add test for curves, fix traitlets deprecation warning

yt_idv/scene_annotations/grid_outlines.py

@@ -14,7 +14,7 @@ class GridOutlines(SceneAnnotation):
     name = "grid_outline"
     data = traitlets.Instance(GridPositions)
     box_width = traitlets.CFloat(0.25)  # quarter of a dx
-    box_color = traitlets.Tuple((1.0, 1.0, 1.0), trait=traitlets.CFloat())
+    box_color = traitlets.Tuple((1.0, 1.0, 1.0)).tag(trait=traitlets.CFloat())
     box_alpha = traitlets.CFloat(1.0)
 
     def draw(self, scene, program):

yt_idv/scene_components/blocks.py

@@ -27,8 +27,8 @@ class BlockRendering(SceneComponent):
     tf_min = traitlets.CFloat(0.0)
     tf_max = traitlets.CFloat(1.0)
     tf_log = traitlets.Bool(True)
-    slice_position = traitlets.Tuple((0.5, 0.5, 0.5), trait=traitlets.CFloat())
-    slice_normal = traitlets.Tuple((1.0, 0.0, 0.0), trait=traitlets.CFloat())
+    slice_position = traitlets.Tuple((0.5, 0.5, 0.5)).tag(trait=traitlets.CFloat())
+    slice_normal = traitlets.Tuple((1.0, 0.0, 0.0)).tag(trait=traitlets.CFloat())
 
     priority = 10
 

yt_idv/scene_components/curves.py

@@ -14,7 +14,7 @@ class CurveRendering(SceneComponent):
     name = "curve_rendering"
     data = traitlets.Instance(CurveData, help="The curve data.")
     line_width = traitlets.CFloat(1.0)
-    curve_rgba = traitlets.Tuple((1.0, 1.0, 1.0, 1.0), trait=traitlets.CFloat())
+    curve_rgba = traitlets.Tuple((1.0, 1.0, 1.0, 1.0)).tag(trait=traitlets.CFloat())
     priority = 10
 
     def render_gui(self, imgui, renderer, scene):

yt_idv/tests/test_yt_idv.py

@@ -2,12 +2,15 @@
 
 import base64
 
+import numpy as np
 import pytest
 import yt
 import yt.testing
 from pytest_html import extras
 
 import yt_idv
+from yt_idv.scene_components.curves import CurveCollectionRendering, CurveRendering
+from yt_idv.scene_data.curve import CurveCollection, CurveData
 
 
 @pytest.fixture(autouse=True)
@@ -116,3 +119,30 @@ def test_annotate_text(osmesa_empty, image_store):
 def test_isocontour_functionality(osmesa_fake_amr, image_store):
     osmesa_fake_amr.scene.components[0].render_method = "isocontours"
     image_store(osmesa_fake_amr)
+
+
+def test_curves(osmesa_fake_amr, image_store):
+    # add a single curve
+
+    curved = CurveData()
+    x1d = np.linspace(0, 1, 10)
+    xyz = np.column_stack([x1d, x1d, x1d])
+    curved.add_data(xyz)
+    curve_render = CurveRendering(data=curved, curve_rgba=(1.0, 0.0, 0.0, 1.0))
+    curve_render.display_name = "single streamline"
+    osmesa_fake_amr.scene.data_objects.append(curved)
+    osmesa_fake_amr.scene.components.append(curve_render)
+
+    curve_collection = CurveCollection()
+    curve_collection.add_curve(xyz * 2.0)
+    curve_collection.add_curve(xyz * 3.0)
+    curve_collection.add_data()  # call add_data() after done adding curves
+
+    cc_render = CurveCollectionRendering(data=curve_collection)
+    cc_render.display_name = "multiple streamlines"
+    osmesa_fake_amr.scene.data_objects.append(curve_collection)
+    osmesa_fake_amr.scene.components.append(cc_render)
+
+    image_store(osmesa_fake_amr)
+
+    CurveCollection