            */
-        }
-        //gl.glEnable(GL.GL_DEPTH_TEST);
-
-        gl.glDisable(GL.GL_LIGHTING);
-        gl.glShadeModel(GL.GL_FLAT);
+        // highlight the point closest to the mouse; we do this here to avoid flicker
         if (closest != null) {
+            gl.glDisable(GL.GL_LIGHTING);
+            gl.glShadeModel(GL.GL_FLAT);
             gl.glColor3f(1,1,1);
             gl.glBegin(gl.GL_POINTS);
             closest.getPoint().glVertex(gl);
             gl.glEnd();
-            /*
-            Mesh.Vertex v2 = closest.hack(gl, getMouse());
-            gl.glBegin(GL.GL_LINES);        
-            closest.getPoint().glVertex(gl);                                                                                                  
-            if (v2 != null) v2.getPoint().glVertex(gl);
-            gl.glEnd();
-            */
         }
 
+        projection = Matrix.getProjectionMatrix(gl);
+
+        if (updateVisibilities) {
+            updateVisibilities = false;
+            // update vertex visibilities
+            updateVisibility(gl);
+            
+            //Matrix projection = Matrix.getProjectionMatrix(gl);
+            double dist = Double.MAX_VALUE;
+            closest = null;
+            for(Mesh mesh : meshes)
+                if (mesh.option_selectable)
+                    for(Mesh.Vertex v : mesh.vertices()) {
+                        if (!v.visible) continue;
+                        Point p = projection.times(v.getPoint());
+                        int x = (int)p.x;
+                        int y = (int)p.y;
+                        int mousex = (int)getMouse().x;
+                        int mousey = (int)getMouse().y;
+                        if (closest==null || (x-mousex)*(x-mousex)+(y-mousey)*(y-mousey) < dist) {
+                            dist = (x-mousex)*(x-mousex)+(y-mousey)*(y-mousey);
+                            closest = v;
+                        }
+                    }
+        }
+    }
+
+    protected synchronized void updateVisibility(GL gl) {
+        IntBuffer buf = ByteBuffer.allocateDirect(9*4*4).order(ByteOrder.nativeOrder()).asIntBuffer();
         gl.glFlush();
         gl.glDrawBuffer(GL.GL_BACK);
-        gl.glReadBuffer( GL.GL_BACK );
-        gl.glPixelStorei( GL.GL_PACK_ALIGNMENT, 1);
+        gl.glReadBuffer(GL.GL_BACK);
+        gl.glPixelStorei(GL.GL_PACK_ALIGNMENT, 1);
         gl.glFlush();
         gl.glDisable(GL.GL_LIGHTING);
         gl.glShadeModel(GL.GL_FLAT);
-
-        IntBuffer buf = ByteBuffer.allocateDirect(9*4*4).order(ByteOrder.nativeOrder()).asIntBuffer();
         gl.glColor3f(0,0,0);
         gl.glClear(GL.GL_COLOR_BUFFER_BIT | GL.GL_DEPTH_BUFFER_BIT);
-        double dist = Double.MAX_VALUE;
-        if (clickPoint==null) closest = null;
-        projection = Matrix.getProjectionMatrix(gl);
-        synchronized(safeTriangles) {
-            for(Mesh.T t : safeTriangles)
-                t.glTriangle(gl, null);
-            for(Mesh.Vertex v : tile.vertices()) {
-                Point p = v.getPoint();
-                gl.glColor3f(1,1,1);
-                gl.glBegin(gl.GL_POINTS);
-                p.glVertex(gl);
-                gl.glEnd();
-                gl.glFlush();
-
-                Point projected = projection.times(p);
-                int x = (int)projected.x;
-                int y = (int)projected.y;
-                gl.glReadPixels(x-1, y-1, 3, 3, gl.GL_RGB, gl.GL_UNSIGNED_BYTE, buf);
-
-                boolean vis = false;
-                for(int j=0; j<9*4; j++) vis |= buf.get(j)!=0;
-                v.visible = vis;
-                if (vis) {
-                    gl.glColor3f(0,0,0);
+        for(Mesh mesh : meshes) mesh.render(gl, Matrix.ONE);
+        for(Mesh mesh : meshes)
+            if (mesh.option_selectable)
+                for(Mesh.Vertex v : mesh.vertices()) {
+                    Point p = v.getPoint();
