Halo catalog example

.gitignore

@@ -124,3 +124,4 @@ report.html
 
 *.DS_Store
 *.swp
+*.h5

examples/halo_rendering_as_particles.py

@@ -0,0 +1,51 @@
+import os
+
+import yt
+from yt.extensions.astro_analysis.halo_analysis import HaloCatalog
+
+import yt_idv
+from yt_idv.scene_components.particles import ParticleRendering
+from yt_idv.scene_data.particle_positions import ParticlePositions
+
+# ds = yt.load_sample("Enzo_64")
+ds = yt.load("Enzo_64/DD0025/data0025")
+
+hc = HaloCatalog(data_ds=ds, finder_method="fof")
+hc.create()
+
+# set the halo file to load
+files = os.listdir(hc.output_dir)
+files.sort()
+for fi in files:
+    if hc.output_basename in fi:
+        halo_file = os.path.join(hc.output_dir, fi)
+
+# loaded as
+ds_halos = yt.load(halo_file)
+
+
+dd = ds_halos.all_data()
+
+print(dd.quantities.extrema(("halos", "virial_radius")))
+rc = yt_idv.render_context(height=800, width=800, gui=True)
+sg = rc.add_scene(ds, "density", no_ghost=True)
+sg.components[0].colormap.colormap_name = "pixel_blue.cmyt"
+
+pos = ParticlePositions(
+    data_source=dd,
+    radius_field="virial_radius",
+    particle_type="halos",
+    # color_field="virial_radius",
+    position_field="particle_position",
+)
+# pren.max_particle_size = 0.000000001
+pren: ParticleRendering = ParticleRendering(
+    data=pos,
+    scale=1.0,
+)
+pren.max_particle_size = 1e3
+sg.data_objects.append(pos)
+sg.components.append(pren)
+
+print(sg.camera.near_plane, sg.camera.far_plane)
+rc.run()