Integrating JPCT-AE with Vuforia

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Qualcomm's Vuforia engine is one of the most powerfull Augmented Reality engines out there. It's integration with jPCT-AE is a wonderful combination for easily creating spectacular AR scenes with your Android device.

The integration process, though, might get a little messy and confusing for someone without much experience with matrices or scene graphs. This guide will try to detail how to achieve a quick integration in a step-by-step fashion.

First of all, you should follow Qualcomm’s Getting Started guide to set up your environment to use Vuforia.

You should get to the point where you have run the ImageTargets demo app, since we will start from that sample.

Setting up the environment

Open the ImageTargets demo project on Eclipse. Right click on the project, then select properties. Go to Java Build Path, then Libraries and add the jpct-ae.jar library using the Add External JARs… option.

Now we can start getting jpct-ae code into our app.

jPCT-AE and Vuforia working together

Now we can start getting jpct-ae code into our app.

First, we will make jpct-ae and vuforia’s native code share the same GLsurface. For that, first open under the ImageTargets sample app (package com.qualcomm.QCARSamples.ImageTargets).

This is the OpenGL renderer, and thus it’s where our jPCT code should be injected in. We will start by taking JPCT-AE Hello World sample app into this renderer. First, create a constructor for ImageTargetsRenderer. This is for the Activity reference to be passed on to our renderer, instead of explicitly setting the attribute, as Qualcomm’s demo does. We will also init our scene here.

public ImageTargetsRenderer(ImageTargets activity){
    	        this.mActivity = activity;
                world = new World();
		world.setAmbientLight(20, 20, 20);

		sun = new Light(world);
		sun.setIntensity(250, 250, 250);

		// Create a texture out of the icon...:-)
		Texture texture = new Texture(BitmapHelper.rescale(BitmapHelper.convert(mActivity.getResources().getDrawable(R.drawable.ic_launcher)), 64, 64));
		TextureManager.getInstance().addTexture("texture", texture);

		cube = Primitives.getCube(10);


		Camera cam = world.getCamera();
		cam.moveCamera(Camera.CAMERA_MOVEOUT, 50);

		SimpleVector sv = new SimpleVector();
		sv.y -= 100;
		sv.z -= 100;


As you can see, I just copied and pasted the code in the Hello World demo (and changed the icon reference). Now go to, then change the initialization of ImageTargetsRenderer to include the activity in the constructor, and remove the line setting this immediately after.

Then go back to ImageTargetsRenderer, into the onSurfaceChanged method. This method is called whenever our surface changes size. We should put jpct-ae framebuffer initialization code here, right from the Hello World demo.