+                    gl.glColor3f(1,1,1);
                     gl.glBegin(gl.GL_POINTS);
                     p.glVertex(gl);
                     gl.glEnd();
-                    y = glcanvas.getHeight()-y;
-                    if (clickPoint==null) {
-                        if (closest==null || (x-mousex)*(x-mousex)+(y-mousey)*(y-mousey) < dist) {
-                            dist = (x-mousex)*(x-mousex)+(y-mousey)*(y-mousey);
-                            closest = v;
-                        }
+                    gl.glFlush();
+                    
+                    Point projected = projection.times(p);
+                    gl.glReadPixels((int)projected.x-1, (int)projected.y-1, 3, 3, gl.GL_RGB, gl.GL_UNSIGNED_BYTE, buf);
+                    
+                    boolean vis = false;
+                    for(int j=0; j<9*4; j++) vis |= buf.get(j)!=0;
+                    v.visible = vis;
+                    if (vis) {
+                        gl.glColor3f(0,0,0);
+                        gl.glBegin(gl.GL_POINTS);
+                        p.glVertex(gl);
+                        gl.glEnd();
                     }
                 }
-            }
-        }
         gl.glShadeModel(GL.GL_SMOOTH);
         gl.glEnable(GL.GL_LIGHTING);
         gl.glDrawBuffer(GL.GL_FRONT);
     }
-    Mesh.Vertex closest = null;
-    Matrix projection = null;
-
-    protected HashSet<Mesh.T> safeTriangles = new HashSet<Mesh.T>();
-
-    private void draw(GL gl, boolean triangles, Iterable<Mesh.T> tris) { draw(gl, triangles, tris, Matrix.ONE); }
-    private void draw(GL gl, boolean triangles, Iterable<Mesh.T> tris, Matrix m) {
-        float red = 0.0f;
-        float green = 0.0f;
-        float blue = 0.0f;
-        synchronized(safeTriangles) {
-        for(Mesh.T t : tris) {
-            if (red < 0.15) red = 1.0f;
-            if (green < 0.15) green = 1.0f;
-            if (blue < 0.15) blue = 1.0f;
-            red -= .09f;
-            green -= .12f;
-            blue -= .15f;
-
-            /*
-            if (triangles) switch(t.color) {
-                case 0: gl.glColor4f((float)0.25, (float)0.25, (float)0.75, (float)0.3); break;
-                case 1: gl.glColor4f((float)0.25, (float)0.75, (float)0.25, (float)0.3); break;
-                case 2: gl.glColor4f((float)0.75, (float)0.25, (float)0.25, (float)0.3); break;
-                case 3: gl.glColor4f((float)0.50, (float)0.50, (float)0.50, (float)0.3); break;
-                case 4: gl.glColor4f((float)0.25, (float)0.75, (float)0.75, (float)0.3); break;
-                case 5: gl.glColor4f((float)0.25, (float)0.75, (float)0.75, (float)0.3); break;
-                case 6: gl.glColor4f((float)0.75, (float)0.25, (float)0.75, (float)0.3); break;
-            }
-            */
-            
-            gl.glColor4f((float)(0.25+(0.05*t.color)),
-                         (float)(0.25+(0.05*t.color)),
-                         (float)(0.75+(0.05*t.color)),
-                         (float)0.3); 
-            //if (t.v1().visible && t.v2().visible && t.v3().visible) continue;
-
-            /*
-            if (t.e1().pair.t==null) gl.glColor4f((float)0.25, (float)0.25, (float)0.75, (float)0.3);
-            else if (t.e2().pair.t==null) gl.glColor4f((float)0.25, (float)0.25, (float)0.75, (float)0.3);
-            else if (t.e3().pair.t==null) gl.glColor4f((float)0.25, (float)0.25, (float)0.75, (float)0.3);
-            else  gl.glColor4f((float)0.75, (float)0.25, (float)0.25, (float)0.3);
-            */
-            //gl.glBegin(GL.GL_LINES);
-
-            if (triangles) {
-                t.glTriangle(gl, m);
-            } else {
-                gl.glDisable(GL.GL_LIGHTING);
-                gl.glBegin(GL.GL_LINES);
-                gl.glColor3f(1, 1, 1);
-                m.times(t.e1().p1.goodp).glVertex(gl);
-                m.times(t.e1().p2.goodp).glVertex(gl);
