DPI version 0.1.0

The conversion of PhysicalUnit was wrongly computed and the tests were
not running on the CI for the dpi crate, thus it was missed, even though
the test was correctly failing.

Signed-off-by: John Nunley <dev@notgull.net>
Signed-off-by: Kirill Chibisov <contact@kchibisov.com>

.github/workflows/ci.yml

@@ -145,6 +145,13 @@ jobs:
     - name: Build crate
       run: cargo $CMD build $OPTIONS
 
+    # Test only on Linux x86_64, so we avoid spending unnecessary CI hours.
+    - name: Test dpi crate
+      if: >
+        contains(matrix.platform.name, 'Linux 64bit') &&
+        matrix.toolchain != '1.70.0'
+      run: cargo test -p dpi
+
     - name: Build tests
       if: >
         !contains(matrix.platform.target, 'redox') &&

CHANGELOG.md

@@ -51,6 +51,7 @@ Unreleased` header.
 - **Breaking:** Removed `EventLoopBuilder::with_user_event`, the functionality is now available in `EventLoop::with_user_event`.
 - Add `Window::default_attributes` to get default `WindowAttributes`.
 - `log` has been replaced with `tracing`. The old behavior can be emulated by setting the `log` feature on the `tracing` crate.
+- On X11, fix crash due to xsettings query on systems with incomplete xsettings.
 
 # 0.29.14
 

dpi/CHANGELOG.md

@@ -0,0 +1,16 @@
+# Changelog
+
+All notable changes to this project will be documented in this file.
+
+Please keep one empty line before and after all headers. (This is required for
+`git` to produce a conflict when a release is made while a PR is open and the
+PR's changelog entry would go into the wrong section).
+
+And please only add new entries to the top of this list, right below the `#
+Unreleased` header.
+
+# Unreleased
+
+# 0.1.0
+
+- Add `LogicalUnit`, `PhysicalUnit` and `PixelUnit` types and related functions.

dpi/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "dpi"
-version = "0.0.0"
+version = "0.1.0"
 description = "Types for handling UI scaling"
 keywords = ["DPI", "HiDPI", "scale-factor"]
 categories = ["gui"]

dpi/src/lib.rs

@@ -35,8 +35,8 @@
 //!
 //! ### Position and Size types
 //!
-//! The [`PhysicalPosition`] / [`PhysicalSize`] types correspond with the actual pixels on the
-//! device, and the [`LogicalPosition`] / [`LogicalSize`] types correspond to the physical pixels
+//! The [`PhysicalPosition`] / [`PhysicalSize`] / [`PhysicalUnit`] types correspond with the actual pixels on the
+//! device, and the [`LogicalPosition`] / [`LogicalSize`] / [`LogicalUnit`] types correspond to the physical pixels
 //! divided by the scale factor.
 //!
 //! The position and size types are generic over their exact pixel type, `P`, to allow the
@@ -128,6 +128,238 @@ pub fn validate_scale_factor(scale_factor: f64) -> bool {
     scale_factor.is_sign_positive() && scale_factor.is_normal()
 }
 
