Canvas shows views from front (left), top (top right, front = down), and left (bottom right, front = left).
How many matrices should we show?
ident()
rotX(a)
rotY(a)
rotZ(a)
axis([fx,fy,fz], [ux,uy,uz])
trans(dx, dy, dz)
scale(sx, sy, sz)
persp(near, far, fovy, w_h)