After drawing something by using Vispy, getting only white image

Question

As the title, only white image is printed.

below is my codes

import numpy as np
from vispy import io, scene

c = scene.SceneCanvas(keys='interactive', bgcolor='w', dpi=96)

view = c.central_widget.add_view()

xx, yy = np.arange(-1,1,.02),np.arange(-1,1,.02)
X,Y = np.meshgrid(xx,yy)
R = np.sqrt(X**2+Y**2)
Z = lambda t : 0.1*np.sin(10*R-2*np.pi*t)

surf = scene.visuals.SurfacePlot(xx, yy, Z(0), color=[0.5, 0.5, 0.5], shading='smooth')

view.add(surf)

img = c.render()
io.write_png("vispytest.png", img)

And I get vispytest.png

I'm using Xvfb on Linux.

Xvfb :1 -screen 0 2500x1500x24 -auth localhost

Thank you.

Answer 1

The problem is the focus of the camera, must modify, something similar to the following:

view.camera = scene.TurntableCamera(up='z', fov=60)

Complete code:

import numpy as np
from vispy import io, scene

c = scene.SceneCanvas(keys='interactive', bgcolor='w', dpi=96)

view = c.central_widget.add_view()
view.camera = scene.TurntableCamera(up='z', fov=60)

xx, yy = np.arange(-1,1,.02),np.arange(-1,1,.02)
X,Y = np.meshgrid(xx,yy)
R = np.sqrt(X**2+Y**2)
Z = lambda t : 0.1*np.sin(10*R-2*np.pi*t)

surf = scene.visuals.SurfacePlot(xx, yy, Z(0), color=[0.5, 0.5, 0.5], shading='smooth')

view.add(surf)

img = c.render()
io.write_png("vispytest.png", img)

vispytest.png