Auto merge of #200 - nical:from-into, r=kvark

Implement some missing convenience traits.

Implement `From<[T; N]>` and `Into<[T; N]>` for points and vectors, Implement Hash for rects, and add some helper methods to convert transforms from and to arrays.

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Author: bors-servo

src/point.rs

@@ -327,6 +327,19 @@ impl<T: Copy+ApproxEq<T>, U> ApproxEq<Self> for TypedPoint2D<T, U> {
     }
 }
 
+impl<T: Copy, U> Into<[T; 2]> for TypedPoint2D<T, U> {
+    fn into(self) -> [T; 2] {
+        self.to_array()
+    }
+}
+
+impl<T: Copy, U> From<[T; 2]> for TypedPoint2D<T, U> {
+    fn from(array: [T; 2]) -> Self {
+        point2(array[0], array[1])
+    }
+}
+
+
 define_matrix! {
     /// A 3d Point tagged with a unit.
     pub struct TypedPoint3D<T, U> {
@@ -598,6 +611,18 @@ impl<T: Copy+ApproxEq<T>, U> ApproxEq<Self> for TypedPoint3D<T, U> {
     }
 }
 
+impl<T: Copy, U> Into<[T; 3]> for TypedPoint3D<T, U> {
+    fn into(self) -> [T; 3] {
+        self.to_array()
+    }
+}
+
+impl<T: Copy, U> From<[T; 3]> for TypedPoint3D<T, U> {
+    fn from(array: [T; 3]) -> Self {
+        point3(array[0], array[1], array[2])
+    }
+}
+
 
 pub fn point2<T: Copy, U>(x: T, y: T) -> TypedPoint2D<T, U> {
     TypedPoint2D::new(x, y)

src/rect.rs

@@ -20,6 +20,7 @@ use num_traits::NumCast;
 use serde::{Deserialize, Deserializer, Serialize, Serializer};
 use std::cmp::PartialOrd;
 use std::fmt;
+use std::hash::{Hash, Hasher};
 use std::ops::{Add, Sub, Mul, Div};
 
 /// A 2d Rectangle optionally tagged with a unit.
@@ -54,6 +55,14 @@ impl<T: Serialize, U> Serialize for TypedRect<T, U> {
     }
 }
 
+impl<T: Hash, U> Hash for TypedRect<T, U>
+{
+    fn hash<H: Hasher>(&self, h: &mut H) {
+        self.origin.hash(h);
+        self.size.hash(h);
+    }
+}
+
 impl<T: Copy, U> Copy for TypedRect<T, U> {}
 
 impl<T: Copy, U> Clone for TypedRect<T, U> {

src/transform2d.rs

@@ -79,6 +79,36 @@ impl<T: Copy, Src, Dst> TypedTransform2D<T, Src, Dst> {
         ]
     }
 
+    /// Returns an array containing this transform's 3 rows in (in row-major order)
+    /// as arrays.
+    ///
+    /// This is a convenience method to interface with other libraries like glium.
+    pub fn to_row_arrays(&self) -> [[T; 2]; 3] {
+        [
+            [self.m11, self.m12],
+            [self.m21, self.m22],
+            [self.m31, self.m32],
+        ]
+    }
+
+    /// Creates a transform from an array of 6 elements in row-major order.
+    pub fn from_row_major_array(array: [T; 6]) -> Self {
+        Self::row_major(
+            array[0], array[1],
+            array[2], array[3],
+            array[4], array[5],
+        )
+    }
+
+    /// Creates a transform from 3 rows of 2 elements (row-major order).
+    pub fn from_row_arrays(array: [[T; 2]; 3]) -> Self {
+        Self::row_major(
+            array[0][0], array[0][1],
+            array[1][0], array[1][1],
+            array[2][0], array[2][1],
+        )
+    }
+
     /// Drop the units, preserving only the numeric value.
     pub fn to_untyped(&self) -> Transform2D<T> {
         Transform2D::row_major(

src/transform3d.rs

@@ -597,7 +597,7 @@ impl<T: Copy, Src, Dst> TypedTransform3D<T, Src, Dst> {
     /// as arrays.
     ///
     /// This is a convenience method to interface with other libraries like glium.
-    pub fn to_row_arrays(&self) -> [[T; 4];4] {
+    pub fn to_row_arrays(&self) -> [[T; 4]; 4] {
         [
             [self.m11, self.m12, self.m13, self.m14],
             [self.m21, self.m22, self.m23, self.m24],
@@ -618,6 +618,26 @@ impl<T: Copy, Src, Dst> TypedTransform3D<T, Src, Dst> {
             [self.m14, self.m24, self.m34, self.m44]
         ]
     }
+
+    /// Creates a transform from an array of 16 elements in row-major order.
+    pub fn from_array(array: [T; 16]) -> Self {
+        Self::row_major(
+            array[0],  array[1],  array[2],  array[3],
+            array[4],  array[5],  array[6],  array[7],
+            array[8],  array[9],  array[10], array[11],
+            array[12], array[13], array[14], array[15],
+        )
+    }
+
+    /// Creates a transform from 4 rows of 4 elements (row-major order).
+    pub fn from_row_arrays(array: [[T; 4]; 4]) -> Self {
+        Self::row_major(
+            array[0][0], array[0][1], array[0][2], array[0][3],
+            array[1][0], array[1][1], array[1][2], array[1][3],
+            array[2][0], array[2][1], array[2][2], array[2][3],
+            array[3][0], array[3][1], array[3][2], array[3][3],
+        )
+    }
 }
 
 impl<T, Src, Dst> fmt::Debug for TypedTransform3D<T, Src, Dst>

src/vector.rs

@@ -348,6 +348,18 @@ impl<T: Copy+ApproxEq<T>, U> ApproxEq<TypedVector2D<T, U>> for TypedVector2D<T,
     }
 }
 
+impl<T: Copy, U> Into<[T; 2]> for TypedVector2D<T, U> {
+    fn into(self) -> [T; 2] {
+        self.to_array()
+    }
+}
+
+impl<T: Copy, U> From<[T; 2]> for TypedVector2D<T, U> {
+    fn from(array: [T; 2]) -> Self {
+        vec2(array[0], array[1])
+    }
+}
+
 define_matrix! {
     /// A 3d Vector tagged with a unit.
     pub struct TypedVector3D<T, U> {
@@ -675,6 +687,19 @@ impl<T: Copy+ApproxEq<T>, U> ApproxEq<TypedVector3D<T, U>> for TypedVector3D<T,
     }
 }
 
+impl<T: Copy, U> Into<[T; 3]> for TypedVector3D<T, U> {
+    fn into(self) -> [T; 3] {
+        self.to_array()
+    }
+}
+
+impl<T: Copy, U> From<[T; 3]> for TypedVector3D<T, U> {
+    fn from(array: [T; 3]) -> Self {
+        vec3(array[0], array[1], array[2])
+    }
+}
+
+
 /// Convenience constructor.
 #[inline]
 pub fn vec2<T: Copy, U>(x: T, y: T) -> TypedVector2D<T, U> {