Add support for colouring by quantitative colour legend, not just qualitative categories

src/bonsai/bonsai/bim/module/search/operator.py

@@ -18,15 +18,16 @@
 
 import bpy
 import json
+import bisect
 import ifcopenshell
 import ifcopenshell.api
 import ifcopenshell.guid
 import ifcopenshell.util.element
 import ifcopenshell.util.selector
 import bonsai.tool as tool
-from bonsai.bim.ifc import IfcStore
 import bonsai.core.search as core
-from itertools import cycle
+from bonsai.bim.ifc import IfcStore
+from natsort import natsorted
 from bpy.types import PropertyGroup, Operator
 from bpy.props import (
     PointerProperty,
@@ -40,22 +41,6 @@ from bpy.props import (
 )
 
 
-colour_list = [
-    (0.651, 0.81, 0.892, 1),
-    (0.121, 0.471, 0.706, 1),
-    (0.699, 0.876, 0.54, 1),
-    (0.199, 0.629, 0.174, 1),
-    (0.983, 0.605, 0.602, 1),
-    (0.89, 0.101, 0.112, 1),
-    (0.989, 0.751, 0.427, 1),
-    (0.986, 0.497, 0.1, 1),
-    (0.792, 0.699, 0.839, 1),
-    (0.414, 0.239, 0.603, 1),
-    (0.993, 0.999, 0.6, 1),
-    (0.693, 0.349, 0.157, 1),
-]
-
-
 class AddFilterGroup(Operator):
     bl_idname = "bim.add_filter_group"
     bl_label = "Add Filter Group"
@@ -270,27 +255,74 @@ class ColourByProperty(Operator):
             self.report({"ERROR"}, "No Query Provided")
             return {"CANCELLED"}
 
-        colours = cycle(colour_list)
+        is_qualitative = props.pallette in ("tab10", "paired")
+
+        if is_qualitative:
+            colours = tool.Search.get_qualitative_pallette(props.pallette)
+
         colourscheme = {}
 
-        if len(props.colourscheme):
+        obj_values = {}
+        min_value = None
+        max_value = None
+
+        if is_qualitative and len(props.colourscheme):
             colourscheme = {cs.name: {"colour": cs.colour[0:3], "total": 0} for cs in props.colourscheme}
 
         for obj in context.visible_objects:
             element = tool.Ifc.get_entity(obj)
             if not element:
                 continue
-            value = str(ifcopenshell.util.selector.get_element_value(element, query))
-            if value in colourscheme:
-                colourscheme[value]["total"] += 1
+            value = ifcopenshell.util.selector.get_element_value(element, query)
+            if is_qualitative:
+                value = str(value)
+                if value in colourscheme:
+                    colourscheme[value]["total"] += 1
+                else:
+                    colourscheme[value] = {"colour": next(colours)[0:3], "total": 1}
+                obj.color = (*colourscheme[value]["colour"], 1)
             else:
-                colourscheme[value] = {"colour": next(colours)[0:3], "total": 1}
-            obj.color = (*colourscheme[value]["colour"], 1)
+                if value is None:
+                    obj.color = (0, 0, 0, 1)
+                    if "None" in colourscheme:
+                        colourscheme["None"]["total"] += 1
+                    else:
+                        colourscheme["None"] = {"colour": (0, 0, 0), "total": 1}
+                else:
+                    try:
+                        value = float(value)
+                        if min_value is None or value < min_value:
+                            min_value = value
+                        if max_value is None or value > max_value:
+                            max_value = value
+                        obj_values[obj] = value
+                    except:
+                        obj.color = (0, 0, 0, 1)
+
+        if not is_qualitative:
+            steps = 10
+            step_size = (max_value - min_value) / (steps - 1)
+            values = []
+            for i in range(steps):
+                step_value = min_value + i * step_size
+                values.append(step_value)
+                colourscheme[str(step_value)] = {
+                    "colour": tool.Search.get_quantitative_pallette("foo", step_value, min_value, max_value),
+                    "total": 0,
+                }
+
+            for obj, value in obj_values.items():
+                index = bisect.bisect_right(values, value)
+                if index >= len(values):
+                    index = -1
+                colourscheme[str(values[index])]["total"] += 1
+                obj.color = (*tool.Search.get_quantitative_pallette("foo", value, min_value, max_value), 1)
+
         if areas := [a for a in context.screen.areas if a.type == "VIEW_3D"]:
             areas[0].spaces[0].shading.color_type = "OBJECT"
 
         props.colourscheme.clear()
-        for value in sorted(colourscheme.keys()):
+        for value in natsorted(colourscheme.keys()):
             data = colourscheme[value]
             new = props.colourscheme.add()
             new.name = str(value)
@@ -331,13 +363,40 @@ class SelectByProperty(Operator):
 
         active_value = props.colourscheme[props.active_colourscheme_index].name
 
+        is_qualitative = props.pallette in ("tab10", "paired")
+
+        if not is_qualitative:
+            values = []
+            for colour in props.colourscheme:
+                try:
+                    values.append(float(colour.name))
+                except:
+                    pass
+            values = sorted(values)
+
         for obj in context.visible_objects:
             element = tool.Ifc.get_entity(obj)
             if not element:
                 continue
-            value = str(ifcopenshell.util.selector.get_element_value(element, query))
-            if value == active_value:
-                obj.select_set(True)
+            value = ifcopenshell.util.selector.get_element_value(element, query)
+            if is_qualitative:
+                if str(value) == active_value:
+                    obj.select_set(True)
+            else:
+                if active_value == "None":
+                    if value is None:
+                        obj.select_set(True)
+                else:
+                    try:
+                        value = float(value)
+                        index = bisect.bisect_right(values, value)
+                        if index >= len(values):
+                            index = -1
+                        if values[index] == float(active_value):
+                            obj.select_set(True)
+                    except:
+                        pass
+
         return {"FINISHED"}
 
