ofVec3ffile

ofVec3fclass

ofVec3f is a class for storing a three dimensional vector.

Moving through space requires knowledge of where things are and where they are going. Vector Maths is the class of mathematics that gives us control over these things in space, allowing for elegant and intuitive descriptions of complex structures and movement. Vectors are at the heart of animations, particle systems, and 2D and 3D graphics.

Vectors in mathematics in general are entities with magnitude (also called length) and direction. A vector whose magnitude is 1 (ie a vector that is normalized) is called a unit vector. Unit vectors are very handy for storing directions as they can be easily scaled up (or down) to represent motion in a particular direction with a particular length.

You will also see the term 'vector' used to describe an array of objects in C++ (such as text strings). Don't let this confuse you, they are quite different: one of them is a mathematical term for a fixed-length list of numbers that you can do mathematical operations on, the other is a C++-specific term that means 'dynamically sizeable array'.

'ofVec3f has three member variables, x, y, and z, which allow to conveniently 'store 3D properties of an object such as its position, velocity, or 'acceleration.

ofVec3f v1; // v1.x is 0, v1.y is 0, v1.z is 0

v1.set(10, 50, 80); // now v1.x is 10, v1.y is 50, v1.z is 80

Using 'ofVec3f' greatly simplifies arithmetic operations in three dimensions. For example if you have two vectors 'v1' and 'v2', both of which represent a 3D change in position, you can find the total change of position of both of them just by doing an addition 'v1 + v2':

ofVec3f v1(5, 2, 1); 
// so now v1 represents walking 5 steps forward then 2 steps 
// sideways then 1 step upwards
ofVec3f v2;
v2.set(1, 1, 1); 
// so now v2 represents walking 1 step forward then 1 step 
// sideways then 1 step upwards
// what happens if you do v1 followed by v2?
// to find out just add v1 and v2 together:
ofVec3f result = v1 + v2; 
// result is (6, 3, 1), or 6 steps forward then 3 steps sideways
// then 2 steps upwards

You can scale an 'ofVec3f' by multiplying it with a float:

// walk 5 steps forward then 2 steps sideways then 1 step upwards
ofVec3f v1(5, 2, 1); 
// what happens if we do v1 three times?
ofVec3f result = v1 * 3; // result is (15, 6, 3), or 
// 15 steps forward, 6 steps sideways and 3 steps upwards

This also works for subtraction and division.

As you can see this really makes dealing with vectors as easy as dealing with single 'float's or 'int's, and can reduce the number of lines of code you have to write by half, at the same time making your code much easier to read and understand!

See Also: ofVec2f for 2D vectors; ofVec4f for 4D vectors

Construct a 3D vector

ofVec3f ()

Access components

getPtr ()

operator[] ()

set ()

Comparison

operator== ()

operator!= ()

match ()

isAligned ()

isAlignedRad ()

align ()

alignRad ()

Operators

operator+ ()

operator+= ()

operator- ()

operator-= ()

operator* ()

operator*= ()

operator/ ()

operator/= ()

Simple manipulations

getScaled ()

scale ()

getRotated ()

getRotatedRad ()

rotate ()

rotateRad ()

getMapped ()

map ()

Distance

distance ()

squareDistance ()

Interpolation

getInterpolated ()

interpolate ()

getMiddle ()

middle ()

average ()

Limit

getNormalized ()

normalize ()

getLimited ()

limit ()

Measurement

length ()

lengthSquared ()

angle ()

angleRad ()

Perpendicular

getPerpendicular ()

perpendicular ()

getCrossed ()

cross ()

dot ()

Attributes

x variable

y variable

z variable