Simplify and standardise formatting of geometry types

src/base/matrix.rs

@@ -1968,6 +1968,21 @@ impl_fmt!(fmt::UpperHex, "{:X}", "{:1$X}");
 impl_fmt!(fmt::Binary, "{:b}", "{:.1$b}");
 impl_fmt!(fmt::Pointer, "{:p}", "{:.1$p}");
 
+/// Displays a vector using commas as the delimiter
+pub fn display_column_vec_as_row<T: Scalar + fmt::Display, D: crate::DimName>(vector: &OVector<T, D>, f: &mut fmt::Formatter<'_>) -> fmt::Result
+where
+    DefaultAllocator: Allocator<T, D>,
+{
+    write!(f, "[")?;
+    let mut it = vector.iter();
+    std::fmt::Display::fmt(it.next().unwrap(), f)?;
+    for comp in it {
+        write!(f, ", ")?;
+        std::fmt::Display::fmt(comp, f)?;
+    }
+    write!(f, "]")
+}
+
 #[cfg(test)]
 mod tests {
     #[test]

src/geometry/dual_quaternion.rs

@@ -951,25 +951,12 @@ impl<T: RealField> Default for UnitDualQuaternion<T> {
 
 impl<T: RealField + fmt::Display> fmt::Display for UnitDualQuaternion<T> {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        if let Some(axis) = self.rotation().axis() {
+        write!(f, "{{ translation: ")?;
-            let axis = axis.into_inner();
+        crate::display_column_vec_as_row(&self.translation().vector, f)?;
-            write!(
+        write!(f, ", ")?;
-                f,
+        write!(f, "rotation: ")?;
-                "UnitDualQuaternion translation: {} − angle: {} − axis: ({}, {}, {})",
+        std::fmt::Display::fmt(&self.rotation(), f)?;
-                self.translation().vector,
+        write!(f, " }}")
-                self.rotation().angle(),
-                axis[0],
-                axis[1],
-                axis[2]
-            )
-        } else {
-            write!(
-                f,
-                "UnitDualQuaternion translation: {} − angle: {} − axis: (undefined)",
-                self.translation().vector,
-                self.rotation().angle()
-            )
-        }
     }
 }
 

src/geometry/isometry.rs

@@ -548,11 +548,11 @@ where
     R: fmt::Display,
 {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        let precision = f.precision().unwrap_or(3);
+        write!(f, "{{ translation: ")?;
-
+        crate::display_column_vec_as_row(&self.translation.vector, f)?;
-        writeln!(f, "Isometry {{")?;
+        write!(f, ", ")?;
-        write!(f, "{:.*}", precision, self.translation)?;
+        write!(f, "rotation: ")?;
-        write!(f, "{:.*}", precision, self.rotation)?;
+        std::fmt::Display::fmt(&self.rotation, f)?;
-        writeln!(f, "}}")
+        write!(f, " }}")
     }
 }

src/geometry/point.rs

@@ -35,7 +35,7 @@ use std::mem::MaybeUninit;
 /// may have some other methods, e.g., `isometry.inverse_transform_point(&point)`. See the documentation
 /// of said transformations for details.
 #[repr(C)]
-#[derive(Clone)]
+#[derive(Clone, Debug)]
 #[cfg_attr(
     feature = "rkyv-serialize-no-std",
     derive(rkyv::Archive, rkyv::Serialize, rkyv::Deserialize)
@@ -49,15 +49,6 @@ where
     pub coords: OVector<T, D>,
 }
 
