Pull out more from graphics!

Refactor all of the color stuff into drawing/colors.py
and color_internals.py

Note drawing/color_internals.py used to be somewhat vague name
drawing/colors.py. But really it just had internal color routines.

drawing/colors.py was selected because that's what the Section name is
in WL https://reference.wolfram.com/language/guide/Colors.html and the
classes in there all into what's described there.

Down the line it would be nice to separate better externally visable
classes from all the implementaiton code that is not visiable, but
that's too big a lift for now.

Note: this started out as just an effort to document some of the
builtins that had no documentaiton.

And a little of that has been done too.

Author: rocky

mathics/builtin/box/graphics.py

@@ -11,19 +11,17 @@
     BoxConstructError,
 )
 
+from mathics.builtin.drawing.colors import _Color, ColorError, RGBColor
+from mathics.builtin.drawing.graphics_internals import _GraphicsElement, GLOBALS
+
 from mathics.builtin.graphics import (
     Arrowheads,
-    ColorError,
     Coords,
     DEFAULT_POINT_FACTOR,
-    GLOBALS,
     Graphics,
     GraphicsElements,
     PointSize,
-    RGBColor,
     _BezierCurve,
-    _Color,
-    _GraphicsElement,
     _Line,
     _Polyline,
     _data_and_options,
@@ -1176,20 +1174,19 @@ def vertices():
         super(RegularPolygonBox, self).init(graphics, style, new_item)
 
 
-GLOBALS_GRAPHICS = system_symbols_dict(
+# FIXME: GLOBALS is a horrible name.
+GLOBALS.update(
     {
-        "RectangleBox": RectangleBox,
-        "DiskBox": DiskBox,
-        "LineBox": LineBox,
-        "BezierCurveBox": BezierCurveBox,
-        "FilledCurveBox": FilledCurveBox,
-        "ArrowBox": ArrowBox,
-        "CircleBox": CircleBox,
-        "PolygonBox": PolygonBox,
-        "RegularPolygonBox": RegularPolygonBox,
-        "PointBox": PointBox,
-        "InsetBox": InsetBox,
+        "System`RectangleBox": RectangleBox,
+        "System`DiskBox": DiskBox,
+        "System`LineBox": LineBox,
+        "System`BezierCurveBox": BezierCurveBox,
+        "System`FilledCurveBox": FilledCurveBox,
+        "System`ArrowBox": ArrowBox,
+        "System`CircleBox": CircleBox,
+        "System`PolygonBox": PolygonBox,
+        "System`RegularPolygonBox": RegularPolygonBox,
+        "System`PointBox": PointBox,
+        "System`InsetBox": InsetBox,
     }
 )
-
-GLOBALS.update(GLOBALS_GRAPHICS)

mathics/builtin/box/graphics3d.py

@@ -10,23 +10,16 @@
 from mathics.builtin.base import BoxConstructError
 from mathics.builtin.box.graphics import GraphicsBox, LineBox, PointBox, PolygonBox
 
+from mathics.builtin.drawing.colors import _Color, RGBColor
+from mathics.builtin.drawing.graphics_internals import GLOBALS3D
 from mathics.builtin.drawing.graphics3d import (
     _Graphics3DElement,
     Coords3D,
     Graphics3DElements,
 )
 
-from mathics.core.expression import (
-    Symbol,
-    system_symbols_dict,
-)
-
-from mathics.builtin.graphics import (
-    RGBColor,
-    _Color,
-    get_class,
-)
-
+from mathics.builtin.drawing.graphics_internals import get_class
+from mathics.core.expression import Symbol
 from mathics.core.formatter import lookup_method
 from mathics.format.asy_fns import asy_create_pens, asy_number
 
@@ -809,11 +802,12 @@ def _apply_boxscaling(self, boxscale):
         pass
 
 
-GLOBALS3D = system_symbols_dict(
+# FIXME: GLOBALS3D is a horrible name.
+GLOBALS3D.update(
     {
-        "Polygon3DBox": Polygon3DBox,
-        "Line3DBox": Line3DBox,
-        "Point3DBox": Point3DBox,
-        "Sphere3DBox": Sphere3DBox,
+        "System`Polygon3DBox": Polygon3DBox,
+        "System`Line3DBox": Line3DBox,
+        "System`Point3DBox": Point3DBox,
+        "System`Sphere3DBox": Sphere3DBox,
     }
 )