Picking in 3D

In this recipe, we will calculate the intersection of the mouse cursor with a 3D model.

Getting ready

Include the necessary files to draw using OpenGL, use textures and load images, load 3D models, define OpenGL lights and materials, and use Cinder's Maya camera.

#include "cinder/gl/gl.h"
#include "cinder/gl/Texture.h"
#include "cinder/gl/Light.h"
#include "cinder/gl/Material.h"
#include "cinder/TriMesh.h"
#include "cinder/ImageIo.h"
#include "cinder/MayaCamUI.h"

Also, add the following using statements:

using namespace ci;
using namespace ci::app;
using namespace std;

We will use a 3D model, so place a file and its texture in the assets folder. For this example, we will be using a mesh file named ducky.msh and a texture named ducky.png.

How to do it…

1. We will use the ci::CameraPersp and ci::Ray classes to convert the mouse coordinates to our rotated 3D scene and calculate the intersection with a 3D model.

2. Declare the members to define the 3D model and its intersection with the mouse...