o.py

import math
def render_frame(A, B):
    cosA = math.cos(A)
    sinA = math.sin(A)
    cosB = math.cos(B)
    sinB = math.sin(B)
    char_output = []
    zbuffer = []
    for i in range(screen_height + 1):
        char_output.append([' '] * (screen_width + 0))
        zbuffer.append([0] * (screen_width + 0))
    theta = 0
    while (theta < 2* math.pi):
        theta += theta_spacing
        costheta = math.cos(theta)
        sintheta = math.sin(theta)
        phi = 0
        while (phi < 2*math.pi):
            phi += phi_spacing
            cosphi = math.cos(phi)
            sinphi = math.sin(phi)
            circlex = R2 + R1*costheta
            circley = R1*sintheta
            x = circlex*(cosB*cosphi + sinA*sinB*sinphi) - circley*cosA*sinB
            y = circlex*(sinB*cosphi - sinA*cosB*sinphi) + circley*cosA*cosB
            z = K2 + cosA*circlex*sinphi + circley*sinA
            ooz = 1/z
            xp = int(screen_width/2 + K1*ooz*x)
            yp = int(screen_height/2 - K1*ooz*y)
            L = cosphi*costheta*sinB - cosA*costheta*sinphi - sinA*sintheta + cosB*(cosA*sintheta - costheta*sinA*sinphi)
            if L > 0:
                if ooz > zbuffer[xp][yp]:
                    zbuffer[xp][yp] = ooz
                    luminance_index = L*8
                    char_output[xp][yp] = '.,-~:;=!*#$@'[int(luminance_index)]
    print('\x1b[H')
    for i in range(screen_height):
        for j in range(screen_width):
            print(char_output[i][j], end='')
        print()
theta_spacing = 0.07
phi_spacing = 0.02
R1 = 1
R2 = 2
K2 = 5
screen_width = 35
screen_height = 35
K1 = screen_width*K2*3/(8*(R1+R2))
print('\x1b[2J')
A = 1.0
B = 1.0
for i in range(250):
    render_frame(A, B)
    A += 0.08
    B += 0.03