Fix pygfx and pyside compatibility

Author: berendkleinhaneveld

collagraph/renderers/pygfx_renderer.py

@@ -1,3 +1,5 @@
+from typing import Callable
+
 import pygfx as gfx
 
 from . import Renderer
@@ -9,17 +11,42 @@
 class PygfxRenderer(Renderer):
     """Renderer for Pygfx objects"""
 
+    def __init__(self, *args, **kwargs):
+        super().__init__(*args, **kwargs)
+        self._on_change_handlers = set()
+
+    def add_on_change_handler(self, handler: Callable):
+        self._on_change_handlers.add(handler)
+
+    def remove_on_change_handler(self, handler: Callable):
+        self._on_change_handlers.remove(handler)
+
+    def _trigger(self):
+        for handler in self._on_change_handlers:
+            handler()
+
+    def register_asyncio(self):
+        import asyncio
+
+        from PySide6.QtAsyncio import QAsyncioEventLoopPolicy
+
+        policy = asyncio.get_event_loop_policy()
+        if not isinstance(policy, QAsyncioEventLoopPolicy):
+            asyncio.set_event_loop_policy(QAsyncioEventLoopPolicy())
+
     def create_element(self, type: str) -> gfx.WorldObject:
         """Create pygfx element for the given type"""
         type = type.lower().replace("-", "")
         if element_type := ELEMENT_TYPE_CACHE.get(type):
+            self._trigger()
             return element_type()
 
         attrs = dir(gfx)
         for attr in attrs:
             if attr.lower() == type:
                 element_type = getattr(gfx, attr)
                 ELEMENT_TYPE_CACHE[type] = element_type
+                self._trigger()
                 return element_type()
 
         raise ValueError(f"Can't create element of type: {type}")
@@ -34,9 +61,11 @@ def insert(
         anchor: gfx.WorldObject = None,
     ):
         parent.add(el, before=anchor)
+        self._trigger()
 
     def remove(self, el: gfx.WorldObject, parent: gfx.WorldObject):
         parent.remove(el)
+        self._trigger()
 
     def set_element_text(self, el, value: str):
         raise NotImplementedError
@@ -58,7 +87,14 @@ def set_attribute(self, obj, attr, value):
                 else:
                     DEFAULT_ATTR_CACHE[key] = default_value
 
-        setattr(obj, attr, value)
+        # Note: this check can be removed when the following PR
+        # has been included in a new release of observ (>0.15):
+        # https://github.com/fork-tongue/observ/pull/130
+        if val := getattr(value, "__target__", None):
+            setattr(obj, attr, val)
+        else:
+            setattr(obj, attr, value)
+        self._trigger()
 
     def remove_attribute(self, obj, attr, value):
         key = f"{type(obj).__name__}.{attr}"
@@ -78,6 +114,7 @@ def remove_attribute(self, obj, attr, value):
             setattr(obj, attr, val)
         else:
             delattr(obj, attr)
+        self._trigger()
 
     def add_event_listener(self, el, event_type, value):
         el.add_event_handler(value, event_type)

collagraph/renderers/pyside_renderer.py

@@ -1,5 +1,5 @@
 from collections import defaultdict
-from functools import lru_cache
+from functools import lru_cache, partial
 import logging
 from typing import Any, Callable
 from warnings import warn
@@ -402,6 +402,11 @@ def add_event_listener(self, el: Any, event_type: str, value: Callable):
                 # a QObject?) results in a SystemError. Lambdas though _can_ function
                 # as a slot, so when creating a slot of the value fails, retry with
                 # a simple lambda.
+                if isinstance(value, partial):
+                    # In the case that value is a partial object, Pyside 6.9.2 spits
+                    # out a warning 'PytestUnraisableExceptionWarning'. Wrapping the
+                    # partial in a lambda seems to do the trick
+                    raise SystemError
                 slot = QtCore.Slot()(value)
             except SystemError:
                 # TODO: with some inspection we might be able to figure out the

examples/pygfx/combined-example.py

@@ -2,9 +2,9 @@
 Example of how to render lists, tables and trees.
 """
 
-from observ import reactive
-from point_cloud import materials, PointCloud, sphere_geom
 import pygfx as gfx
+from observ import reactive
+from point_cloud import PointCloud, materials
 from PySide6 import QtWidgets
 from wgpu.gui.qt import WgpuCanvas
 
@@ -41,10 +41,10 @@ def mounted(self):
             h(
                 "Mesh",
                 {
+                    "geometry": gfx.sphere_geometry(),
+                    "material": materials["other"],
                     "name": "Hip",
                     "local.position": [2, 2, 2],
-                    "geometry": sphere_geom,
-                    "material": materials["other"],
                 },
             ),
         )
@@ -54,9 +54,8 @@ def mounted(self):
         def animate():
             renderer.render(container, camera)
 
-        self.gui.render(
-            element, container, callback=lambda: self.element.request_draw(animate)
-        )
+        self.gui.renderer.add_on_change_handler(lambda: self.element.request_draw(animate))
+        self.gui.render(element, container)
 
     def render(self):
         return h("WgpuCanvas", {"minimum_height": 400, "minimum_width": 600})
@@ -103,7 +102,7 @@ def remove(event):
     renderer.register_element("WgpuCanvas", WgpuCanvas)
     gui = cg.Collagraph(renderer=renderer)
 
-    state = reactive({"count": 50})
+    state = reactive({"count": 1000})
 
     # Define Qt structure and map state to the structure
     element = h(Example, state)

examples/pygfx/component-example.py

@@ -8,9 +8,9 @@
 class Button(cg.Component):
     geometry = gfx.box_geometry()
     materials = {
-        "default": gfx.MeshPhongMaterial(color=[1.0, 0.5, 0.0]),
-        "pressed": gfx.MeshPhongMaterial(color=[0.0, 0.5, 0.0]),
-        "hovered": gfx.MeshPhongMaterial(color=[1.0, 0.2, 0.0]),
+        "default": gfx.MeshPhongMaterial(color=[1.0, 0.5, 0.0], pick_write=True),
+        "pressed": gfx.MeshPhongMaterial(color=[0.0, 0.5, 0.0], pick_write=True),
+        "hovered": gfx.MeshPhongMaterial(color=[1.0, 0.2, 0.0], pick_write=True),
     }
 
     def __init__(self, *args, **kwargs):

examples/pygfx/point_cloud.py

@@ -6,15 +6,47 @@
 
 sphere_geom = gfx.sphere_geometry(radius=0.5)
 materials = {
-    "default": gfx.MeshPhongMaterial(color=[1, 1, 1]),
-    "selected": gfx.MeshPhongMaterial(color=[1, 0, 0]),
-    "hovered": gfx.MeshPhongMaterial(color=[1, 0.6, 0]),
-    "other": gfx.MeshPhongMaterial(color=[1, 0, 0.5]),
+    "default": gfx.MeshPhongMaterial(color=[1, 1, 1], pick_write=True),
+    "selected": gfx.MeshPhongMaterial(color=[1, 0, 0], pick_write=True),
+    "hovered": gfx.MeshPhongMaterial(color=[1, 0.6, 0], pick_write=True),
+    "other": gfx.MeshPhongMaterial(color=[1, 0, 0.5], pick_write=True),
 }
 
