Extension: omni.kit.scene_view.opengl-1.3.0

Documentation Generated: Dec 17, 2024

Overview#

Introduction#

omni.kit.scene_view.opengl provides an OpenGL drawing backend for omni.ui.scene. The usage is the same as omni.ui.scene for creating items, the only difference is in how the top-level SceneView object is created.

How to create a simple OpenGLSceneView#

Python#

  1. Import the required packages:

import omni.ui as ui
from omni.ui_scene import scene as sc
from omni.kit.scene_view.opengl import OpenGLSceneView

  1. Create a simple model to deliver view and projection to the omni.ui.scene.SceneView\

class SimpleModel(sc.AbstractManipulatorModel):
    def __init__(self, view = None, projection = None):
        super().__init__()
        self.__view = view or [0.7071067811865476, -0.4082482839677536, 0.5773502737830688, 0,
                               2.7755575615628914e-17, 0.8164965874238355, 0.5773502600027396, 0,
                               -0.7071067811865477, -0.40824828396775353, 0.5773502737830687, 0,
                               5.246555321336316e-14, -0.0000097441642310514, -866.0254037844385, 1]
        self.__projection = projection or [1.7320507843521864, 0, 0, 0,
                                           0, 2.911189413558437, 0, 0,
                                           0, 0, -1.00000020000002, -1,
                                           0, 0, -2.00000020000002, 0]

    def get_as_floats(self, item):
        """Called by SceneView to get projection and view matrices"""
        if item == self.get_item("projection"):
            return self.__projection
        if item == self.get_item("view"):
            return self.__view

  1. Create an omni.ui.Window and an OpenGLSceneView in it.

window = ui.Window("OpenGLSceneView", width=512, height=512)
with window.frame:
    gl_sceneview = OpenGLSceneView(SimpleModel())
    with gl_sceneview.scene:
        sc.Arc(250, axis=0, tesselation=64, color=[1, 0, 0, 1])
        sc.Arc(250, axis=1, tesselation=64, color=[0, 1, 0, 1])
        sc.Arc(250, axis=2, tesselation=64, color=[0, 0, 1, 1])

Depth Compositing#

Because the drawing is done with OpenGL, it is also possible to do in Viewport drawing that is depth-composited. This can be accomplished with the ViewportOpenGLSceneView class, which also handles setting up the Viewport to output a depth channel to clip against.

Python#

from omni.ui_scene import scene as sc
from omni.kit.scene_view.opengl import ViewportOpenGLSceneView
from omni.kit.viewport.utility import get_active_viewport_window

def build_fn(gl_scene_view):
    with gl_scene_view.scene:
        sc.Arc(45, axis=1, tesselation=64, color=[1, 0.9, 0.4, 1], wireframe=False, thickness=50)

# Use a static helper method to set everything up
# Just provide a ViewportWindow, unique identifier, and a callable function to build the scene
#
ui_frame, gl_scene_view = ViewportOpenGLSceneView.create_in_viewport_window(get_active_viewport_window(),
                                                                            "demo.unique.identifier",
                                                                            build_fn)

Further reading#

Omni UI Scene

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