From 314b4dd1031200e580b82235c082dac7f9395702 Mon Sep 17 00:00:00 2001
From: CAD97 <cad97@cad97.com>
Date: Mon, 5 Jul 2021 19:04:10 -0500
Subject: [PATCH] Remove scalar bound from geometry type defs

This was inconsistently applied, with some types having <T>, some having
<T: Scalar>, and some having <T: RealField>.
This unifies all types to match the convention of Matrix:
Just declare <T> at type def time, and apply bounds on impls only.

A significant advantage of this approach is const fn construction. Const
fn generics currently still can't have trait bounds, so any generic
const fn needs to only move opaque types around. Construction methods
such as new_unchecked or from_parts can be made const by removing their
generic bounds after this PR.

Actual constification is left to a follow-up PR.

Note that na::Transform is _not_ loosened here, as it has more complicated
definition requirements.
---
 src/geometry/dual_quaternion.rs | 13 +++++++++++--
 src/geometry/isometry.rs        |  2 +-
 src/geometry/orthographic.rs    |  2 +-
 src/geometry/perspective.rs     |  4 ++--
 src/geometry/reflection.rs      |  4 ++--
 src/geometry/rotation.rs        |  2 +-
 src/geometry/similarity.rs      |  2 +-
 7 files changed, 19 insertions(+), 10 deletions(-)

diff --git a/src/geometry/dual_quaternion.rs b/src/geometry/dual_quaternion.rs
index 63148836..17533dfb 100644
--- a/src/geometry/dual_quaternion.rs
+++ b/src/geometry/dual_quaternion.rs
@@ -38,14 +38,23 @@ use simba::scalar::{ClosedNeg, RealField};
 ///  If a feature that you need is missing, feel free to open an issue or a PR.
 ///  See https://github.com/dimforge/nalgebra/issues/487
 #[repr(C)]
-#[derive(Debug, Eq, PartialEq, Copy, Clone)]
-pub struct DualQuaternion<T: Scalar> {
+#[derive(Debug, Copy, Clone)]
+pub struct DualQuaternion<T> {
     /// The real component of the quaternion
     pub real: Quaternion<T>,
     /// The dual component of the quaternion
     pub dual: Quaternion<T>,
 }
 
+impl<T: Scalar + Eq> Eq for DualQuaternion<T> {}
+
+impl<T: Scalar> PartialEq for DualQuaternion<T> {
+    #[inline]
+    fn eq(&self, right: &Self) -> bool {
+        self.real == right.real && self.dual == right.dual
+    }
+}
+
 impl<T: Scalar + Zero> Default for DualQuaternion<T> {
     fn default() -> Self {
         Self {
diff --git a/src/geometry/isometry.rs b/src/geometry/isometry.rs
index 7d8c6e95..4e6c15d7 100755
--- a/src/geometry/isometry.rs
+++ b/src/geometry/isometry.rs
@@ -68,7 +68,7 @@ use crate::geometry::{AbstractRotation, Point, Translation};
                        DefaultAllocator: Allocator<T, Const<D>>,
                        Owned<T, Const<D>>: Deserialize<'de>"))
 )]
-pub struct Isometry<T: Scalar, R, const D: usize> {
+pub struct Isometry<T, R, const D: usize> {
     /// The pure rotational part of this isometry.
     pub rotation: R,
     /// The pure translational part of this isometry.
diff --git a/src/geometry/orthographic.rs b/src/geometry/orthographic.rs
index 17a5b969..36c6ae7f 100644
--- a/src/geometry/orthographic.rs
+++ b/src/geometry/orthographic.rs
@@ -18,7 +18,7 @@ use crate::base::{Matrix4, Vector, Vector3};
 use crate::geometry::{Point3, Projective3};
 
 /// A 3D orthographic projection stored as a homogeneous 4x4 matrix.
-pub struct Orthographic3<T: RealField> {
+pub struct Orthographic3<T> {
     matrix: Matrix4<T>,
 }
 
diff --git a/src/geometry/perspective.rs b/src/geometry/perspective.rs
index 6ad9707f..5c849a60 100644
--- a/src/geometry/perspective.rs
+++ b/src/geometry/perspective.rs
@@ -14,12 +14,12 @@ use simba::scalar::RealField;
 
 use crate::base::dimension::U3;
 use crate::base::storage::Storage;
-use crate::base::{Matrix4, Scalar, Vector, Vector3};
+use crate::base::{Matrix4, Vector, Vector3};
 
 use crate::geometry::{Point3, Projective3};
 
 /// A 3D perspective projection stored as a homogeneous 4x4 matrix.
-pub struct Perspective3<T: Scalar> {
+pub struct Perspective3<T> {
     matrix: Matrix4<T>,
 }
 
diff --git a/src/geometry/reflection.rs b/src/geometry/reflection.rs
index dcc754c2..51ee4e45 100644
--- a/src/geometry/reflection.rs
+++ b/src/geometry/reflection.rs
@@ -1,5 +1,5 @@
 use crate::base::constraint::{AreMultipliable, DimEq, SameNumberOfRows, ShapeConstraint};
-use crate::base::{Const, Matrix, Scalar, Unit, Vector};
+use crate::base::{Const, Matrix, Unit, Vector};
 use crate::dimension::{Dim, U1};
 use crate::storage::{Storage, StorageMut};
 use simba::scalar::ComplexField;
@@ -7,7 +7,7 @@ use simba::scalar::ComplexField;
 use crate::geometry::Point;
 
 /// A reflection wrt. a plane.
-pub struct Reflection<T: Scalar, D: Dim, S: Storage<T, D>> {
+pub struct Reflection<T, D, S> {
     axis: Vector<T, D, S>,
     bias: T,
 }
diff --git a/src/geometry/rotation.rs b/src/geometry/rotation.rs
index f3127fb9..3e74af65 100755
--- a/src/geometry/rotation.rs
+++ b/src/geometry/rotation.rs
@@ -55,7 +55,7 @@ use crate::geometry::Point;
 ///
 #[repr(C)]
 #[derive(Debug)]
-pub struct Rotation<T: Scalar, const D: usize> {
+pub struct Rotation<T, const D: usize> {
     matrix: SMatrix<T, D, D>,
 }
 
diff --git a/src/geometry/similarity.rs b/src/geometry/similarity.rs
index 48ce6a85..6ae79c81 100755
--- a/src/geometry/similarity.rs
+++ b/src/geometry/similarity.rs
@@ -39,7 +39,7 @@ use crate::geometry::{AbstractRotation, Isometry, Point, Translation};
                        DefaultAllocator: Allocator<T, Const<D>>,
                        Owned<T, Const<D>>: Deserialize<'de>"))
 )]
-pub struct Similarity<T: Scalar, R, const D: usize> {
+pub struct Similarity<T, R, const D: usize> {
     /// The part of this similarity that does not include the scaling factor.
     pub isometry: Isometry<T, R, D>,
     scaling: T,