Use numpy for transformations

svglab/attrparse/d.py

@@ -61,7 +61,7 @@ class ClosePath(_PathCommandBase):
 class LineTo(_HasEnd, _PhysicalPathCommand):
     end: point.Point
 
-    def __rmatmul__(self, other: transform.SupportsToMatrix) -> Self:
+    def __rmatmul__(self, other: transform.TransformFunction) -> Self:
         return type(self)(end=other @ self.end)
 
 
@@ -79,11 +79,11 @@ def __rmatmul__(
     ) -> Self: ...
 
     @overload
-    def __rmatmul__(self, other: transform.SupportsToMatrix) -> Self: ...
+    def __rmatmul__(self, other: transform.TransformFunction) -> Self: ...
 
     @override
     def __rmatmul__(
-        self, other: transform.SupportsToMatrix
+        self, other: transform.TransformFunction
     ) -> Self | LineTo:
         if isinstance(other, transform.Translate | transform.Scale):
             x, _ = other @ point.Point(self.x, 0)
@@ -107,11 +107,11 @@ def __rmatmul__(
     ) -> Self: ...
 
     @overload
-    def __rmatmul__(self, other: transform.SupportsToMatrix) -> Self: ...
+    def __rmatmul__(self, other: transform.TransformFunction) -> Self: ...
 
     @override
     def __rmatmul__(
-        self, other: transform.SupportsToMatrix
+        self, other: transform.TransformFunction
     ) -> Self | LineTo:
         if isinstance(other, transform.Translate | transform.Scale):
             _, y = other @ point.Point(0, self.y)
@@ -126,7 +126,7 @@ def __rmatmul__(
 class SmoothQuadraticBezierTo(_HasEnd, _PhysicalPathCommand):
     end: point.Point
 
-    def __rmatmul__(self, other: transform.SupportsToMatrix) -> Self:
+    def __rmatmul__(self, other: transform.TransformFunction) -> Self:
         return type(self)(end=other @ self.end)
 
 
@@ -136,7 +136,7 @@ class SmoothCubicBezierTo(_HasEnd, _PhysicalPathCommand):
     control2: point.Point
     end: point.Point
 
-    def __rmatmul__(self, other: transform.SupportsToMatrix) -> Self:
+    def __rmatmul__(self, other: transform.TransformFunction) -> Self:
         return type(self)(
             control2=other @ self.control2, end=other @ self.end
         )
@@ -147,7 +147,7 @@ def __rmatmul__(self, other: transform.SupportsToMatrix) -> Self:
 class MoveTo(_HasEnd, _PhysicalPathCommand):
     end: point.Point
 
-    def __rmatmul__(self, other: transform.SupportsToMatrix) -> Self:
+    def __rmatmul__(self, other: transform.TransformFunction) -> Self:
         return type(self)(end=other @ self.end)
 
 
@@ -157,7 +157,7 @@ class QuadraticBezierTo(_HasEnd, _PhysicalPathCommand):
     control: point.Point
     end: point.Point
 
-    def __rmatmul__(self, other: transform.SupportsToMatrix) -> Self:
+    def __rmatmul__(self, other: transform.TransformFunction) -> Self:
         return type(self)(
             control=other @ self.control, end=other @ self.end
         )
@@ -170,7 +170,7 @@ class CubicBezierTo(_HasEnd, _PhysicalPathCommand):
     control2: point.Point
     end: point.Point
 
-    def __rmatmul__(self, other: transform.SupportsToMatrix) -> Self:
+    def __rmatmul__(self, other: transform.TransformFunction) -> Self:
         return type(self)(
             control1=other @ self.control1,
             control2=other @ self.control2,
@@ -187,17 +187,29 @@ class ArcTo(_HasEnd, _PhysicalPathCommand):
     sweep: bool
     end: point.Point
 
