create grids without copying data

crates/servicepoint/src/bitmap.rs

@@ -72,8 +72,8 @@ impl Bitmap {
     /// - when the width is not dividable by 8
     #[must_use]
     pub fn load(width: usize, height: usize, data: &[u8]) -> Self {
-        assert_eq!(width % 8, 0);
-        assert_eq!(data.len(), height * width / 8);
+        assert_eq!(width % 8, 0, "width must be a multiple of 8, but is {width}");
+        assert_eq!(data.len(), height * width / 8, "data length must match dimensions, with 8 pixels per byte.");
         Self {
             width,
             height,
@@ -81,6 +81,23 @@ impl Bitmap {
         }
     }
 
+    /// Creates a [Bitmap] with the specified width from the provided [BitVec] without copying it.
+    ///
+    /// returns: [Bitmap] that contains the provided data.
+    ///
+    /// # Panics
+    ///
+    /// - when the bitvec size is not dividable by the provided width
+    /// - when the width is not dividable by 8
+    #[must_use]
+    pub fn from_bitvec(width: usize, bit_vec: BitVec) -> Self {
+        assert_eq!(width % 8, 0, "width must be a multiple of 8, but is {width}");
+        let len = bit_vec.len();
+        let height = len / width;
+        assert_eq!(0, len % width, "dimension mismatch - len {len} is not dividable by {width}");
+        Self { width, height, bit_vec }
+    }
+
     /// Iterate over all cells in [Bitmap].
     ///
     /// Order is equivalent to the following loop:

crates/servicepoint/src/brightness_grid.rs

@@ -26,7 +26,7 @@ impl BrightnessGrid {
 }
 
 impl From<BrightnessGrid> for Vec<u8> {
-    fn from(value: ValueGrid<Brightness>) -> Self {
+    fn from(value: BrightnessGrid) -> Self {
         value
             .iter()
             .map(|brightness| (*brightness).into())
@@ -35,7 +35,7 @@ impl From<BrightnessGrid> for Vec<u8> {
 }
 
 impl From<&BrightnessGrid> for ByteGrid {
-    fn from(value: &ValueGrid<Brightness>) -> Self {
+    fn from(value: &BrightnessGrid) -> Self {
         let u8s = value
             .iter()
             .map(|brightness| (*brightness).into())

crates/servicepoint/src/command.rs

@@ -1,6 +1,5 @@
 use crate::command_code::CommandCode;
 use crate::compression::into_decompressed;
-use crate::value_grid::ValueGrid;
 use crate::*;
 
 /// Type alias for documenting the meaning of the u16 in enum values
@@ -441,7 +440,7 @@ impl Command {
             payload,
         } = packet;
 
-        let grid = ValueGrid::load(*width as usize, *height as usize, payload);
+        let grid = ByteGrid::load(*width as usize, *height as usize, payload);
         let grid = match BrightnessGrid::try_from(grid) {
             Ok(grid) => grid,
             Err(val) => return Err(TryFromPacketError::InvalidBrightness(val)),

crates/servicepoint/src/value_grid.rs

@@ -79,6 +79,21 @@ impl<T: Value> ValueGrid<T> {
         }
     }
 
+    /// Creates a [ValueGrid] with the specified width from the provided data without copying it.
+    ///
+    /// returns: [ValueGrid] that contains the provided data.
+    ///
+    /// # Panics
+    ///
+    /// - when the data size is not dividable by the width.
+    #[must_use]
+    pub fn from_vec(width: usize, data: Vec<T>) -> Self {
+        let len = data.len();
+        let height = len / width;
+        assert_eq!(0, len % width, "dimension mismatch - len {len} is not dividable by {width}");
+        Self { data, width, height }        
+    }
+
     /// Loads a [ValueGrid] with the specified width from the provided data, wrapping to as many rows as needed.
     ///
     /// returns: [ValueGrid] that contains a copy of the provided data or [TryLoadValueGridError].