diff options
| -rw-r--r-- | src/devices/screen_device.rs | 19 |
1 files changed, 17 insertions, 2 deletions
diff --git a/src/devices/screen_device.rs b/src/devices/screen_device.rs index b4eae22..a10ab20 100644 --- a/src/devices/screen_device.rs +++ b/src/devices/screen_device.rs @@ -419,6 +419,7 @@ impl HasDimensions<u16> for ScreenDevice { pub struct SpriteBuffer { pub mem: [u8; 16], pub pointer: usize, + pub cached: Option<(Sprite, u8)>, } impl SpriteBuffer { @@ -426,15 +427,22 @@ impl SpriteBuffer { Self { mem: [0; 16], pointer: 0, + cached: None, } } pub fn push_byte(&mut self, byte: u8) { self.mem[self.pointer] = byte; self.pointer = (self.pointer + 1) % 16; + self.cached = None; } - pub fn read_1bit_sprite(&self, draw: u8) -> Sprite { + pub fn read_1bit_sprite(&mut self, draw: u8) -> Sprite { + if let Some((sprite, transform)) = self.cached { + if transform == (draw & 0x77) { + return sprite; + } + } macro_rules! c { ($v:ident=mem[$p:ident++]) => { let $v = self.mem[$p % 16]; $p = $p.wrapping_add(1); }; ($v:ident=mem[--$p:ident]) => { $p = $p.wrapping_sub(1); let $v = self.mem[$p % 16]; }; @@ -455,10 +463,16 @@ impl SpriteBuffer { 0x7 => { for y in 0..8 { c!(l=mem[--p]); for x in 0..8 { sprite[x][y] = l>>( x) & 1; } } }, _ => unreachable!(), } + self.cached = Some((sprite, draw & 0x77)); return sprite; } - pub fn read_2bit_sprite(&self, draw: u8) -> Sprite { + pub fn read_2bit_sprite(&mut self, draw: u8) -> Sprite { + if let Some((sprite, transform)) = self.cached { + if transform == (draw & 0x77) { + return sprite; + } + } macro_rules! c { ($v:ident=mem[$p:ident++]) => { let $v = self.mem[$p % 16]; $p = $p.wrapping_add(1); }; ($v:ident=mem[--$p:ident]) => { $p = $p.wrapping_sub(1); let $v = self.mem[$p % 16]; }; @@ -480,6 +494,7 @@ impl SpriteBuffer { 0x7 => for y in 0..8 { c!(l=mem[--p]); c!(h=mem[--s]); for x in 0..8 { let i= x; sprite[x][y] = (l>>i & 1) | (h>>i & 1) << 1; } }, _ => unreachable!(), } + self.cached = Some((sprite, draw & 0x77)); return sprite; } } |