Use custom VTK with OSMesa wheel to build the docs (#1942)

* use our wheel

* install osmesa lib

* Delete extract-edges.py

* remove headless display install

* Update azure-pipelines.yml

* Update azure-pipelines.yml

* Trivial change

* another trivial change

* add back in modified extract edges

* remove trailing whitespace

* minor style changes

* ignore flake8 for osmnx import

Makefile

@@ -48,10 +48,8 @@ mypy:
 
 lint:
 	@echo "Linting with flake8"
-	# Check for codestyle
-	flake8 .
+	@flake8 .
 
 isort:
 	@echo "Formatting with isort"
-	# Check for trailing whitespace
 	isort .

azure-pipelines.yml

@@ -101,16 +101,12 @@ jobs:
       pip install -e .
     displayName: Install pyvista
 
-  - script: |      
-      .ci/setup_headless_display.sh
-      # python .ci/pyvista_test.py  # for debug
-    displayName: Install headless display
-
   - script: |
-      sudo apt-get install python3-tk pandoc
+      sudo apt-get update
+      sudo apt-get install python3-tk pandoc libosmesa6
       pip install -r requirements_docs.txt
     displayName: 'Install dependencies'
-
+ 
   - script: |
       EXAMPLES_PATH=$(python -c "import pyvista; print(pyvista.EXAMPLES_PATH)")
       mkdir -p EXAMPLES_PATH
@@ -132,6 +128,10 @@ jobs:
       path: '$(Build.SourcesDirectory)/doc/examples'
     displayName: Build pyvista doc examples cache
 
+  # note: built this wheel using Ubuntu 20.04.3 with OSMESA
+  - script: |
+      pip install https://github.com/pyvista/pyvista-wheels/raw/add_v9_1_0/vtk-osmesa-9.1.0-cp38-cp38-linux_x86_64.whl
+    displayName: "Install VTK build with osmesa 9.1.0"
   - script: |
       make -C doc html SPHINXOPTS="-w build_errors.txt -N"
     displayName: 'Build documentation'

doc/conf.py

@@ -292,9 +292,10 @@ def reset_pyvista(gallery_conf, fname):
     pyvista.set_plot_theme('document')
 
 
+# skip building the osmnx example if osmnx is not installed
 has_osmnx = False
 try:
-    import osmnx, fiona
+    import osmnx, fiona  # noqa: F401 isort: skip
     has_osmnx = True
 except:
     pass

examples/01-filter/extract-edges.py

@@ -4,7 +4,7 @@
 Extract Edges
 ~~~~~~~~~~~~~
 
-Extracts edges from a surface.
+Extract edges from a surface.
 """
 
 # sphinx_gallery_thumbnail_number = 2
@@ -19,30 +19,29 @@
 # 3. feature edges (edges used by two triangles and whose dihedral angle > feature_angle)
 # 4. manifold edges (edges used by exactly two polygons).
 #
-# This filter will extract those edges given a feature angle and return a dataset
+# The :func:`extract_feature_edges() <pyvista.PolyDataFilters.extract_feature_edges>`
+# filter will extract those edges given a feature angle and return a dataset
 # with lines that represent the edges of the original mesh.
-# To demonstrate, we will first extract the edges around Queen Nefertiti's eyes:
-
-# Load Queen Nefertiti mesh
-mesh = examples.download_nefertiti()
+#
+# To demonstrate, we will first extract the edges around a sample CAD model:
 
-# Extract the edges above a 12 degree feature angle
-edges = mesh.extract_feature_edges(12)
+# Download the example CAD model and extract all feature edges above 45 degrees
+mesh = examples.download_cad_model()
+edges = mesh.extract_feature_edges(45)
 
-# Render the edge lines on top of the original mesh
+# Render the edge lines on top of the original mesh.  Zoom in to provide a better figure.
 p = pv.Plotter()
 p.add_mesh(mesh, color=True)
 p.add_mesh(edges, color="red", line_width=5)
-# Define a camera position that will zoom to her eye
-p.camera_position = [(96.0, -197.0, 45.0), (7.0, -109.0, 22.0), (0, 0, 1)]
+p.camera.zoom(1.5)
 p.show()
 
+
 ###############################################################################
 # We can do this analysis for any :class:`pyvista.PolyData` object. Let's try
 # the cow mesh example:
 
 mesh = examples.download_cow()
-
 edges = mesh.extract_feature_edges(20)
 
 p = pv.Plotter()
@@ -59,6 +58,7 @@
 
 # Download a sample surface mesh with visible open edges
 mesh = examples.download_bunny()
+mesh
 
 ###############################################################################
 # We can get a count of the open edges with: