Merge pull request #21 from BigRoy/enhancement/prim_hierarchy_delegate

Enhancement: Prim Hierarchy Delegate and default prim / variant set features

README.md

@@ -10,6 +10,9 @@ The Qt components can be embedded in your own Qt interfaces and usually have
 a `stage` entrypoint that you should pass a `pxr.Usd.Stage` instance.
 
 However, a simple example Editor UI is also available to run standalone.
+
+![USD Editor](/assets/images/editor_screenshot.png "USD Editor")
+
 If you have the `usd_qtpy` package you can for example run it like:
 
 ```

usd_qtpy/__main__.py

@@ -23,11 +23,13 @@ def main():
     from pxr import Usd  # noqa
     from qtpy import QtWidgets  # noqa
     from usd_qtpy.editor import EditorWindow  # noqa
+    from usd_qtpy.style import load_stylesheet
 
     stage = Usd.Stage.Open(filepath)
     app = QtWidgets.QApplication()
     dialog = EditorWindow(stage=stage)
-    dialog.resize(600, 600)
+    dialog.resize(1200, 600)
+    dialog.setStyleSheet(load_stylesheet())
     dialog.show()
     app.exec_()
 

usd_qtpy/editor.py

@@ -1,6 +1,6 @@
 import logging
 
-from qtpy import QtWidgets
+from qtpy import QtWidgets, QtCore
 
 from . import (
     prim_hierarchy,
@@ -17,13 +17,22 @@
     HAS_VIEWER = False
 
 
-class EditorWindow(QtWidgets.QDialog):
+class EditorWindow(QtWidgets.QWidget):
     """Example editor window containing the available components."""
 
     def __init__(self, stage, parent=None):
         super(EditorWindow, self).__init__(parent=parent)
 
-        self.setWindowTitle("USD Editor")
+        title = "USD Editor"
+        if stage:
+            name = stage.GetRootLayer().GetDisplayName()
+            title = f"{title}: {name}"
+        self.setWindowTitle(title)
+
+        self.setWindowFlags(
+            self.windowFlags() |
+            QtCore.Qt.Dialog
+        )
 
         layout = QtWidgets.QVBoxLayout(self)
         splitter = QtWidgets.QSplitter(self)

usd_qtpy/layer_diff.py

@@ -1,3 +1,4 @@
+import contextlib
 import difflib
 
 from qtpy import QtWidgets, QtCore
@@ -6,6 +7,39 @@
 from .lib.qt import DifflibSyntaxHighlighter
 
 
+@contextlib.contextmanager
+def preserve_scroll(scroll_area):
+    """Preserve scrollbar positions by percentage after context."""
+    def get_percent(scrollbar):
+        value = scrollbar.value()
+        minimum = scrollbar.minimum()
+        maximum = scrollbar.maximum()
+        if value <= minimum:
+            return 0
+        if value >= maximum:
+            return 1
+        if minimum == maximum:
+            return 0
+        return (value - minimum) / (maximum - minimum)
+
+    def set_percent(scrollbar, percent):
+        minimum = scrollbar.minimum()
+        maximum = scrollbar.maximum()
+        value = minimum + ((maximum - minimum) * percent)
+        scrollbar.setValue(value)
+
+    horizontal = scroll_area.horizontalScrollBar()
+    h_percent = get_percent(horizontal)
+    vertical = scroll_area.verticalScrollBar()
+    v_percent = get_percent(vertical)
+    try:
+        yield
+    finally:
+        print(h_percent, v_percent)
+        set_percent(horizontal, h_percent)
+        set_percent(vertical, v_percent)
+
+
 class LayerDiffWidget(QtWidgets.QDialog):
     """Simple layer ASCII diff text view"""
     # TODO: Add a dedicated 'toggle listen' and 'refresh' button to the widget
@@ -26,7 +60,8 @@ def __init__(self,
         text_edit = QtWidgets.QTextEdit()
 
         # Force monospace font for readability
-        text_edit.setStyleSheet('* { font-family: "Courier"; }')
+        text_edit.setProperty("font-style", "monospace")
+        text_edit.setLineWrapMode(QtWidgets.QTextEdit.NoWrap)
         highlighter = DifflibSyntaxHighlighter(text_edit)
         text_edit.setPlaceholderText("Layers match - no difference detected.")
