The project command takes a plot structure or object and produces a new plot structure or object.

In two dimensional case, an object can be projected on a given line.

In three dimensional case, an object can be projected on a given a line, or a given plane.

The result of a call to project is a 2-D or 3-D plot structure or object, which may be displayed with the plots:-display command. You can assign the data structure to a variable, save it in a file, then read it back in for redisplay.  For more information about plot data structures, see plot/structure.

Several commands in the plottools package can transform plots. For a list, see the plottools help page.  The plots:-changecoords and plots:-display commands can also be used to transform plots.

A point is represented as a list of either two real numbers (2-D) or three real numbers (3-D).

A line is represented as a list of two distinct points.

A plane is represented as a list of three distinct points.

$\mathrm{with}\left(\mathrm{plottools}\right)\:$

$\mathrm{with}\left(\mathrm{plots}\right)\:$

$p≔\mathrm{plot3d}\left(\sin \left(xy\right)+3\,x=-\mathrm{\pi }..\mathrm{\pi }\,y=-\mathrm{\pi }..\mathrm{\pi }\right)\:$

$q≔\mathrm{project}\left(p\,\left[\left[0\,0\,0\right]\,\left[1\,0\,0\right]\,\left[0\,1\,0\right]\right]\right)\:$

$r≔\mathrm{reflect}\left(p\,\left[\left[0\,0\,0\right]\,\left[1\,0\,0\right]\,\left[0\,1\,0\right]\right]\right)\:$

$\mathrm{display}\left(\left[p\,q\,r\right]\,\mathrm{lightmodel}=\mathrm{light4}\,\mathrm{orientation}=\left[60\,60\right]\right)$