timmy_b

I am relatively inexperienced Java person, I usually work with Processing and avoid Eclipse, but I have created a few max externals previously. I haven't, however, created any mxj objects that use external libraries.

I thought I followed the process correctly. I believe I have imported the libraries correctly into my java project in eclipse (toxi libs). I am not getting any errors, put it that way, but when I try and run the object in max I get this error.

java.lang.NoClassDefFoundError: toxi/physics2d/behaviors/ParticleBehavior2D

I believe this is a class path thing? Perhaps max doesn't know where to find the verletphysics.jar ?

My class is below. Essentially I am wanting to use toxi physics to augment imput - at the present it is obviously not doing that - I was just testing the concept , which didn't work!! The class is based on Toxi's example.

public class toxiPart extends MaxObject {

    AttractionBehavior mouseAttractor;

         physics = new VerletPhysics2D();

         physics.setWorldBounds(new Rect(0, 0, 200, 200));

         mousePos = new Vec2D(100, 100);

         // create a new positive attraction force field around the mouse position (radius=250px)

         mouseAttractor = new AttractionBehavior(mousePos, 1000, 0.9f);

         physics.addBehavior(mouseAttractor);

         declareInlets(new int[]{ DataTypes.ALL, DataTypes.ALL});

     declareOutlets(new int[]{ DataTypes.ALL, DataTypes.ALL});

         VerletParticle2D p = new VerletParticle2D(Vec2D.randomVector().scale(5).addSelf(200 / 2, 0));

         // add a negative attraction force field around the new particle

         //physics.addBehavior(new AttractionBehavior(p, 20, -1.2f, 0.01f));

        if (physics.particles.size() < NUM_PARTICLES) {

        mousePos.set((float)Math.random()*200, (float)Math.random()*200);

         for (VerletParticle2D p : physics.particles) {

I thought I followed the process correctly.  I believe I have imported the libraries correctly into my java project in eclipse (toxi libs).  I am not getting any errors, put it that way, but when I try and run the object in max I get this error.

I believe this is a class path thing?  Perhaps max doesn't know where to find the verletphysics.jar ?

My class is below.  Essentially I am wanting to use toxi physics to augment imput - at the present it is obviously not doing that - I was just testing the concept , which didn't work!!  The class is based on Toxi's example.  

import toxi.geom.*;
import toxi.physics2d.*;
import toxi.physics2d.behaviors.*;

	VerletPhysics2D physics;
	AttractionBehavior mouseAttractor;
	Vec2D mousePos;

		 physics = new VerletPhysics2D();
		  physics.setDrag(0.05f);
		  physics.setWorldBounds(new Rect(0, 0, 200, 200));

		  //set attractor
		  mousePos = new Vec2D(100, 100);
		  // create a new positive attraction force field around the mouse position (radius=250px)
		  mouseAttractor = new AttractionBehavior(mousePos, 1000, 0.9f);
		  physics.addBehavior(mouseAttractor);

		  declareInlets(new int[]{ DataTypes.ALL, DataTypes.ALL});
	        declareOutlets(new int[]{ DataTypes.ALL, DataTypes.ALL});

	void addParticle() {
		  VerletParticle2D p = new VerletParticle2D(Vec2D.randomVector().scale(5).addSelf(200 / 2, 0));
		  physics.addParticle(p);
		  // add a negative attraction force field around the new particle
		  //physics.addBehavior(new AttractionBehavior(p, 20, -1.2f, 0.01f));
		}

		if (physics.particles.size() < NUM_PARTICLES) {
		    addParticle();
		  }

		mousePos.set((float)Math.random()*200, (float)Math.random()*200);
		  physics.update();

		  for (VerletParticle2D p : physics.particles) {
		    outlet(0,p.x);
		    outlet(1,p.y);
		  }

understanding-classpaths-when-creating-externals-in-eclipse-w-toxi-libs

You need to place verletphysics.jar into the Max classpath. On the Mac I believe this would be anywhere in the Max path - I put mine in "/Applications/Max 6.1/Cycling '74/java/lib".

You need to place verletphysics.jar into the Max classpath.  On the Mac I believe this would be anywhere in the Max path -  I put mine in "/Applications/Max 6.1/Cycling '74/java/lib".


Also if you want to create easily redistributable library of Java objects, your can build a jar-file with all dependencies in it and place this file to the "Cycling '74/java/lib" directory.

Awesome, thanks for the replies - will get onto that tonight!

Understanding Classpaths when creating externals in Eclipse w toxi Libs