-    def __rmatmul__(self, other: transform.SupportsToMatrix) -> Self:
-        # right now, the radii are not transformed; this is incorrect
-        # TODO: figure out how to transform the radii
-        # (probably by converting to center parameterization, applying the
-        # transform, then converting back to endpoint parameterization)
+    def __rmatmul__(self, other: transform.TransformFunction) -> Self:
+        radii = self.radii
+        angle = self.angle
+        end = self.end
+
+        match other:
+            case transform.Translate():
+                end = other @ end
+            case transform.Scale():
+                radii = other @ radii
+                end = other @ end
+            case transform.Rotate(a):
+                angle += a
+            case _:
+                msg = f"Unsupported transform: {type(other)}"
+                raise TypeError(msg)
+
         return type(self)(
-            radii=self.radii,
-            angle=self.angle,
+            radii=radii,
+            angle=angle,
             large=self.large,
             sweep=self.sweep,
-            end=other @ self.end,
+            end=end,
         )
 
 
@@ -899,7 +911,7 @@ def __len__(self) -> int:
         return len(self.__commands)
 
     @override
-    def __rmatmul__(self, other: transform.SupportsToMatrix) -> Self:
+    def __rmatmul__(self, other: transform.TransformFunction) -> Self:
         return type(self)(
             other @ command
             for command in self

svglab/attrparse/point.py

@@ -3,6 +3,8 @@
 from collections.abc import Iterator
 
 import lark
+import numpy as np
+import numpy.typing as npt
 import pydantic
 from typing_extensions import (
     Annotated,
@@ -13,16 +15,17 @@
     override,
 )
 
-from svglab import mixins, protocols, serialize, utils
-from svglab.attrparse import parse
+from svglab import mixins, protocols, serialize, utils, utiltypes
+from svglab.attrparse import parse, transform
 
 
 @pydantic.dataclasses.dataclass(frozen=True)
 class _Point(
     SupportsComplex,
     mixins.FloatMulDiv,
-    mixins.AddSub["_Point"],
+    transform.PointAddSubWithTranslateRMatmul,
     protocols.PointLike,
+    protocols.SupportsNpArray,
     protocols.CustomSerializable,
 ):
     """A point in a 2D plane.
@@ -100,17 +103,59 @@ def line_reflect(self, center: Self) -> Self:
         """
         return center + (center - self)
 
+    @override
+    @override
+    def __array__(
+        self, dtype: npt.DTypeLike = None, *, copy: bool | None = None
+    ) -> utiltypes.NpFloatArray:
+        del dtype, copy
+
+        return np.array([self.x, self.y, 1])
+
+    @classmethod
+    def from_array(cls, array: utiltypes.NpFloatArray, /) -> Self:
+        """Create a `Point` instance from a NumPy array.
+
+        The array must be a 3-element vector, representing a cartesian point
+        in the real projective plane using homogeneous coordinates.
+
+        The last element of the array must be non-zero (i.e., the point must
+        not be at infinity).
+
+        Args:
+            array: The array to convert to a point.
+
+        Returns:
+            The point represented by the array.
+
+        Raises:
+            ValueError: If the array is not a 3-element vector or if the last
+                element of the array is zero.
+
+        """
+        if array.shape != (3,):
+            raise ValueError("The array must be a 3-element vector")
+
+        x, y, z = array
+
+        try:
+            return cls(x / z, y / z)
+        except ZeroDivisionError as e:
+            # if z is zero, the point is at infinity
+            raise ValueError(
+                "The last element of the array cannot be zero"
+            ) from e
+
     def __iter__(self) -> Iterator[float]:
         return iter((self.x, self.y))
 
-    @override
-    def __add__(self, other: Self) -> Self:
-        return type(self)(self.x + other.x, self.y + other.y)
-
     @override
     def __mul__(self, scalar: float) -> Self:
         return type(self)(self.x * scalar, self.y * scalar)
 
+    def __rmatmul__(self, other: protocols.SupportsNpArray) -> Self:
+        return self.from_array(np.array(other) @ np.array(self))
+
     @override
     def __eq__(self, other: object) -> bool:
         if not utils.basic_compare(other, self=self):