 

src/bonsai/bonsai/bim/module/search/prop.py

@@ -123,6 +123,15 @@ class BIMSearchProperties(PropertyGroup):
     saved_searches: EnumProperty(items=get_saved_searches, name="Saved Searches")
     saved_colourschemes: EnumProperty(items=get_saved_colourschemes, name="Saved Colourschemes")
     colourscheme_query: StringProperty(name="Colourscheme Query", default="class")
+    pallette: EnumProperty(
+        items=[
+            ("tab10", "Default", "Contrasting colours to distinguish categories"),
+            ("paired", "Paired", "Pairs of colours to distinguish categories"),
+            ("coolwarm", "CoolWarm", "A diverging linear range from blue to red with white in the middle"),
+            ("spectral", "Spectral", "A diverging spectral range from red to blue with white in the middle"),
+        ],
+        name="Pallette",
+    )
     colourscheme: CollectionProperty(type=BIMColour)
     active_colourscheme_index: IntProperty(name="Active Colourscheme Index")
     filter_type: StringProperty(name="Filter Type")

src/bonsai/bonsai/bim/module/search/ui.py

@@ -85,6 +85,9 @@ class BIM_PT_colour_by_property(Panel):
         row = self.layout.row()
         row.prop(props, "colourscheme_query", text="Query")
 
+        row = self.layout.row()
+        row.prop(props, "pallette")
+
         row = self.layout.row(align=True)
         row.operator("bim.colour_by_property", icon="BRUSH_DATA")
         row.operator("bim.reset_object_colours")

src/bonsai/bonsai/tool/search.py

@@ -4,6 +4,7 @@ import lark
 import bonsai.core.tool
 import ifcopenshell.guid
 import ifcopenshell.util.selector
+from itertools import cycle
 from bonsai.bim.prop import BIMFacet
 from typing import Union, Literal
 
@@ -113,6 +114,70 @@ class Search(bonsai.core.tool.Search):
             return value
         return '"' + value.replace('"', '\\"') + '"'
 
+    @classmethod
+    def get_qualitative_pallette(cls, theme: str = "tab10") -> cycle:
+        if theme == "paired":
+            pass
+        return cycle(
+            [
+                (0.651, 0.81, 0.892, 1),
+                (0.121, 0.471, 0.706, 1),
+                (0.699, 0.876, 0.54, 1),
+                (0.199, 0.629, 0.174, 1),
+                (0.983, 0.605, 0.602, 1),
+                (0.89, 0.101, 0.112, 1),
+                (0.989, 0.751, 0.427, 1),
+                (0.986, 0.497, 0.1, 1),
+                (0.792, 0.699, 0.839, 1),
+                (0.414, 0.239, 0.603, 1),
+                (0.993, 0.999, 0.6, 1),
+                (0.693, 0.349, 0.157, 1),
+            ]
+        )
+
+    @classmethod
+    def interpolate_color(cls, c1, c2, factor):
+        return tuple((1 - factor) * x + factor * y for x, y in zip(c1, c2))
+
+    @classmethod
+    def get_quantitative_pallette(cls, theme: str, value, min_val, max_val):
+        palette = [
+            (0.227, 0.298, 0.753),
+            (0.282, 0.376, 0.820),
+            (0.345, 0.463, 0.886),
+            (0.412, 0.545, 0.937),
+            (0.482, 0.620, 0.973),
+            (0.553, 0.686, 0.992),
+            (0.616, 0.741, 0.996),
+            (0.686, 0.792, 0.984),
+            (0.753, 0.827, 0.961),
+            (0.812, 0.851, 0.918),
+            (0.865, 0.863, 0.863),
+            (0.910, 0.835, 0.792),
+            (0.945, 0.792, 0.714),
+            (0.965, 0.737, 0.635),
+            (0.965, 0.671, 0.553),
+            (0.957, 0.604, 0.482),
+            (0.929, 0.518, 0.404),
+            (0.890, 0.424, 0.329),
+            (0.839, 0.322, 0.263),
+            (0.773, 0.196, 0.200),
+            (0.702, 0.012, 0.149),
+        ]
+
+        if value < min_val:
+            value = min_val
+        if value > max_val:
+            value = max_val
+
+        scale = (value - min_val) / (max_val - min_val) * (len(palette) - 1)
+        index = int(scale)
+        fraction = scale - index
+
+        if index >= len(palette) - 1:
+            return palette[-1]
+        return cls.interpolate_color(palette[index], palette[index + 1], fraction)
+
 
 class ImportFilterQueryTransformer(lark.Transformer):
     def __init__(self, filter_groups):