I am trying to port my connector from Vanilla USD to USDRT. Hence I am creating the prims directly in fabric and applying transforms to it using using RtXformable API.
Cone
Spherelink .
As described in the post , I created following attributes
CreateWorldExtentAttr
CreateFabricHierarchyWorldMatrixAttr
CreateFabricHierarchyLocalMatrixAttr
_worldVisibility
purpose
But it is not working as expected. Can anyone give me some pointers which I am missing to set while working with USDRT.
Ok let me ask the dev team that works on USDRT and get back to you.
Thanks @Richard3D . Looking forward for your reply. Kind of stuck with my implementation.
We have example extensions at kit-extension-template-cpp/source/extensions at main · NVIDIA-Omniverse/kit-extension-template-cpp · GitHub
omni.example.usdrt_meshomni.example.cpp.usdrtomni.example.python.usdrt
This this line specifically:
def create_mesh_usdrt(stage: usdrt.Usd.Stage, prim_path: str, num_x_divisions: int, num_z_divisions: int):
self.sub = update_stream.create_subscription_to_pop(on_update, name="omni.example.python.usdrt_mesh.on_update")
return
def get_usdrt_stage() -> usdrt.Usd.Stage:
ctx = omni.usd.get_context()
stage = usdrt.Usd.Stage.Attach(ctx.get_stage_id())
return stage
def create_mesh_usdrt(stage: usdrt.Usd.Stage, prim_path: str, num_x_divisions: int, num_z_divisions: int):
mesh = usdrt.UsdGeom.Mesh.Define(stage, prim_path)
# Create the vertices and face counts
vertices = calculate_mesh_vertices(num_x_divisions, num_z_divisions, 0)
face_vertex_counts = []
face_vertex_indices = []
for z in range(num_z_divisions):
for x in range(num_x_divisions):
vertex0 = z * (num_x_divisions + 1) + x
Thanks @Richard3D for the reply. I have the following code for generating cube and then rescaling it. After execution the cube gets generated in the viewport but it does not rescale.
import omni.usd
xformable = Rt.Xformable(prim)
Hey @rashik.thalappully
The issue with your code above is a misuse of SetScale()
import omni.usd
from usdrt import Usd, Sdf, Gf, UsdGeom, Rt
# Get USD stage
usd_context = omni.usd.get_context()
stage = Usd.Stage.Attach(usd_context.get_stage_id())
# Define a cube
prim = stage.DefinePrim("/Ground/Cube", "Cube")
# Set the extent
rtbound = Rt.Boundable(prim)
world_ext = rtbound.CreateWorldExtentAttr()
world_ext.Set(Gf.Range3d(Gf.Vec3d(-0.5, -0.5, -0.5), Gf.Vec3d(0.5, 0.5, 0.5)))
# Apply scale using FabricHierarchyLocalMatrix
xformable = Rt.Xformable(prim)
# Create a scale matrix
scale_vec = Gf.Vec3d(20.0, 10.0, 5.0)
scale_matrix = Gf.Matrix4d(1.0) # Identity
scale_matrix.SetScale(scale_vec)
# Set it on the attribute
xform_attr = xformable.CreateFabricHierarchyLocalMatrixAttr(scale_matrix)
Hi @AshleyG_NVIDIA
Thanks for the reply. I have updated the code as follows
import omni.usd
from usdrt import Usd, Sdf, Gf, UsdGeom,Rt
usd_context = omni.usd.get_context()
stage = Usd.Stage.Attach(usd_context.get_stage_id())
prim = stage.DefinePrim("/World/Cube", "Cube")
rtbound = Rt.Boundable(prim)
world_ext = rtbound.CreateWorldExtentAttr()
world_ext.Set(Gf.Range3d(Gf.Vec3d(-0.5, -0.5, -0.5), Gf.Vec3d(0.5, 0.5, 0.5)))
xformable = Rt.Xformable(prim)
attr = xformable.GetFabricHierarchyLocalMatrixAttr()
if not attr:
print("CreateFabricHierarchyLocalMatrixAttr")
xformable.CreateFabricHierarchyLocalMatrixAttr()
attr = xformable.GetFabricHierarchyLocalMatrixAttr()
current_xform = attr.Get()
current_xform.SetScale(Gf.Vec3d(20.0, 100.0, 5.0))
attr.Set(current_xform)
print(current_xform)
print(attr.Get())
but still does not scale. Please refer the following screenshot to see the output. But the attribute value is updated with the new value.
Hi,
Unfortunately the World Space Matrix update code only considers prims that are fully “connected” in the Fabric Hierarchy, and the USDRT API has a bug in kit 106 where it does not “autoconnect” prims defined in USDRT. This bug is already fixed for Kit 107.
Blockquote
Hi @abaillet
During my experimentation yesterday, I have the following code snippet where scaling was working.
import omni.usd
from usdrt import Usd, Sdf, Gf, UsdGeom,Rt
usd_context = omni.usd.get_context()
stage = Usd.Stage.Attach(usd_context.get_stage_id())
prim = stage.DefinePrim("/World/Cube", "Cube")
rtbound = Rt.Boundable(prim)
world_ext = rtbound.CreateWorldExtentAttr()
world_ext.Set(Gf.Range3d(Gf.Vec3d(-0.5, -0.5, -0.5), Gf.Vec3d(0.5, 0.5, 0.5)))
xformable = Rt.Xformable(prim)
localAttr = xformable.GetFabricHierarchyLocalMatrixAttr()
if not localAttr:
print("CreateFabricHierarchyLocalMatrixAttr")
xformable.CreateFabricHierarchyLocalMatrixAttr()
worldAttr = xformable.GetFabricHierarchyWorldMatrixAttr()
if not worldAttr:
print("CreateFabricHierarchyWorldMatrixAttr")
xformable.CreateFabricHierarchyWorldMatrixAttr()
localAttr = xformable.GetFabricHierarchyLocalMatrixAttr()
current_xform = localAttr.Get()
current_xform.SetScale(Gf.Vec3d(20.0, 100.0, 5.0))
localAttr.Set(current_xform)
print(current_xform)
print(localAttr.Get())
The only difference is
Created ‘CreateFabricHierarchyWorldMatrixAttr’ and updated the Local Matrix only, then the scaling was working as shown the picture below.
I noticed that the shape appears in the viewport even without setting the extend attributes when the Fabric delegate is enabled. Are these attributes not mandatory for display?
Additionally, I installed Kit 107 , but the usdrt.scenegraph version is still 7.5.1 , the same as in Kit 106.5.0 . Has the fix already been included in version 7.5.1 ?
Thanks for your clarification!