 
@@ -59,16 +94,18 @@ def refresh(self):
         a_ascii = layer_a.ExportToString()
         b_ascii = layer_b.ExportToString()
 
-        # Print diff
-        self._text_edit.clear()
-        for line in difflib.unified_diff(
+        generator = difflib.unified_diff(
             a_ascii.splitlines(),
             b_ascii.splitlines(),
             fromfile=self._layer_a_label or f"{layer_a.identifier} (A)",
             tofile=self._layer_b_label or f"{layer_b.identifier} (B)",
             lineterm=""
-        ):
-            self._text_edit.insertPlainText(f"{line}\n")
+        )
+
+        with preserve_scroll(self._text_edit):
+            self._text_edit.clear()
+            for line in generator:
+                self._text_edit.insertPlainText(f"{line}\n")
 
     def on_layers_changed(self, notice, sender):
         # TODO: We could also cache the ASCII of the USD files so that on

usd_qtpy/layer_editor.py

@@ -2,6 +2,7 @@
 import contextlib
 import logging
 from functools import partial
+from typing import List
 
 from qtpy import QtWidgets, QtCore, QtGui
 
@@ -11,6 +12,7 @@
 from .tree.base import AbstractTreeModelMixin
 from .lib.qt import schedule, iter_model_rows
 from .layer_diff import LayerDiffWidget
+from .resources import get_icon
 
 log = logging.getLogger(__name__)
 
@@ -53,18 +55,22 @@ def set_tips(widget, tip):
 
 
 class LayerItem(TreeItem):
-    __slots__ = ('layer', 'parent_layer')
+    __slots__ = ('layer', 'stack')
 
-    def __init__(self, layer: Sdf.Layer, parent_layer: Sdf.Layer = None):
-        if parent_layer:
-            separator = "<--sublayer-->"
-            key = separator.join([parent_layer.identifier, layer.identifier])
-        else:
-            key = layer.identifier
+    def __init__(self, layer: Sdf.Layer, parents: List[Sdf.Layer] = None):
+
+        # The key is the full layer stack (all parents) joined together
+        # by a unique separator so the layer identifier can uniquely appear
+        # anywhere on the layer stack
+        parents = parents or []
+        stack = list(parents)
+        stack.append(layer)
+        separator = "<--sublayer-->"
+        key = separator.join(stack_layer.identifier for stack_layer in stack)
 
         super(LayerItem, self).__init__(key=key)
         self.layer = layer
-        self.parent_layer = parent_layer
+        self.stack = stack
 
 
 class LayerStackModel(AbstractTreeModelMixin, QtCore.QAbstractItemModel):
@@ -284,15 +290,15 @@ def set_stage(self, stage):
             return
 
         self._stage = stage
+        self.refresh()
 
-        if self._listeners:
-            self.log.debug("Revoking Tf.Notice listeners: %s", self._listeners)
-            # Tf.Notice.Revoke(self._listeners)
-            for listener in self._listeners:
-                listener.Revoke()
-
-        self._listeners.clear()
+    def register_listeners(self):
+        stage = self._stage
         if stage and stage.GetPseudoRoot():
+            if self._listeners:
+                # Remove any existing listeners
+                self.revoke_listeners()
+
             self.log.debug("Adding Tf.Notice Listeners..")