+/// A logical pixel unit.
+#[derive(Debug, Copy, Clone, Eq, PartialEq, Ord, PartialOrd, Default, Hash)]
+#[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
+pub struct LogicalUnit<P>(pub P);
+
+impl<P> LogicalUnit<P> {
+    /// Represents a minimum logical unit of [`f64::MAX`].
+    pub const MIN: LogicalUnit<f64> = LogicalUnit::new(f64::MIN);
+    /// Represents a logical unit of `0_f64`.
+    pub const ZERO: LogicalUnit<f64> = LogicalUnit::new(0.0);
+    /// Represents a maximum logical unit that is equal to [`f64::MAX`].
+    pub const MAX: LogicalUnit<f64> = LogicalUnit::new(f64::MAX);
+
+    #[inline]
+    pub const fn new(v: P) -> Self {
+        LogicalUnit(v)
+    }
+}
+
+impl<P: Pixel> LogicalUnit<P> {
+    #[inline]
+    pub fn from_physical<T: Into<PhysicalUnit<X>>, X: Pixel>(
+        physical: T,
+        scale_factor: f64,
+    ) -> Self {
+        physical.into().to_logical(scale_factor)
+    }
+
+    #[inline]
+    pub fn to_physical<X: Pixel>(&self, scale_factor: f64) -> PhysicalUnit<X> {
+        assert!(validate_scale_factor(scale_factor));
+        PhysicalUnit::new(self.0.into() * scale_factor).cast()
+    }
+
+    #[inline]
+    pub fn cast<X: Pixel>(&self) -> LogicalUnit<X> {
+        LogicalUnit(self.0.cast())
+    }
+}
+
+impl<P: Pixel, X: Pixel> From<X> for LogicalUnit<P> {
+    fn from(v: X) -> LogicalUnit<P> {
+        LogicalUnit::new(v.cast())
+    }
+}
+
+impl<P: Pixel> From<LogicalUnit<P>> for u8 {
+    fn from(v: LogicalUnit<P>) -> u8 {
+        v.0.cast()
+    }
+}
+
+impl<P: Pixel> From<LogicalUnit<P>> for u16 {
+    fn from(v: LogicalUnit<P>) -> u16 {
+        v.0.cast()
+    }
+}
+
+impl<P: Pixel> From<LogicalUnit<P>> for u32 {
+    fn from(v: LogicalUnit<P>) -> u32 {
+        v.0.cast()
+    }
+}
+
+impl<P: Pixel> From<LogicalUnit<P>> for i8 {
+    fn from(v: LogicalUnit<P>) -> i8 {
+        v.0.cast()
+    }
+}
+
+impl<P: Pixel> From<LogicalUnit<P>> for i16 {
+    fn from(v: LogicalUnit<P>) -> i16 {
+        v.0.cast()
+    }
+}
+
+impl<P: Pixel> From<LogicalUnit<P>> for i32 {
+    fn from(v: LogicalUnit<P>) -> i32 {
+        v.0.cast()
+    }
+}
+
+impl<P: Pixel> From<LogicalUnit<P>> for f32 {
+    fn from(v: LogicalUnit<P>) -> f32 {
+        v.0.cast()
+    }
+}
+
+impl<P: Pixel> From<LogicalUnit<P>> for f64 {
+    fn from(v: LogicalUnit<P>) -> f64 {
+        v.0.cast()
+    }
+}
+
+/// A physical pixel unit.
+#[derive(Debug, Copy, Clone, Eq, PartialEq, Ord, PartialOrd, Default, Hash)]
+#[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
+pub struct PhysicalUnit<P>(pub P);
+
+impl<P> PhysicalUnit<P> {
+    /// Represents a minimum physical unit of [`f64::MAX`].
+    pub const MIN: LogicalUnit<f64> = LogicalUnit::new(f64::MIN);
+    /// Represents a physical unit of `0_f64`.
+    pub const ZERO: LogicalUnit<f64> = LogicalUnit::new(0.0);
+    /// Represents a maximum physical unit that is equal to [`f64::MAX`].
+    pub const MAX: LogicalUnit<f64> = LogicalUnit::new(f64::MAX);
+
+    #[inline]
+    pub const fn new(v: P) -> Self {
+        PhysicalUnit(v)
+    }
+}
+
+impl<P: Pixel> PhysicalUnit<P> {
+    #[inline]
+    pub fn from_logical<T: Into<LogicalUnit<X>>, X: Pixel>(logical: T, scale_factor: f64) -> Self {
+        logical.into().to_physical(scale_factor)
+    }
+
+    #[inline]
+    pub fn to_logical<X: Pixel>(&self, scale_factor: f64) -> LogicalUnit<X> {
+        assert!(validate_scale_factor(scale_factor));
+        LogicalUnit::new(self.0.into() / scale_factor).cast()
+    }
+
+    #[inline]
+    pub fn cast<X: Pixel>(&self) -> PhysicalUnit<X> {
+        PhysicalUnit(self.0.cast())
+    }
+}
+
+impl<P: Pixel, X: Pixel> From<X> for PhysicalUnit<P> {
+    fn from(v: X) -> PhysicalUnit<P> {
+        PhysicalUnit::new(v.cast())
+    }
+}
+
+impl<P: Pixel> From<PhysicalUnit<P>> for u8 {
+    fn from(v: PhysicalUnit<P>) -> u8 {
+        v.0.cast()
+    }
+}
+
+impl<P: Pixel> From<PhysicalUnit<P>> for u16 {
+    fn from(v: PhysicalUnit<P>) -> u16 {
+        v.0.cast()
+    }
+}
+
+impl<P: Pixel> From<PhysicalUnit<P>> for u32 {
+    fn from(v: PhysicalUnit<P>) -> u32 {
+        v.0.cast()
+    }
+}
+
+impl<P: Pixel> From<PhysicalUnit<P>> for i8 {
+    fn from(v: PhysicalUnit<P>) -> i8 {
+        v.0.cast()
+    }
+}
+
+impl<P: Pixel> From<PhysicalUnit<P>> for i16 {
+    fn from(v: PhysicalUnit<P>) -> i16 {
+        v.0.cast()
+    }
+}
+
+impl<P: Pixel> From<PhysicalUnit<P>> for i32 {
+    fn from(v: PhysicalUnit<P>) -> i32 {
+        v.0.cast()
+    }
+}
+
+impl<P: Pixel> From<PhysicalUnit<P>> for f32 {
+    fn from(v: PhysicalUnit<P>) -> f32 {
+        v.0.cast()
+    }
+}
+
+impl<P: Pixel> From<PhysicalUnit<P>> for f64 {
+    fn from(v: PhysicalUnit<P>) -> f64 {
+        v.0.cast()
+    }
+}
+
+/// A pixel unit that's either physical or logical.
+pub enum PixelUnit {
+    Physical(PhysicalUnit<i32>),
+    Logical(LogicalUnit<f64>),
+}
+
+impl PixelUnit {
+    /// Represents a minimum logical unit of [`f64::MAX`].
+    pub const MIN: PixelUnit = PixelUnit::Logical(LogicalUnit::new(f64::MIN));
+    /// Represents a logical unit of `0_f64`.
+    pub const ZERO: PixelUnit = PixelUnit::Logical(LogicalUnit::new(0.0));
+    /// Represents a maximum logical unit that is equal to [`f64::MAX`].
+    pub const MAX: PixelUnit = PixelUnit::Logical(LogicalUnit::new(f64::MAX));
+
+    pub fn new<S: Into<PixelUnit>>(unit: S) -> PixelUnit {
+        unit.into()
+    }
+
+    pub fn to_logical<P: Pixel>(&self, scale_factor: f64) -> LogicalUnit<P> {
+        match *self {
+            PixelUnit::Physical(unit) => unit.to_logical(scale_factor),
+            PixelUnit::Logical(unit) => unit.cast(),
+        }
+    }
+
+    pub fn to_physical<P: Pixel>(&self, scale_factor: f64) -> PhysicalUnit<P> {
+        match *self {
+            PixelUnit::Physical(unit) => unit.cast(),
+            PixelUnit::Logical(unit) => unit.to_physical(scale_factor),
+        }
+    }
+}
+
+impl<P: Pixel> From<PhysicalUnit<P>> for PixelUnit {
+    #[inline]
+    fn from(unit: PhysicalUnit<P>) -> PixelUnit {
+        PixelUnit::Physical(unit.cast())
+    }
+}
+
+impl<P: Pixel> From<LogicalUnit<P>> for PixelUnit {
+    #[inline]
+    fn from(unit: LogicalUnit<P>) -> PixelUnit {
+        PixelUnit::Logical(unit.cast())
+    }
+}
+
 /// A position represented in logical pixels.
 ///
 /// The position is stored as floats, so please be careful. Casting floats to integers truncates the
@@ -730,6 +962,43 @@ mod tests {
         assert!(!validate_scale_factor(f64::NEG_INFINITY));
     }
 
