Programming and Graphics

236 Introduction to C++ Programming and Graphics

Problems

7.6.1. Modify the codegraph2danmto display (a) a traveling square wave,

and (b) a traveling triangular wave.

7.6.2. Write a code that animates a rolling wheel containing seven rotating

spokes. The wheel should be rolling, not idly spinning.

7.7 Three-dimensional interactive graph Contents xi

In the most ambitious project, we build a code that plots a group of three-
dimensional lines in thexyzspace. The code will employ two ancillary func-
tions that use basicVoglecommands to move the cursor and draw straight
segments:

1. Functiondrawplot3dprepares the three-dimensional graph.


2. Functionplot3dtranstransforms the graph by rotating the axes and
   zooming in and out. In addition, it offers an option for printing and
   resetting the plotting parameters.

We discuss these two functions individually and then illustrate their use in a
plotting code.

Function drawplot3d

The implementation of the functiondrawplot3dis:

/*------------------------

drawplot3d

Draw a three-dimensional plot with axes

-------------------------*/

#include<fstream>

#include<iostream>

#include<iomanip>

#include<cmath>

#include "VOGLE/voglec++.h"

#include "plot3dglobals.h"

using namespace std;

void drawplot3d ()

{

//--- Prepare: