add priority

agb/src/display/mod.rs

@@ -111,3 +111,10 @@ pub fn busy_wait_for_VBlank() {
     while VCOUNT.get() >= 160 {}
     while VCOUNT.get() < 160 {}
 }
+
+pub enum Priority {
+    P0 = 0,
+    P1 = 1,
+    P2 = 2,
+    P3 = 3,
+}

agb/src/display/object.rs

@@ -1,6 +1,6 @@
 use core::cell::RefCell;
 
-use super::DISPLAY_CONTROL;
+use super::{Priority, DISPLAY_CONTROL};
 use crate::bitarray::Bitarray;
 use crate::memory_mapped::MemoryMapped1DArray;
 use crate::number::Vector2D;
@@ -124,6 +124,10 @@ impl ObjectStandard<'_> {
         self.attributes.set_x(x);
         self.attributes.set_y(y);
     }
+
+    pub fn set_priority(&mut self, p: Priority) {
+        self.attributes.set_priority(p)
+    }
 }
 
 impl<'a> ObjectAffine<'a> {
@@ -176,6 +180,10 @@ impl<'a> ObjectAffine<'a> {
         self.attributes.set_x(x);
         self.attributes.set_y(y);
     }
+
+    pub fn set_priority(&mut self, p: Priority) {
+        self.attributes.set_priority(p)
+    }
 }
 
 fn set_bits(current: u16, value: u16, length: u16, shift: u16) -> u16 {
@@ -254,6 +262,10 @@ impl ObjectAttribute {
     fn set_affine(&mut self, aff_id: u8) {
         self.a1 = set_bits(self.a1, aff_id as u16, 5, 0x9);
     }
+
+    fn set_priority(&mut self, p: Priority) {
+        self.a2 = set_bits(self.a2, p as u16, 2, 0x0A);
+    }
 }
 
 impl AffineMatrix<'_> {

agb/src/display/tiled0.rs

@@ -6,7 +6,7 @@ use crate::{
 };
 
 use super::{
-    palette16, set_graphics_mode, set_graphics_settings, DisplayMode, GraphicsSettings,
+    palette16, set_graphics_mode, set_graphics_settings, DisplayMode, GraphicsSettings, Priority,
     DISPLAY_CONTROL,
 };
 
@@ -22,13 +22,6 @@ const TILE_SPRITE: MemoryMapped1DArray<u32, { 512 * 8 }> =
 
 const MAP: *mut [[[u16; 32]; 32]; 32] = 0x0600_0000 as *mut _;
 
-pub enum Prioriry {
-    P0 = 0,
-    P1 = 1,
-    P2 = 2,
-    P3 = 3,
-}
-
 pub enum ColourMode {
     FourBitPerPixel = 0,
     EightBitPerPixel = 1,
@@ -101,7 +94,7 @@ impl Background {
 
     /// Sets priority of the background layer. Backgrounds with higher priority
     /// are drawn (above/below) backgrounds with lower priority.
-    pub fn set_priority(&mut self, p: Prioriry) {
+    pub fn set_priority(&mut self, p: Priority) {
         unsafe { self.set_bits(0, 2, p as u16) }
     }