Makie - Camera position

Specific Domains Visualization
1

Hi Everyone,

i have been using the Makie for a while. particularly, I like the 3D reconstruction function.
the 3D reconstructive function allow me create the color code 3D plot from the 3D electron microscopy.
however, few month ago, the cameracontrol function start to not work. I’m not sure if syntax changed or any other modification needed?
i have been spending some time to ask different people including julia slack #helpdesk.
but, not clear solution for it. can anyone help with it?

here is my original code that has been working perfectly.

using GLMakie, FileIO, LinearAlgebra, Images

begin
    img = load("CG/200.png")
    #img = Gray.(frame)
    #img = imresize(img, (384, 684))
    w, h = size(img)
    ret = adjust_histogram(img, ContrastStretching(t = 5, slope = 4))
    f(x, y) = img[x,y]
    k =  4
    z = Float32[100f(x,y) for x in 1:k:w, y in 1:k:h]
end
fig = Figure()
#lscene = LScene(fig[1, 1], scenekw = (camera = cam3d!, raw = false))
lscene = LScene(fig[1, 1])
scene = surface(1:k:w, 1:k:h, z, colormap = :Paired_10)

  #control the camera position
   cam = cameracontrols(scene)
            #cam.lookat[] = [0,0,200]
   cam.eyeposition[] = [3000,200,20000]
   update_cam!(scene)

thank you
best
KP

2

I’d guess you’re not passing a scene but a Figure, LScene, Axis3 or FigureAxisPlot. You want something like this:

fig = Figure()
lscene = LScene(fig[1, 1])
# plot! to lscene

scene = lscene.scene
# camera stuff

If that’s not it, it might because the more recent camera changes. Though I don’t think it would mess with something like this. You could try a more direct

cam = cameracontrols(scene)
update_cam!(scene, cam, Vec3f(3000, 200, 20_000), cam.lookat[])
3

Dear Frederic,

great, thanks for your reply! first of all, I really appreciate your feedback.
i modified the code with the surface plot but “cam = cameracontrols(scene)” this part is not working.

Screenshot from 2021-10-05 19-18-01
Screenshot from 2021-10-05 19-18-011313×448 72.5 KB

here is the snapshot in my workstation.
would you check what might be wrong?
it could be a simple problem, but I cannot figure it out from my limited knowledge.
thanks much in advance
best
KP

4 
fig = Figure()
lscene = LScene(fig[1, 1])
surface!(lscene, ...)

cam = cameracontrols(lscene.scene)
cam.lookat[] = [0, 0, 200]
cam.eyeposition[] = [3000, 200, 2000]
update_cam!(lscene.scene, cam) # not sure if there is a method without cam

Makie.save(..., fig) # fig is the root object
5

great!! works for me! thanks much

6

Somehow it is not possible to change the up direction using this approach. Here’s a MWE of the problem

using Makie
using FileIO
using GLMakie

catmesh = FileIO.load(assetpath("cat.obj"))


fig = Figure()
scene = LScene(fig[1, 1])
mesh!(scene, catmesh, shading=true, color = :blue)

cam = cameracontrols(scene.scene)
cam.lookat[] = [0, 0, 200]
cam.eyeposition[] = [3000, 200, 2000]
cam.upvector[] = [0, 1, 0]
update_cam!(scene.scene, cam) # not sure if there is a method without cam

fig
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7

That’s because cats are tiny and executing fig at the end re-centers the scene. Try

using FileIO
using GLMakie

catmesh = FileIO.load(assetpath("cat.obj"))


fig = Figure()
scene = LScene(fig[1, 1], scenekw=(center=false,))
mesh!(scene, catmesh, shading=true, color = :blue)

cam = cameracontrols(scene.scene)
cam.lookat[] = [0, 0, 200] ./ 1000
cam.eyeposition[] = [3000, 200, 2000] ./ 1000
cam.upvector[] = [0, 1, 0]
update_cam!(scene.scene, cam)

fig
1 Like