use new affine stuff in map

agb-fixnum/src/lib.rs

@@ -688,6 +688,17 @@ impl<I: FixedWidthUnsignedInteger, const N: usize> Vector2D<Num<I, N>> {
             y: self.y.floor(),
         }
     }
+
+    #[must_use]
+    /// Attempts to change the base returning None if the numbers cannot be represented
+    pub fn try_change_base<J: FixedWidthUnsignedInteger + TryFrom<I>, const M: usize>(
+        self,
+    ) -> Option<Vector2D<Num<J, M>>> {
+        Some(Vector2D::new(
+            self.x.try_change_base()?,
+            self.y.try_change_base()?,
+        ))
+    }
 }
 
 impl<const N: usize> Vector2D<Num<i32, N>> {

agb/examples/affine_background.rs

@@ -3,6 +3,7 @@
 
 use agb::{
     display::{
+        affine::{AffineMatrix, AffineMatrixBackground},
         tiled::{AffineBackgroundSize, TileFormat, TileSet, TiledMap},
         Priority,
     },
@@ -32,8 +33,8 @@ fn main(mut gba: agb::Gba) -> ! {
     bg.commit(&mut vram);
     bg.show();
 
-    let mut rotation: Num<u16, 8> = num!(0.);
-    let rotation_increase = num!(1.);
+    let mut rotation = num!(0.);
+    let rotation_increase: Num<i32, 16> = num!(0.01);
 
     let mut input = agb::input::ButtonController::new();
 
@@ -45,14 +46,19 @@ fn main(mut gba: agb::Gba) -> ! {
         scroll_x += input.x_tri() as i32;
         scroll_y += input.y_tri() as i32;
 
-        let scroll_pos = (scroll_x as i16, scroll_y as i16);
-        bg.set_scroll_pos(scroll_pos.into());
-        bg.set_transform((0, 0), (1, 1), rotation);
+        let scroll_pos = (scroll_x, scroll_y).into();
 
         rotation += rotation_increase;
-        if rotation >= num!(255.) {
-            rotation = 0.into();
-        }
+        rotation = rotation.rem_euclid(1.into());
+
+        let transformation = AffineMatrixBackground::from_scale_rotation_position(
+            (0, 0).into(),
+            (1, 1).into(),
+            rotation,
+            scroll_pos,
+        );
+
+        bg.set_transform(transformation);
 
         vblank.wait_for_vblank();
         bg.commit(&mut vram);

agb/src/display/affine.rs

@@ -62,7 +62,7 @@ impl AffineMatrix {
     #[must_use]
     /// Generates the matrix that represents a rotation
     pub fn from_rotation<const N: usize>(angle: Num<i32, N>) -> Self {
-        fn from_rotation(angle: Num<i32, 28>) -> AffineMatrix {
+        fn from_rotation(angle: Num<i32, 8>) -> AffineMatrix {
             let cos = angle.cos().change_base();
             let sin = angle.sin().change_base();
 
@@ -71,8 +71,8 @@ impl AffineMatrix {
             // space rather than how you might conventionally think of it.
             AffineMatrix {
                 a: cos,
-                b: sin,
-                c: -sin,
+                b: -sin,
+                c: sin,
                 d: cos,
                 x: 0.into(),
                 y: 0.into(),
@@ -90,15 +90,15 @@ impl AffineMatrix {
             b: 0.into(),
             c: 0.into(),
             d: 1.into(),
-            x: position.x,
-            y: position.y,
+            x: -position.x,
+            y: -position.y,
         }
     }
 
     #[must_use]
     /// The position fields of the matrix
     pub fn position(&self) -> Vector2D<Num<i32, 8>> {
-        (self.x, self.y).into()
+        (-self.x, -self.y).into()
     }
 
