Add curve support

Author: carson-katri

api/node_mapper.py

@@ -6,6 +6,7 @@
 from .state import State
 from .types import *
 from .static.input_group import InputGroup
+from .static.curve import Curve
 from ..absolute_path import absolute_path
 
 class OutputsList(dict):
@@ -28,6 +29,13 @@ def build(_primary_arg=None, **kwargs):
             argname = prop.identifier.lower().replace(' ', '_')
             if argname in kwargs:
                 value = kwargs[argname]
+                if isinstance(value, list) and len(value) > 0 and isinstance(value[0], Curve):
+                    for i, curve in enumerate(value):
+                        curve.apply(getattr(node, prop.identifier).curves[i])
+                    continue
+                if isinstance(value, Curve):
+                    value.apply(getattr(node, prop.identifier).curves[0])
+                    continue
                 if isinstance(value, enum.Enum):
                     value = value.value
                 setattr(node, prop.identifier, value)

api/static/curve.py

@@ -0,0 +1,54 @@
+from typing import List
+import enum
+
+class HandleType(enum.Enum):
+    AUTO = 'AUTO'
+    VECTOR = 'VECTOR'
+    AUTO_CLAMPED = 'AUTO_CLAMPED'
+
+class Point:
+    """
+    A single point on a curve
+    """
+
+    x: float
+    y: float
+    handle_type: HandleType
+
+    def __init__(self, x: float, y: float, handle_type: HandleType = HandleType.AUTO):
+        self.x = x
+        self.y = y
+        self.handle_type = handle_type
+
+class Curve:
+    """
+    A class that represents a curve.
+
+    Create a curve from a set of `Point`s.
+    ```python
+    my_curve = Curve(
+        Point(0, 0, Handle.AUTO_CLAMPED),
+        Point(0.2, 0.3, Handle.AUTO),
+        Point(1, 1, Handle.VECTOR)
+    )
+    ```
+    """
+
+    points: List[Point]
+
+    def __init__(self, *points: Point):
+        if len(points) == 1 and isinstance(points[0], list):
+            self.points = points[0]
+        else:
+            self.points = list(points)
+
+    def apply(self, curve):
+        """
+        Apply the points to a curve object.
+        """
+        for i, point in enumerate(self.points):
+            if len(curve.points) > i:
+                curve.points[i].location = (point.x, point.y)
+                curve.points[i].handle_type = point.handle_type.value
+            else:
+                curve.points.new(point.x, point.y).handle_type = point.handle_type.value

api/tree.py

@@ -8,6 +8,7 @@
 from .types import *
 from .node_mapper import *
 from .static.attribute import *
+from .static.curve import *
 from .static.expression import *
 from .static.input_group import *
 from .static.sample_mode import *

book/src/SUMMARY.md

@@ -21,6 +21,7 @@
     - [Input Groups](./api/advanced-scripting/input-groups.md)
     - [Attributes](./api/advanced-scripting/attributes.md)
     - [Boolean Math](./api/advanced-scripting/boolean-math.md)
+    - [Curves](./api/advanced-scripting/curves.md)
     - [Drivers](./api/advanced-scripting/drivers.md)
     - [Simulation](./api/advanced-scripting/simulation.md)
 

book/src/api/advanced-scripting/curves.md

@@ -0,0 +1,32 @@
+# Curves
+
+Some nodes, such as *Float Curve* take a curve as a property. You can create a curve with the `Curve` class.
+
+```python
+float_curve(
+    mapping=Curve(
+        Point(0, 0),
+        Point(0.5, 0.25),
+        Point(1, 1, HandleType.VECTOR), # Optionally specify a handle type, such as `AUTO`, `VECTOR`, or `AUTO_CLAMPED`.
+    )
+)
+```
+
+![](./float_curve.png)
+
+You can also pass the points as a list to `Curve`.
+
+```python
+points = [Point(0, 0), Point(1, 1)]
+float_curve(
+    mapping=Curve(points)
+)
+```
+
+If a node has multiple curve properties, such as the *Vector Curves* node, pass a list of curves to the node.
+
+```python
+vector_curves(
+    mapping=[x_curve, y_curve, z_curve]
+)
+```