ResetCameraOrientation

vtk-examples/Python/Utilities/ResetCameraOrientation

Description¶

This example demonstrates how to reset the camera orientation.

In this case, the original orientation is stored, a new orientation calculated, and, finally the original orientation is restored. The original, new and restored orientations of the cone are displayed in one second intervals. After this you can interact with the scene.

To set the camera position, you can use:

SetPosition, SetFocalPoint, SetViewUp, SetDistance, SetClippingRange
Roll, Elevation, Azimuth
SetRoll, Pitch, Yaw

If you haven't used SetDistance or SetClippingRange remember to ren->ResetCamera(); or ren.ResetCamera().

Other languages

See (Cxx)

Question

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Code¶

ResetCameraOrientation.py

from time import sleep

# noinspection PyUnresolvedReferences
import vtkmodules.vtkRenderingOpenGL2
from vtkmodules.vtkCommonColor import vtkNamedColors
from vtkmodules.vtkFiltersSources import vtkConeSource
# noinspection PyUnresolvedReferences
from vtkmodules.vtkInteractionStyle import (
    vtkInteractorStyleTrackballCamera)
from vtkmodules.vtkRenderingCore import (
    vtkActor,
    vtkPolyDataMapper,
    vtkRenderWindow,
    vtkRenderWindowInteractor,
    vtkRenderer
)


def comma_separated_list(v, precision=6, width=10):
    """
    Produce a comma-separated string of numbers from a list.
    :param v: The list of floats.
    :param precision: Number of decimal places.
    :param width: The width.
    :return: A comma-separated string.
    """
    res = list()
    for p in v:
        res.append(f'{p:{width}.{precision}f}')
    return ','.join(res)


def get_orientation(ren):
    """
    Get the camera orientation.
    :param ren: The renderer.
    :return: The orientation parameters.
    """
    p = dict()
    camera = ren.GetActiveCamera()
    p['position'] = camera.GetPosition()
    p['focal point'] = camera.GetFocalPoint()
    p['view up'] = camera.GetViewUp()
    p['distance'] = camera.GetDistance()
    p['clipping range'] = camera.GetClippingRange()
    p['orientation'] = camera.GetOrientation()
    return p


def set_orientation(ren, p):
    """
    Set the orientation of the camera.
    :param ren: The renderer.
    :param p: The orientation parameters.
    :return:
    """
    camera = ren.GetActiveCamera()
    camera.SetPosition(p['position'])
    camera.SetFocalPoint(p['focal point'])
    camera.SetViewUp(p['view up'])
    camera.SetDistance(p['distance'])
    camera.SetClippingRange(p['clipping range'])


def main(argv):
    colors = vtkNamedColors()

    cone = vtkConeSource()
    cone.SetHeight(3.0)
    cone.SetRadius(1.0)
    cone.SetResolution(10)

    cone_mapper = vtkPolyDataMapper()
    cone_mapper.SetInputConnection(cone.GetOutputPort())

    cone_actor = vtkActor()
    cone_actor.SetMapper(cone_mapper)
    cone_actor.GetProperty().SetColor(colors.GetColor3d('Bisque'))

    ren = vtkRenderer()
    ren.AddActor(cone_actor)
    ren.SetBackground(colors.GetColor3d('MidnightBlue'))

    ren_win = vtkRenderWindow()
    ren_win.AddRenderer(ren)
    ren_win.SetSize(600, 600)
    ren_win.SetWindowName('ResetCameraOrientation')

    iren = vtkRenderWindowInteractor()
    iren.SetRenderWindow(ren_win)

    style = vtkInteractorStyleTrackballCamera()
    iren.SetInteractorStyle(style)

    camera = ren.GetActiveCamera()
    camera.SetRoll(15)
    camera.Elevation(-15)
    camera.Azimuth(30)
    ren.ResetCamera()

    ren_win.Render()
    original_orient = get_orientation(ren)
    s = f'{"Original orientation:":23s}'
    s += comma_separated_list(original_orient["orientation"])
    print(s)
    sleep(1)

    camera.SetPosition(-3.568189, 5.220048, 2.352639)
    camera.SetFocalPoint(-0.399044, -0.282865, 0.131438)
    camera.SetViewUp(0.623411, 0.573532, -0.531431)
    camera.SetDistance(6.727500)
    camera.SetClippingRange(3.001430, 11.434082)
    # No need to use ren.ResetCamera() as we have all the parameters.
    ren_win.Render()
    new_orient = get_orientation(ren)
    s = f'{"New orientation:":23s}'
    s += comma_separated_list(new_orient["orientation"])
    print(s)
    sleep(1)

    print('Reloading the original orientation.')
    set_orientation(ren, original_orient)
    ren_win.Render()
    check = get_orientation(ren)
    s = f'{"Final orientation:":23s}'
    s += comma_separated_list(check["orientation"])
    print(s)
    sleep(1)

    iren.Initialize()
    iren.Start()


if __name__ == '__main__':
    import sys

    main(sys.argv)