tried this still not good with scene.camera

[Dale Griffiths]

Wondered if you could attach camera to the position of an object, obviously if you give the ball a radius your camera is stuck inside the ball so i tried making radius = 0. This does then do what I'd expect with the position of the ball and therefore camera moving out along the negative z axis, however the green floor is not visible. However if i manually zoom out with the track pad then I see the green square (it's as if the camera was way into the negative z direction so can't see the square , which shouldn't be the case) also once the square is in view after zooming it just stay there???

GlowScript 3.1 VPython

floor = box (pos=vec(0,0,0), size=vec(1000, 1000,1), color=color.green)

scene.camera.axis = vec(0,0,-1)

ball = sphere(pos=vec(0,0,20), radius=0)

scene.camera.pos = ball.pos

while True:

  rate(1)

  #scene.camera.pos.z += 1

  ball.pos.z += 1

  scene.camera.pos = ball.pos

  print(scene.camera.pos)

[Dale Griffiths]

Aha, this seems to work for some reason updating the axis as a vector from the camera to the floor in the while loop!

GlowScript 3.1 VPython

floor = box (pos=vec(0,0,0), size=vec(1000, 1000,1), color=color.green)

scene.camera.axis = vec(0,0,-1)

ball = sphere(pos=vec(0,0,20), radius=0)

scene.camera.pos = ball.pos

while True:

  rate(50)

  #scene.camera.pos.z += 1

  ball.pos.z += 1

  scene.camera.pos = ball.pos

  scene.camera.axis = floor.pos - scene.camera.pos

  print(scene.camera.pos)

[Bruce Sherwood]

Setting scene.camera.axis to vec(0,0,-1) changes scene.center

from <0,0,0> to <0,0,952>, very far from the floor.

Do review the effects of changing scene.camera.pos and scene.camera.axis here:

   https://www.glowscript.org/docs/VPythonDocs/canvas.html

Bruce