Create an Orthographic Camera
You can define a new camera on a stage using UsdGeom.Camera
. The Camera prim has a projection
attribute that can be set to orthographic
.
from pxr import Sdf, Usd, UsdGeom
def create_orthographic_camera(stage: Usd.Stage, prim_path: str="/World/MyOrthoCam") -> UsdGeom.Camera:
"""Create an orthographic camera
Args:
stage (Usd.Stage): A USD Stage to create the camera on.
prim_path (str, optional): The prim path for where to create the camera. Defaults to "/World/MyOrthoCam".
"""
camera_path = Sdf.Path(prim_path)
usd_camera = UsdGeom.Camera.Define(stage, camera_path)
usd_camera.CreateProjectionAttr().Set(UsdGeom.Tokens.orthographic)
return usd_camera
#############
# Full Usage
#############
cam_path = "/World/MyOrthoCam"
stage: Usd.Stage = Usd.Stage.CreateInMemory()
root_prim = UsdGeom.Xform.Define(stage, Sdf.Path("/World"))
stage.SetDefaultPrim(root_prim.GetPrim())
camera = create_orthographic_camera(stage, cam_path)
usda = stage.GetRootLayer().ExportToString()
print(usda)
# Check that the camera was created
prim = camera.GetPrim()
assert prim.IsValid()
assert camera.GetPath() == Sdf.Path(cam_path)
assert prim.GetTypeName() == "Camera"
projection = camera.GetProjectionAttr().Get()
assert projection == UsdGeom.Tokens.orthographic
The CreatePrimWithDefaultXform
command in Kit can create a Camera prim and you can optionally set camera attributes values during creation. You must use the attribute token names as the keys for the attributes
dictionary. In Omniverse applications, you can explore the names by hovering over a property label in the Property Window and reading it from the tooltip.
import omni.kit.commands
from pxr import UsdGeom
def create_orthographic_camera(prim_path: str="/World/MyOrthoCam"):
"""Create an orthographic camera
Args:
prim_path (str, optional): The prim path where the camera should be created. Defaults to "/World/MyOrthoCam".
"""
omni.kit.commands.execute("CreatePrimWithDefaultXform",
prim_type="Camera",
prim_path="/World/MyOrthoCam",
attributes={"projection": UsdGeom.Tokens.orthographic}
)
#############
# Full Usage
#############
import omni.usd
# Create an orthographic camera at /World/MyOrthoCam
path = "/World/MyOrthoCam"
create_orthographic_camera(path)
# Check that the camera was created
stage = omni.usd.get_context().get_stage()
prim = stage.GetPrimAtPath(path)
assert prim.IsValid() == True
assert prim.GetTypeName() == "Camera"
projection = prim.GetAttribute("projection").Get()
assert projection == UsdGeom.Tokens.orthographic
This is an example USDA result from creating a Camera and setting the projection
to orthographic
. All other Properties are using the default values from the UsdGeomCamera
schema definition.
#usda 1.0
(
defaultPrim = "World"
)
def Xform "World"
{
def Camera "MyOrthoCam"
{
token projection = "orthographic"
}
}