Creating a height map from an image

In this recipe, we will learn how to create a point cloud based on an image selected by the user. We will create a grid of points where each point will correspond to a pixel. The x and y coordinates of each point will be equal to the pixel's position on the image, and the z coordinate will be calculated based on its color.

Getting ready

Include the necessary files to work with OpenGL, image surfaces, VBO meshes, and loading images.

Add the following code to the top of the source file:

#include "cinder/gl/gl.h"
#include "cinder/Surface.h"
#include "cinder/gl/Vbo.h"
#include "cinder/MayaCamUI.h"
#include "cinder/ImageIo.h"

Also, add the following using statements:

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

How to do it…

We will learn how to read pixel values from an image and create a point cloud.

1. Declare ci::Surface32f to store the image pixels, ci::gl::VboMesh that we will use as the point cloud, and ci::MayaCamUI for easy rotation of our...