+    #[test]
+    fn test_logical_unity() {
+        let log_unit = LogicalUnit::new(1.0);
+        assert_eq!(log_unit.to_physical::<u32>(1.0), PhysicalUnit::new(1));
+        assert_eq!(log_unit.to_physical::<u32>(2.0), PhysicalUnit::new(2));
+        assert_eq!(log_unit.cast::<u32>(), LogicalUnit::new(1));
+        assert_eq!(
+            log_unit,
+            LogicalUnit::from_physical(PhysicalUnit::new(1.0), 1.0)
+        );
+        assert_eq!(
+            log_unit,
+            LogicalUnit::from_physical(PhysicalUnit::new(2.0), 2.0)
+        );
+        assert_eq!(LogicalUnit::from(2.0), LogicalUnit::new(2.0));
+
+        let x: f64 = log_unit.into();
+        assert_eq!(x, 1.0);
+    }
+
+    #[test]
+    fn test_physical_unit() {
+        assert_eq!(
+            PhysicalUnit::from_logical(LogicalUnit::new(1.0), 1.0),
+            PhysicalUnit::new(1)
+        );
+        assert_eq!(
+            PhysicalUnit::from_logical(LogicalUnit::new(2.0), 0.5),
+            PhysicalUnit::new(1)
+        );
+        assert_eq!(PhysicalUnit::from(2.0), PhysicalUnit::new(2.0,));
+        assert_eq!(PhysicalUnit::from(2.0), PhysicalUnit::new(2.0));
+
+        let x: f64 = PhysicalUnit::new(1).into();
+        assert_eq!(x, 1.0);
+    }
+
     #[test]
     fn test_logical_position() {
         let log_pos = LogicalPosition::new(1.0, 2.0);

src/cursor.rs

@@ -195,6 +195,7 @@ impl OnlyCursorImageSource {
 }
 
 /// Platforms export this directly as `PlatformCustomCursor` if they don't implement caching.
+#[allow(dead_code)]
 #[derive(Debug, Clone)]
 pub(crate) struct OnlyCursorImage(pub(crate) Arc<CursorImage>);
 

