From 6b6a0717c25743de4cd2ed94b73d318dca3edeb1 Mon Sep 17 00:00:00 2001
From: Dzmitry Malyshau <kvark@mozilla.com>
Date: Tue, 25 Jul 2017 12:27:18 -0400
Subject: [PATCH] Mint matrices

---
 src/core/conversion.rs   | 55 +++++++++++++++++++++++++++++++++++++++-
 tests/core/conversion.rs | 30 +++++++++++++++++++++-
 2 files changed, 83 insertions(+), 2 deletions(-)

diff --git a/src/core/conversion.rs b/src/core/conversion.rs
index 247a7ee5..34486c4a 100644
--- a/src/core/conversion.rs
+++ b/src/core/conversion.rs
@@ -280,8 +280,61 @@ macro_rules! impl_from_into_mint_1D(
 
 // Implement for vectors of dimension 2 .. 4.
 #[cfg(feature = "mint")]
-impl_from_into_mint_1D!(    // Column vectors.
+impl_from_into_mint_1D!(
     U2 => Vector2[2];
     U3 => Vector3[3];
     U4 => Vector4[4];
 );
+
+#[cfg(feature = "mint")]
+macro_rules! impl_from_into_mint_2D(
+    ($(($NRows: ty, $NCols: ty) => $MV:ident{ $($component:ident),* }[$SZRows: expr]);* $(;)*) => {$(
+        impl<N, S> From<mint::$MV<N>> for Matrix<N, $NRows, $NCols, S>
+        where N: Scalar,
+              S: OwnedStorage<N, $NRows, $NCols>,
+              S::Alloc: OwnedAllocator<N, $NRows, $NCols, S> {
+            #[inline]
+            fn from(m: mint::$MV<N>) -> Self {
+                unsafe {
+                    let mut res = Self::new_uninitialized();
+                    let mut ptr = res.data.ptr_mut();
+                    $(
+                        ptr::copy_nonoverlapping(&m.$component.x, ptr, $SZRows);
+                        ptr = ptr.offset($SZRows);
+                    )*
+                    let _ = ptr;
+                    res
+                }
+            }
+        }
+
+        impl<N, S> Into<mint::$MV<N>> for Matrix<N, $NRows, $NCols, S>
+        where N: Scalar,
+              S: OwnedStorage<N, $NRows, $NCols>,
+              S::Alloc: OwnedAllocator<N, $NRows, $NCols, S> {
+            #[inline]
+            fn into(self) -> mint::$MV<N> {
+                unsafe {
+                    let mut res: mint::$MV<N> = mem::uninitialized();
+                    let mut ptr = self.data.ptr();
+                    $(
+                        ptr::copy_nonoverlapping(ptr, &mut res.$component.x, $SZRows);
+                        ptr = ptr.offset($SZRows);
+                    )*
+                    let _ = ptr;
+                    res
+                }
+            }
+        }
+    )*}
+);
+
+// Implement for matrices with shape 2x2 .. 4x4.
+#[cfg(feature = "mint")]
+impl_from_into_mint_2D!(
+    (U2, U2) => ColumnMatrix2{x, y}[2];
+    (U3, U2) => ColumnMatrix3x2{x, y}[3];
+    (U3, U3) => ColumnMatrix3{x, y, z}[3];
+    (U4, U3) => ColumnMatrix4x3{x, y, z}[4];
+    (U4, U4) => ColumnMatrix4{x, y, z, w}[4];
+);
diff --git a/tests/core/conversion.rs b/tests/core/conversion.rs
index ca6d23cf..355dcb14 100644
--- a/tests/core/conversion.rs
+++ b/tests/core/conversion.rs
@@ -267,8 +267,8 @@ macro_rules! mint_vector_conversion(
             let mv: mint::$Vector<usize> = v.into();
             let mv_ref: &mint::$Vector<usize> = v.as_ref();
             let v2      = $Vector::from(mv);
-
             let arr: [usize; $SZ] = mv.into();
+
             for i in 0 .. $SZ {
                 assert_eq!(arr[i], i);
             }
@@ -300,3 +300,31 @@ fn mint_quaternion_conversions() {
 
     assert_eq!(q, q2);
 }
+
+macro_rules! mint_matrix_conversion(
+    ($($mint_matrix_conversion_i_j: ident, $Matrix: ident, $Mint: ident, ($NRows: expr, $NCols: expr));* $(;)*) => {$(
+        #[test]
+        fn $mint_matrix_conversion_i_j() {
+            let m       = $Matrix::from_fn(|i, j| i * 10 + j);
+            let mm: mint::$Mint<usize> = m.into();
+            let m2      = $Matrix::from(mm);
+            let arr: [[usize; $NRows]; $NCols] = mm.into();
+
+            for i in 0 .. $NRows {
+                for j in 0 .. $NCols {
+                    assert_eq!(arr[j][i], i * 10 + j);
+                }
+            }
+
+            assert_eq!(m, m2);
+        }
+    )*}
+);
+
+mint_matrix_conversion!(
+    mint_matrix_conversion_2_2, Matrix2,   ColumnMatrix2,   (2, 2);
+    mint_matrix_conversion_3_2, Matrix3x2, ColumnMatrix3x2, (3, 2);
+    mint_matrix_conversion_3_3, Matrix3,   ColumnMatrix3,   (3, 3);
+    mint_matrix_conversion_4_3, Matrix4x3, ColumnMatrix4x3, (4, 3);
+    mint_matrix_conversion_4_4, Matrix4,   ColumnMatrix4,   (4, 4);
+);