Projects a 3D object. The x, y and z axes are modelled as lines in red, green and blue respectively. Needs descartes.py for the graphics, which also needs draw_line.py to draw lines. __________________

Commands: Up Arrow: Increment angle along x-axis. Down Arrow: Excrement angle along x-axis. Left Arrow: Increment angle along y-axis. Right Arrrow: Excrement angle along y-axis. Right Parenthesis: Increment angle along z-axis. Left Parenthesis: Excrement angle along z-axis. Plus Key: Zoom in on the origin. Minus Key: Zoom out on the origin.

More commands and improvements are yet to come; if you have any ideas please let me know on TI-Planet here: https://tiplanet.org/forum/viewtopic.php?f=100&t=27255

from math import *
from descartes import *
from ion import *
from time import *

def cube(s):
  c=[[[-s,s,s],[-s,s,-s]],
      [[-s,s,-s],[-s,-s,-s]],
      [[-s,-s,-s],[-s,-s,s]],
      [[-s,-s,s],[-s,s,s]],
      [[s,s,-s],[s,s,s]],
      [[s,s,s],[s,-s,s]],
      [[s,-s,s],[s,-s,-s]],
      [[s,-s,-s],[s,s,-s]],
      [[-s,s,-s],[s,s,-s]],
      [[-s,-s,-s],[s,-s,-s]],
      [[-s,-s,s],[s,-s,s]],
      [[-s,s,s],[s,s,s]]]
  return c

def axes(xa,ya,za,bgcol):
  R([[[-200,0,0],[200,0,0]]],xa,ya,za,'red',bgcol,False)
  R([[[0,-200,0],[0,200,0]]],xa,ya,za,'green',bgcol,False)
  R([[[0,0,-200],[0,0,200]]],xa,ya,za,'blue',bgcol,False)

def proj(c,col,bgcol,vertices=True):
  for e in c:
    v0,v1=e[0],e[1]
    line(v0[0],v0[1],v1[0],v1[1],col,bgcol,True)
    if vertices:
      fill(int(v0[0])-2,int(v0[1])+2,4,4,'red')

def R(c,xa,ya,za,col,bgcol,vertices=True):
  pc=[]
  for e in c:
    v0,v1=e
    x0,y0,z0=v0
    x1,y1,z1=v1

    pv0=[x0,cos(xa)*y0+-sin(xa)*z0,sin(xa)*y0+cos(xa)*z0]
    x0,y0,z0=pv0
    pv0=[cos(ya)*x0+sin(ya)*z0,y0,-sin(ya)*x0+cos(ya)*z0]
    x0,y0,z0=pv0
    pv0=[cos(za)*x0+-sin(za)*y0,sin(za)*x0+cos(za)*y0,z0]

    pv1=[x1,cos(xa)*y1+-sin(xa)*z1,sin(xa)*y1+cos(xa)*z1]
    x1,y1,z1=pv1
    pv1=[cos(ya)*x1+sin(ya)*z1,y1,-sin(ya)*x1+cos(ya)*z1]
    x1,y1,z1=pv1
    pv1=[cos(za)*x1+-sin(za)*y1,sin(za)*x1+cos(za)*y1,z1]

    pc.append([pv0,pv1])
  proj(pc,col,bgcol,vertices)

def graph():
  
  xa,ya,za=0,0,0
  dxa,dya,dza=0,0,0
  side=30
  draw=True
  while True:
    if keydown(KEY_UP):
      xa+=pi/40
      dxa+=1
      draw=True
    if keydown(KEY_DOWN):
      xa-=pi/40
      dxa-=1
      draw=True
    if keydown(KEY_RIGHT):
      ya-=pi/40
      dya-=1
      draw=True
    if keydown(KEY_LEFT):
      ya+=pi/40
      dya+=1
      draw=True
    if keydown(KEY_RIGHTPARENTHESIS):
      za+=pi/40
      dza+=1
      draw=True
    if keydown(KEY_LEFTPARENTHESIS):
      za-=pi/40
      dza-=1
      draw=True
    if keydown(KEY_PLUS):
      side+=1
      draw=True
    if keydown(KEY_MINUS):
      side-=1
      draw=True
    if draw:
      mulx,divx=dxa//gcd(40,dxa),40//gcd(40,dxa)
      muly,divy=dya//gcd(40,dya),40//gcd(40,dya)
      mulz,divz=dza//gcd(40,dza),40//gcd(40,dza)
      fill(-160,111,320,222,'black')
#    string('θx = '+str(round(xa,3)),-150,100,'black','red')
      if dxa==0:
        string('θx = 0',-150,100,'black','red')
      else:
        string('θx = '+(str(mulx)[:-1]) if abs(mulx)==1 else str(mulx)+'pi/'+str(divx),-150,100,'black','red')
#    string('θy = '+str(round(ya,3)),-150,80,'black','blue')
      if dya==0:
        string('θy = 0',-150,80,'black','green')
      else:
        string('θy = '+(str(muly)[:-1]) if abs(muly)==1 else str(muly)+'pi/'+str(divy),-150,80,'black','green')
#    string('θz = '+str(round(za,3)),-150,60,'black','green')
      if dza==0:
        string('θz = 0',-150,60,'black','blue')
      else:
        string('θz = '+(str(mulz)[:-1]) if abs(mulz)==1 else str(mulz)+'pi/'+str(divz),-150,60,'black','blue')
      string('x',140,100,'red','black')
      string('y',140,80,'green','black')
      string('z',140,60,'blue','black')
      R(cube(side),xa,ya,za,'white','black')
      axes(xa,ya,za,'black')
      draw=False
    sleep(0.05)

graph()