-impl<T: Scalar + fmt::Debug, D: DimName> fmt::Debug for OPoint<T, D>
-where
-    DefaultAllocator: Allocator<T, D>,
-{
-    fn fmt(&self, formatter: &mut fmt::Formatter<'_>) -> Result<(), fmt::Error> {
-        self.coords.as_slice().fmt(formatter)
-    }
-}
-
 impl<T: Scalar + hash::Hash, D: DimName> hash::Hash for OPoint<T, D>
 where
     DefaultAllocator: Allocator<T, D>,
@@ -457,17 +448,19 @@ impl<T: Scalar + fmt::Display, D: DimName> fmt::Display for OPoint<T, D>
 where
     DefaultAllocator: Allocator<T, D>,
 {
+    /// ```rust
+    /// # use nalgebra::Point3;
+    /// let point = Point3::new(1.12345678, 2.12345678, 3.12345678);
+    /// let rounded = format!("{:#.4}", point); // print point in compact representation
+    /// assert_eq!(rounded, "[1.1235, 2.1235, 3.1235]");
+    /// let vertical = format!("{}", point); // print point as a column
+    /// assert_eq!(vertical, "\n  ┌            ┐\n  │ 1.12345678 │\n  │ 2.12345678 │\n  │ 3.12345678 │\n  └            ┘");
+    /// ```
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        write!(f, "{{")?;
+        if f.alternate() {
-
+            crate::display_column_vec_as_row(&self.coords, f)
-        let mut it = self.coords.iter();
+        } else {
-
+            std::fmt::Display::fmt(&self.coords, f) // pretty-prints vector
-        write!(f, "{}", *it.next().unwrap())?;
+        }
-
-        for comp in it {
-            write!(f, ", {}", *comp)?;
-        }
-
-        write!(f, "}}")
     }
 }

src/geometry/quaternion.rs

@@ -36,7 +36,13 @@ pub struct Quaternion<T> {
 
 impl<T: fmt::Debug> fmt::Debug for Quaternion<T> {
     fn fmt(&self, formatter: &mut fmt::Formatter<'_>) -> Result<(), fmt::Error> {
-        self.coords.as_slice().fmt(formatter)
+        formatter
+            .debug_struct("Quaternion")
+            .field("x", &self.coords[0])
+            .field("y", &self.coords[1])
+            .field("z", &self.coords[2])
+            .field("w", &self.coords[3])
+            .finish()
     }
 }
 
@@ -995,11 +1001,16 @@ impl<T: RealField + UlpsEq<Epsilon = T>> UlpsEq for Quaternion<T> {
 
 impl<T: RealField + fmt::Display> fmt::Display for Quaternion<T> {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        write!(
+        // Formatting of each item is forwarded to standard fmt display so that formatting
-            f,
+        // flags are followed correctly.
-            "Quaternion {} − ({}, {}, {})",
+        std::fmt::Display::fmt(&self[0], f)?;
-            self[3], self[0], self[1], self[2]
+        write!(f, " + ")?;
-        )
+        std::fmt::Display::fmt(&self[1], f)?;
+        write!(f, "i + ")?;
+        std::fmt::Display::fmt(&self[2], f)?;
+        write!(f, "j + ")?;
+        std::fmt::Display::fmt(&self[3], f)?;
+        write!(f, "k")
     }
 }
 
@@ -1636,23 +1647,22 @@ impl<T: RealField> Default for UnitQuaternion<T> {
 
 impl<T: RealField + fmt::Display> fmt::Display for UnitQuaternion<T> {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        // Formatting of each item is forwarded to standard fmt Display so that formatting
+        // flags are followed correctly.
+        write!(f, "{{ angle: ")?;
+        std::fmt::Display::fmt(&self.angle(), f)?;
+        write!(f, ", axis: (")?;
         if let Some(axis) = self.axis() {
             let axis = axis.into_inner();
-            write!(
+            std::fmt::Display::fmt(&axis[0], f)?;
-                f,
+            write!(f, ", ")?;
-                "UnitQuaternion angle: {} − axis: ({}, {}, {})",
+            std::fmt::Display::fmt(&axis[1], f)?;
-                self.angle(),
+            write!(f, ", ")?;
-                axis[0],
+            std::fmt::Display::fmt(&axis[2], f)?;
-                axis[1],
-                axis[2]
-            )
         } else {
-            write!(
+            write!(f, "undefined")?;
-                f,
-                "UnitQuaternion angle: {} − axis: (undefined)",
-                self.angle()
-            )
         }
+        write!(f, ") }}")
     }
 }
 

src/geometry/scale.rs

@@ -23,19 +23,13 @@ use crate::geometry::Point;
     derive(rkyv::Archive, rkyv::Serialize, rkyv::Deserialize)
 )]
 #[cfg_attr(feature = "cuda", derive(cust_core::DeviceCopy))]
-#[derive(Copy, Clone)]
+#[derive(Copy, Clone, Debug)]
 pub struct Scale<T, const D: usize> {
     /// The scale coordinates, i.e., how much is multiplied to a point's coordinates when it is
     /// scaled.
     pub vector: SVector<T, D>,
 }
 