     /// Attempts to convert the matrix to one which can be used in affine
@@ -150,6 +150,20 @@ impl AffineMatrix {
             d: Num::from_raw(self.d.to_raw() as i16),
         }
     }
+
+    #[must_use]
+    /// Creates an affine matrix from a given (x, y) scaling. This will scale by
+    /// the inverse, ie (2, 2) will produce half the size.
+    pub fn from_scale(scale: Vector2D<Num<i32, 8>>) -> AffineMatrix {
+        AffineMatrix {
+            a: scale.x,
+            b: 0.into(),
+            c: 0.into(),
+            d: scale.y,
+            x: 0.into(),
+            y: 0.into(),
+        }
+    }
 }
 
 impl Default for AffineMatrix {
@@ -198,6 +212,35 @@ impl AffineMatrixBackground {
             y: self.y,
         }
     }
+
+    #[must_use]
+    /// Creates a transformation matrix using GBA specific syscalls.
+    /// This can be done using the standard transformation matricies like
+    ///
+    /// ```rust,no_run
+    /// use agb::display::affine::AffineMatrix;
+    /// # #![no_std]
+    /// # #![no_main]
+    /// # fn something() {
+    /// let A = AffineMatrix::from_translation(-transform_origin)
+    ///     * AffineMatrix::from_scale(scale)
+    ///     * AffineMatrix::from_rotation(rotation)
+    ///     * AffineMatrix::from_translation(position);
+    /// # }
+    /// ```
+    pub fn from_scale_rotation_position(
+        transform_origin: Vector2D<Num<i32, 8>>,
+        scale: Vector2D<Num<i32, 8>>,
+        rotation: Num<i32, 16>,
+        position: Vector2D<Num<i32, 8>>,
+    ) -> Self {
+        crate::syscall::bg_affine_matrix(
+            transform_origin,
+            position.try_change_base::<i16, 8>().unwrap().floor(),
+            scale.try_change_base().unwrap(),
+            rotation.rem_euclid(1.into()).try_change_base().unwrap(),
+        )
+    }
 }
 
 impl From<AffineMatrixBackground> for AffineMatrix {

agb/src/display/tiled/map.rs

@@ -344,16 +344,8 @@ impl AffineMap {
         *self.tiles_dirty() = true;
     }
 
-    pub fn set_transform(
-        &mut self,
-        transform_origin: impl Into<Vector2D<Num<i32, 8>>>,
-        scale: impl Into<Vector2D<Num<i16, 8>>>,
-        rotation: impl Into<Num<u16, 8>>,
-    ) {
-        let scale = scale.into();
-        let rotation = rotation.into();
-        self.transform =
-            crate::syscall::bg_affine_matrix(transform_origin.into(), self.scroll, scale, rotation);
+    pub fn set_transform(&mut self, transformation: impl Into<AffineMatrixBackground>) {
+        self.transform = transformation.into();
     }
 
     fn bg_affine_matrix(&self) -> MemoryMapped<AffineMatrixBackground> {

agb/src/syscall.rs

@@ -145,20 +145,26 @@ pub fn bg_affine_matrix(
     bg_center: Vector2D<Num<i32, 8>>,
     display_center: Vector2D<i16>,
     scale: Vector2D<Num<i16, 8>>,
-    rotation: Num<u16, 8>,
+    rotation: Num<u16, 16>,
 ) -> AffineMatrixBackground {
     #[repr(C, packed(4))]
     struct Input {
-        bg_center: Vector2D<Num<i32, 8>>,
-        display_center: Vector2D<i16>,
-        scale: Vector2D<Num<i16, 8>>,
-        rotation: Num<u16, 8>,
+        bg_center_x: Num<i32, 8>,
+        bg_center_y: Num<i32, 8>,
+        display_center_x: i16,
+        display_center_y: i16,
+        scale_x: Num<i16, 8>,
+        scale_y: Num<i16, 8>,
+        rotation: Num<u16, 16>,
     }
 
     let input = Input {
-        bg_center,
-        display_center,
-        scale,
+        bg_center_x: bg_center.x,
+        bg_center_y: bg_center.y,
+        display_center_x: display_center.x,
+        display_center_y: display_center.y,
+        scale_x: scale.x,
+        scale_y: scale.y,
         rotation,
     };