ofxRay

Introduction

A lightweight set of tools for intersection testings (e.g. does a ray intersect a plane).

Note

The current code in this repository is designed for openFrameworks 0.10.0. If you are looking for a version of ofxRay which is compatible with previous versions of openFrameworks, please check https://github.com/elliotwoods/ofxRay/tree/0.9.8 .

Objects

ofxRay::Ray

A _Ray_ is defined by the starting point s and the transmission vector t . Check equation (5) at http://mathworld.wolfram.com/Line.html

We define a ray as an infinite line (continuing infinitely forwards and backwards along the line t and - t starting at s .

The line is defined by points s + u t , where {-inf < _u_ < +inf}.

A _Line segment_ is a line which has finite length. We denote a line segment as a ofRay between s and t where infinite is set to _false_ , i.e. a _Line segment_ is a finite section along a ray

ofxRay::Plane

A _Plane_ is defined by a position on the plane c and a normal vector n .

We can also define the plane using the notation _a_ x + _b_ y + _c_ z + _d_ = 0 (by using the appropriate constructor).

For a non-infinite plane, we define the bounds of the _Plane segment_ with the 2D vector bounds, and the up vector up. We presume that the up vector and n vectors are perpendicular.

ofxRay::Projector

A _Projector_ is defined by projection matrix and its pose (defined by ofNode which it inherits from).

We can use a projector to preview a projector or camera in a scene, and to generate pixel _ofRay_s.

ofxRay::Camera

A _Camera_ is defined the same as a _Projector_, but has distortion coefficients also.

ofxRay::Base

All objects within ofxRay inherit from ofxRay::Base.

Authors

Elliot Woods (main author)

• Roy Macdonald (improvements and glm refactoring)