src/platform_impl/linux/x11/mod.rs

@@ -887,6 +887,9 @@ pub enum X11Error {
 
     /// Unable to parse xsettings.
     XsettingsParse(xsettings::ParserError),
+
+    /// Failed to get property.
+    GetProperty(util::GetPropertyError),
 }
 
 impl fmt::Display for X11Error {
@@ -896,6 +899,7 @@ impl fmt::Display for X11Error {
             X11Error::Connect(e) => write!(f, "X11 connection error: {}", e),
             X11Error::Connection(e) => write!(f, "X11 connection error: {}", e),
             X11Error::XidsExhausted(e) => write!(f, "XID range exhausted: {}", e),
+            X11Error::GetProperty(e) => write!(f, "Failed to get X property {}", e),
             X11Error::X11(e) => write!(f, "X11 error: {:?}", e),
             X11Error::UnexpectedNull(s) => write!(f, "Xlib function returned null: {}", s),
             X11Error::InvalidActivationToken(s) => write!(
@@ -988,6 +992,12 @@ impl From<xsettings::ParserError> for X11Error {
     }
 }
 
+impl From<util::GetPropertyError> for X11Error {
+    fn from(value: util::GetPropertyError) -> Self {
+        Self::GetProperty(value)
+    }
+}
+
 /// Type alias for a void cookie.
 type VoidCookie<'a> = x11rb::cookie::VoidCookie<'a, X11rbConnection>;
 

src/platform_impl/linux/x11/util/randr.rs

@@ -53,6 +53,7 @@ impl XConnection {
             .get_string("Xft.dpi", "")
             .and_then(|s| f64::from_str(s).ok())
     }
+
     pub fn get_output_info(
         &self,
         resources: &monitor::ScreenResources,

src/platform_impl/linux/x11/util/window_property.rs

@@ -1,13 +1,18 @@
-use super::*;
-use bytemuck::{NoUninit, Pod};
+use std::error::Error;
+use std::fmt;
 use std::sync::Arc;
 
+use bytemuck::{NoUninit, Pod};
+
 use x11rb::connection::Connection;
 use x11rb::errors::ReplyError;
 
-pub type Cardinal = u32;
+use super::*;
+
 pub const CARDINAL_SIZE: usize = mem::size_of::<u32>();
 
+pub type Cardinal = u32;
+
 #[derive(Debug, Clone)]
 pub enum GetPropertyError {
     X11rbError(Arc<ReplyError>),
@@ -15,12 +20,6 @@ pub enum GetPropertyError {
     FormatMismatch(c_int),
 }
 
-impl<T: Into<ReplyError>> From<T> for GetPropertyError {
-    fn from(e: T) -> Self {
-        Self::X11rbError(Arc::new(e.into()))
-    }
-}
-
 impl GetPropertyError {
     pub fn is_actual_property_type(&self, t: xproto::Atom) -> bool {
         if let GetPropertyError::TypeMismatch(actual_type) = *self {
@@ -31,6 +30,24 @@ impl GetPropertyError {
     }
 }
 
+impl<T: Into<ReplyError>> From<T> for GetPropertyError {
+    fn from(e: T) -> Self {
+        Self::X11rbError(Arc::new(e.into()))
+    }
+}
+
+impl fmt::Display for GetPropertyError {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        match self {
+            GetPropertyError::X11rbError(err) => err.fmt(f),
+            GetPropertyError::TypeMismatch(err) => write!(f, "type mismatch: {err}"),
+            GetPropertyError::FormatMismatch(err) => write!(f, "format mismatch: {err}"),
+        }
+    }
+}
+
+impl Error for GetPropertyError {}
+
 // Number of 32-bit chunks to retrieve per iteration of get_property's inner loop.
 // To test if `get_property` works correctly, set this to 1.
 const PROPERTY_BUFFER_SIZE: u32 = 1024; // 4k of RAM ought to be enough for anyone!

src/platform_impl/linux/x11/xsettings.rs

@@ -33,13 +33,11 @@ impl XConnection {
             .reply()?;
 
         // Read the _XSETTINGS_SETTINGS property.
-        let data: Vec<u8> = self
-            .get_property(
-                owner.owner,
-                atoms[_XSETTINGS_SETTINGS],
-                atoms[_XSETTINGS_SETTINGS],
-            )
-            .unwrap();
+        let data: Vec<u8> = self.get_property(
+            owner.owner,
+            atoms[_XSETTINGS_SETTINGS],
+            atoms[_XSETTINGS_SETTINGS],
+        )?;
 
         // Parse the property.
         let dpi_setting = read_settings(&data)?