-impl<T: fmt::Debug, const D: usize> fmt::Debug for Scale<T, D> {
-    fn fmt(&self, formatter: &mut fmt::Formatter<'_>) -> Result<(), fmt::Error> {
-        self.vector.as_slice().fmt(formatter)
-    }
-}
-
 impl<T: Scalar + hash::Hash, const D: usize> hash::Hash for Scale<T, D>
 where
     Owned<T, Const<D>>: hash::Hash,
@@ -369,10 +363,10 @@ where
  */
 impl<T: Scalar + fmt::Display, const D: usize> fmt::Display for Scale<T, D> {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        let precision = f.precision().unwrap_or(3);
+        if f.alternate() {
-
+            crate::display_column_vec_as_row(&self.vector, f)
-        writeln!(f, "Scale {{")?;
+        } else {
-        write!(f, "{:.*}", precision, self.vector)?;
+            std::fmt::Display::fmt(&self.vector, f) // pretty-prints vector
-        writeln!(f, "}}")
+        }
     }
 }

src/geometry/similarity.rs

@@ -397,11 +397,13 @@ where
     R: AbstractRotation<T, D> + fmt::Display,
 {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        let precision = f.precision().unwrap_or(3);
+        write!(f, "{{ translation: ")?;
-
+        crate::display_column_vec_as_row(&self.isometry.translation.vector, f)?;
-        writeln!(f, "Similarity {{")?;
+        write!(f, ", ")?;
-        write!(f, "{:.*}", precision, self.isometry)?;
+        write!(f, "rotation: ")?;
-        write!(f, "Scaling: {:.*}", precision, self.scaling)?;
+        std::fmt::Display::fmt(&self.isometry.rotation, f)?;
-        writeln!(f, "}}")
+        write!(f, ", scaling: ")?;
+        std::fmt::Display::fmt(&self.scaling, f)?;
+        write!(f, " }}")
     }
 }

src/geometry/translation.rs

@@ -23,19 +23,13 @@ use crate::geometry::Point;
     derive(rkyv::Archive, rkyv::Serialize, rkyv::Deserialize)
 )]
 #[cfg_attr(feature = "cuda", derive(cust_core::DeviceCopy))]
-#[derive(Copy, Clone)]
+#[derive(Copy, Clone, Debug)]
 pub struct Translation<T, const D: usize> {
     /// The translation coordinates, i.e., how much is added to a point's coordinates when it is
     /// translated.
     pub vector: SVector<T, D>,
 }
 
-impl<T: fmt::Debug, const D: usize> fmt::Debug for Translation<T, D> {
-    fn fmt(&self, formatter: &mut fmt::Formatter<'_>) -> Result<(), fmt::Error> {
-        self.vector.as_slice().fmt(formatter)
-    }
-}
-
 impl<T: Scalar + hash::Hash, const D: usize> hash::Hash for Translation<T, D>
 where
     Owned<T, Const<D>>: hash::Hash,
@@ -284,10 +278,10 @@ where
  */
 impl<T: Scalar + fmt::Display, const D: usize> fmt::Display for Translation<T, D> {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        let precision = f.precision().unwrap_or(3);
+        if f.alternate() {
-
+            crate::display_column_vec_as_row(&self.vector, f)
-        writeln!(f, "Translation {{")?;
+        } else {
-        write!(f, "{:.*}", precision, self.vector)?;
+            std::fmt::Display::fmt(&self.vector, f) // pretty-prints vector
-        writeln!(f, "}}")
+        }
     }
 }