Add option to always get screenshots from plotter shows

pyvista/__init__.py

@@ -37,6 +37,8 @@
 # Set where figures are saved
 FIGURE_PATH = os.environ.get("PYVISTA_FIGURE_PATH", None)
 
+ON_SCREENSHOT = os.environ.get("PYVISTA_ON_SCREENSHOT", "false").lower() == "true"
+
 # Send VTK messages to the logging module:
 send_errors_to_logging()
 

pyvista/plotting/plotter.py

@@ -14,6 +14,7 @@
 from threading import Thread
 import time
 from typing import Dict, Optional
+import uuid
 import warnings
 import weakref
 
@@ -6404,7 +6405,7 @@ def __init__(
                 notebook = scooby.in_ipykernel()
 
         self.notebook = notebook
-        if self.notebook:
+        if self.notebook or pyvista.ON_SCREENSHOT:
             off_screen = True
         self.off_screen = off_screen
 
@@ -6760,7 +6761,11 @@ def fun(plotter):
                     "A screenshot is unable to be taken as the render window is not current or rendering is suppressed."
                 )
         if _is_current:
-            self.last_image = self.screenshot(screenshot, return_img=True)
+            if pyvista.ON_SCREENSHOT:
+                filename = uuid.uuid4().hex
+                self.last_image = self.screenshot(filename, return_img=True)
+            else:
+                self.last_image = self.screenshot(screenshot, return_img=True)
             self.last_image_depth = self.get_image_depth()
         # NOTE: after this point, nothing from the render window can be accessed
         #       as if a user pressed the close button, then it destroys the

tests/conftest.py

@@ -11,6 +11,15 @@
 pyvista.OFF_SCREEN = True
 
 
+@fixture()
+def global_variables_reset():
+    tmp_screenshots = pyvista.ON_SCREENSHOT
+    tmp_figurepath = pyvista.FIGURE_PATH
+    yield
+    pyvista.ON_SCREENSHOT = tmp_screenshots
+    pyvista.FIGURE_PATH = tmp_figurepath
+
+
 @fixture(scope='session', autouse=True)
 def set_mpl():
     """Avoid matplotlib windows popping up."""

tests/plotting/test_plotter.py

@@ -4,6 +4,8 @@
 ./plotting/test_plotting.py
 
 """
+import os
+
 import numpy as np
 import pytest
 
@@ -464,3 +466,26 @@ def test_plotter_update_coordinates(sphere):
             raise RuntimeError("Convert error this method")
         if pv._version.version_info >= (0, 47):
             raise RuntimeError("Remove this method")
+
+
+def test_only_screenshots_flag(sphere, tmpdir, global_variables_reset):
+    pv.FIGURE_PATH = str(tmpdir)
+    pv.ON_SCREENSHOT = True
+
+    entries = os.listdir(pv.FIGURE_PATH)
+    pl = pv.Plotter()
+    pl.add_mesh(sphere)
+    pl.show()
+    entries_after = os.listdir(pv.FIGURE_PATH)
+    assert len(entries) + 1 == len(entries_after)
+
+    res_file = list(set(entries_after) - set(entries))[0]
+    pv.ON_SCREENSHOT = False
+    sphere_screenshot = "sphere_screenshot.png"
+    pl = pv.Plotter()
+    pl.add_mesh(sphere)
+    pl.show(screenshot=sphere_screenshot)
+    sphere_path = os.path.join(pv.FIGURE_PATH, sphere_screenshot)
+    res_path = os.path.join(pv.FIGURE_PATH, res_file)
+    error = pv.compare_images(sphere_path, res_path)
+    assert error < 100