 
+def rand_point():
+    return (
+        random.randint(-20, 20),
+        random.randint(-20, 20),
+        random.randint(-20, 20),
+    )
+
+
+def point(index, selected, hovered, set_selected, set_hovered):
+    material = (
+        "selected"
+        if index == selected
+        else "hovered"
+        if index == hovered
+        else "default"
+    )
+    return h(
+        "Mesh",
+        {
+            "geometry": sphere_geom,
+            "material": materials[material],
+            "local.position": positions[index],
+            "key": index,
+            "on_click": lambda event: set_selected(index),
+            "on_pointer_move": lambda event: set_hovered(index),
+        },
+    )
+
+
+positions = []
+
+
 def PointCloud(props):
-    random.seed(0)
+    global positions
 
     def set_hovered(index):
         props["hovered"] = index
@@ -25,34 +57,23 @@ def set_selected(index):
         else:
             props["selected"] = index
 
-    def random_point(index, selected, hovered):
-        material = materials["default"]
-        if index == selected:
-            material = materials["selected"]
-        elif index == hovered:
-            material = materials["hovered"]
-        return h(
-            "Mesh",
-            {
-                "geometry": sphere_geom,
-                "material": material,
-                "local.position": [
-                    random.randint(-10, 10),
-                    random.randint(-10, 10),
-                    random.randint(-10, 10),
-                ],
-                "key": index,
-                "on_click": lambda event: set_selected(index),
-                "on_pointer_move": lambda event: set_hovered(index),
-            },
-        )
 
     selected = props.get("selected", -1)
     hovered = props.get("hovered", -1)
     number_of_points = props.get("count", 50)
 
+    if len(positions) > number_of_points:
+        positions = positions[:number_of_points]
+    elif len(positions) < number_of_points:
+        positions.extend(
+            [rand_point() for _ in range(number_of_points - len(positions))]
+        )
+
     return h(
         "Group",
         {},
-        *[random_point(i, selected, hovered) for i in range(number_of_points)],
+        *[
+            point(i, selected, hovered, set_selected, set_hovered)
+            for i in range(number_of_points)
+        ],
     )

examples/pygfx/pygfx-example.py

@@ -31,7 +31,7 @@
             # When increasing this number, it will take longer
             # and longer for pygfx to create the render pipeline
             # (compiling shaders and such), so be careful...
-            {"count": 50},
+            {"count": 500},
         ),
         h(
             "Mesh",

examples/pygfx/pygfx-slider-example.py

@@ -32,7 +32,7 @@ def render(self):
 
 class Scrubber(cg.Component):
     scrubber_geometry = gfx.sphere_geometry()
-    scrubber_material = gfx.MeshPhongMaterial(color=[0.5, 1, 0.5])
+    scrubber_material = gfx.MeshPhongMaterial(color=[0.5, 1, 0.5], pick_write=True)
 
     def __init__(self, *args, **kwargs):
         super().__init__(*args, **kwargs)

tests/test_pygfx_renderer.py

@@ -79,12 +79,12 @@ def test_pygfx_attributes():
     # Set and unset attributes on Mesh
     mesh = gfx.Mesh()
 
-    # Custom attribute 'name'
-    renderer.set_attribute(mesh, "name", "foo")
-    assert mesh.name == "foo"
+    # Custom attribute 'foo'
+    renderer.set_attribute(mesh, "foo", "foo")
+    assert mesh.foo == "foo"
 
-    renderer.remove_attribute(mesh, "name", "foo")
-    assert not hasattr(mesh, "name")
+    renderer.remove_attribute(mesh, "foo", "foo")
+    assert not hasattr(mesh, "foo")
 
     # Position attribute
     original_position_contents = mesh.local.position.tolist()
@@ -105,7 +105,7 @@ def test_pygfx_attributes():
 
     # Matrix attribute
     original_matrix_contents = mesh.local.matrix.tolist()
-    matrix = [[2, 0, 0, 0], [0, 2, 0, 0], [0, 0, 2, 0], [0, 0, 0, 2]]
+    matrix = [[2, 0, 0, 0], [0, 2, 0, 0], [0, 0, 2, 0], [0, 0, 0, 1]]
     renderer.set_attribute(mesh, "local.matrix", matrix)
     assert mesh.local.matrix.tolist() == matrix