             # Listen to changes
             self._listeners.append(Tf.Notice.Register(
@@ -327,7 +333,14 @@ def set_stage(self, stage):
             #     self.on_layers_changed,
             # ))
 
-        self.refresh()
+    def revoke_listeners(self):
+        if self._listeners:
+            self.log.debug("Revoking Tf.Notice listeners: %s", self._listeners)
+            # Tf.Notice.Revoke(self._listeners)
+            for listener in self._listeners:
+                listener.Revoke()
+
+        self._listeners.clear()
 
     @contextlib.contextmanager
     def reset_context(self):
@@ -351,8 +364,8 @@ def refresh(self):
                 return
 
             def add_layer(layer: Sdf.Layer, parent=None):
-                parent_layer = parent.layer if parent else None
-                layer_item = LayerItem(layer, parent_layer=parent_layer)
+                parent_layers = parent.stack if parent else None
+                layer_item = LayerItem(layer, parents=parent_layers)
                 item_tree.add_items(layer_item, parent=parent)
 
                 for sublayer_path in layer.subLayerPaths:
@@ -406,24 +419,16 @@ def __init__(self, layer, stage, parent=None):
         # Identifier label as display name
         label = QtWidgets.QLabel("", parent=self)
 
-        resources = os.path.join(os.path.dirname(__file__),
-                                 "resources",
-                                 "feathericons")
-
         # Save changes button
-        save_icon = QtGui.QIcon(os.path.join(resources, "save.svg"))
-        save = QtWidgets.QPushButton(self)
+        save = QtWidgets.QPushButton(get_icon("save"), "", self)
         set_tips(
             save, "Save layer to disk"
         )
-        save.setIcon(save_icon)
         save.setFixedWidth(25)
         save.setFixedHeight(25)
 
         # Set edit target (active or not button)
-        edit_icon = QtGui.QIcon(os.path.join(resources, "edit-2.svg"))
-        edit_target_btn = QtWidgets.QPushButton(self)
-        edit_target_btn.setIcon(edit_icon)
+        edit_target_btn = QtWidgets.QPushButton(get_icon("edit-2"), "", self)
         edit_target_btn.setCheckable(True)
         set_tips(
             edit_target_btn,
@@ -515,7 +520,6 @@ def on_save_layer(self):
         # TODO: Prompt for filepath if layer is anonymous?
         # TODO: Allow making filepath relative to parent layer?
         log.debug(f"Saving: {layer}")
-        log.debug(layer.ExportToString())
         layer.Save()
         # TODO: Do not update using this but base it off of signals from
         #  Sdf.Notice.LayerDidSaveLayerToFile
@@ -599,6 +603,7 @@ def on_view_context_menu(self, point):
 
             def show_layer_as_text():
                 text_edit = QtWidgets.QTextEdit(parent=self)
+                text_edit.setProperty("font-style", "monospace")
                 text_edit.setPlainText(layer.ExportToString())
                 text_edit.setWindowTitle(layer.identifier)
                 text_edit.setWindowFlags(QtCore.Qt.Dialog)
@@ -692,9 +697,11 @@ def on_add_layer(self, index):
             log.debug("Adding sublayer: %s", filename)
             layer.subLayerPaths.append(filename)
 
+    def showEvent(self, event):
+        self.model.register_listeners()
+
     def hideEvent(self, event: QtGui.QCloseEvent) -> None:
         # TODO: This should be on a better event when we know the window
         #   will be gone and unused after. The `closeEvent` doesn't seem
         #   to trigger by default on closing a parent dialog?
-        log.debug("Clearing stage connection..")
-        self.model.set_stage(None)  # clear listeners on close
+        self.model.revoke_listeners()

usd_qtpy/lib/qt.py

@@ -1,7 +1,7 @@
 import re
 import sys
 import logging
-from qtpy import QtCore, QtGui
+from qtpy import QtCore, QtGui, QtWidgets
 
 
 class SharedObjects:
@@ -93,3 +93,26 @@ def highlightBlock(self, text):
                 # Format the full block
                 self.setFormat(0, len(text), char_format)
                 return
+
+
+class DropFilesPushButton(QtWidgets.QPushButton):
+    """QPushButton that emits files_dropped signal when dropping files on it"""
+
+    files_dropped = QtCore.Signal(list)
+
+    def __init__(self, *args, **kwargs):
+        super(DropFilesPushButton, self).__init__(*args, **kwargs)
+        self.setAcceptDrops(True)
+
+    def dragEnterEvent(self, event):
+        if event.mimeData().hasUrls():
+            event.acceptProposedAction()
+        else:
+            super(DropFilesPushButton, self).dragEnterEvent(event)
+
+    def dropEvent(self, event):
+        if event.mimeData().hasUrls():
+            self.files_dropped.emit(event.mimeData().urls())
+            event.acceptProposedAction()
+        else:
+            super(DropFilesPushButton, self).dropEvent(event)