-                m.times(t.e2().p1.goodp).glVertex(gl);
-                m.times(t.e2().p2.goodp).glVertex(gl);
-                m.times(t.e3().p1.goodp).glVertex(gl);
-                m.times(t.e3().p2.goodp).glVertex(gl);
-                gl.glEnd();
-                gl.glEnable(GL.GL_LIGHTING);
-            }
 
-            Point centroid = t.centroid();
-            gl.glBegin(GL.GL_LINES);
-            gl.glColor3f(1, 1, 1);
-
-            if (triangles && errorNormals)
-                for(Mesh.Vertex p : new Mesh.Vertex[] { t.v1(), t.v2(), t.v3() }) {
-                    if (p.ok) {
-                        //gl.glDisable(GL.GL_LIGHTING);
-                        gl.glBegin(GL.GL_LINES);
-                        gl.glColor3f(1, 1, 1);
-                        p.p.glVertex(gl);
-                        p.p.plus(p.norm().times((float)p.error()*10)).glVertex(gl);
-                        //if (p.nearest_in_other_mesh != null) p.nearest_in_other_mesh.p.glVertex(gl);
-                        //tile.nearest(p).centroid().glVertex(gl);
-                        gl.glEnd();
-                        //gl.glEnable(GL.GL_LIGHTING);
-                    }
+    /** return the position of the mouse as a point in window-space */
+    public Point getMouse() {
+        return new Point(mousex, glcanvas.getHeight()-mousey, 0);
+    }
+
+    /** return the position where the mouse button was pressed, or null if it is not currently pressed */
+    public Point getMouseClick() {
+        return clickPoint;
+    }
+
+    public void mouseWheelMoved(MouseWheelEvent e) {
+        tz -= e.getWheelRotation();
+    }
+
+    public void keyTyped(KeyEvent e)  { }
+    public void keyPressed(KeyEvent e)  { }
+    public void keyReleased(KeyEvent e) { }
+
+    public void mouseClicked(MouseEvent e) { }
+    public void mouseEntered(MouseEvent e) { mouseInside = true; }
+    public void mouseExited(MouseEvent e) { mouseInside = false; }
+    public void mousePressed(MouseEvent e) {
+        clickPoint = getMouse();
+    }
+
+    public void mouseReleased(MouseEvent e) {
+        clickPoint = null;
+    }
+
+    public void mouseMoved(MouseEvent e) {
+        mousex = e.getX();
+        mousey = e.getY();
+        if ((e.getModifiersEx() & MouseEvent.SHIFT_DOWN_MASK) != 0)
+            updateVisibilities = true;
+    }
+
+    public void mouseDragged(MouseEvent e) {
+        if ((e.getModifiersEx() & MouseEvent.SHIFT_DOWN_MASK) != 0) {
+            if (closest != null && projection != null) {
+                synchronized(this) {
+                    Point clickClosest = closest == null ? null : closest.getPoint();
+                    Vec d1 = projection.inverse().times(getMouse()).minus(projection.inverse().times(clickPoint));
+                    Vec delta = d1.plus(clickClosest).minus(closest.getPoint());
+                    closest.move(delta, false);
                 }
-            gl.glEnd();
-            
-        }
+            }
+        } else {
+            anglex -= mousex - e.getX();
+            angley += mousey - e.getY();
         }
+        mousex = e.getX();
+        mousey = e.getY();
     }
 
-    private JFrame f;
-    private GLCanvas glcanvas;
-    public MeshViewer(JFrame f) {
-        this.f = f;
-
-        GLCapabilities glcaps = new GLCapabilities();
+    public MeshViewer() {
         glcanvas = new GLCanvas();
         glcanvas.addGLEventListener(this);
-        f.add(glcanvas, BorderLayout.CENTER);
-
+        setLayout(new BorderLayout());
+        this.add(glcanvas, BorderLayout.CENTER);
         glcanvas.addMouseListener(this);
         glcanvas.addMouseMotionListener(this);
         glcanvas.addMouseWheelListener(this);
         glcanvas.addKeyListener(this);
     }
+
     public void repaint() {
-        glcanvas.repaint();
+        if (glcanvas != null) glcanvas.repaint();
     }
+
 }
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