do some cycle counting

Author: kirjavascript

tests/src/cycle_count.rs

@@ -0,0 +1,32 @@
+use crate::{util, score, labels};
+
+pub fn count_cycles() {
+    let mut emu = util::emulator(None);
+
+    let completed_lines = labels::get("completedLines") as usize;
+    let add_points = labels::get("addPointsRaw");
+    let level_number = labels::get("levelNumber") as usize;
+
+    let mut score = move |score: u32, lines: u8, level: u8| {
+        score::set(&mut emu, score);
+        emu.registers.pc = add_points;
+        emu.memory.iram_raw[completed_lines] = lines;
+        emu.memory.iram_raw[level_number] = level;
+        util::cycles_to_return(&mut emu)
+    };
+
+    let mut highest = 0;
+
+    // check every linecount on every level
+    for level in 0..=255 {
+        for lines in 0..=4 {
+            let count = score(999999, lines, level);
+
+            if count > highest {
+                highest = count;
+            }
+        }
+    }
+
+    println!("scoring routine most cycles: {}", highest);
+}

tests/src/main.rs

@@ -1,4 +1,5 @@
 mod block;
+mod cycle_count;
 mod drought;
 mod input;
 mod labels;
@@ -20,6 +21,8 @@ struct TestOptions {
     help: bool,
     #[options(help = "run tests")]
     test: bool,
+    #[options(help = "count cycles")]
+    cycles: bool,
     #[options(help = "set SPS seed", parse(try_from_str = "parse_hex"))]
     sps_seed: u32,
     #[options(help = "print SPS pieces")]
@@ -48,6 +51,11 @@ fn main() {
         println!("sps is the same!");
     }
 
+    // count cycles
+    if options.cycles {
+        cycle_count::count_cycles();
+    }
+
     // print SPS sequences
     if options.sps_qty > 0 {
         let mut blocks = sps::SPS::new();

tests/src/score.rs

@@ -51,7 +51,7 @@ pub fn test() {
     }
 
     // check tetris value from lots of scores
-    for initial_score in 999000..=1001000 {
+    for initial_score in 999499..=1000501 {
         assert_eq!(score(initial_score, 4, 18), initial_score + score_impl(4, 18));
     }
 }

tests/src/util.rs

@@ -31,6 +31,27 @@ pub fn run_to_return(emu: &mut NesState, print: bool) {
     opcodes::pop(emu);
 }
 
+pub fn cycles_to_return(emu: &mut NesState) -> u32 {
+    opcodes::push(emu, 0);
+    opcodes::push(emu, 0);
+
+    let mut cycles = 0;
+
+    loop {
+        cycles += 1;
+        emu.cycle();
+
+        if emu.registers.pc < 3 {
+            break;
+        }
+    }
+
+    opcodes::pop(emu);
+    opcodes::pop(emu);
+
+    cycles
+}
+
 pub fn print_step(emu: &mut NesState) {
     if let Some(label) = labels::from_addr(emu.registers.pc) {
         println!("{}:", label);
@@ -64,3 +85,20 @@ pub const fn _ppu_addr_to_xy(ppu_addr: u16) -> (u8, u8) {
 
     (x as _, y as _)
 }
+
+pub const fn _xy_to_ppu_addr(x: u16, y: u16) -> u16 {
+    const SCREEN_WIDTH: u16 = 256 / 8;
+    const SCREEN_HEIGHT: u16 = 240 / 8;
+
+    let offset = (y * 32) + x;
+
+    let base_address = match (x / SCREEN_WIDTH, y / SCREEN_HEIGHT) {
+        (0, 0) => 0x2000,
+        (1, 0) => 0x2400,
+        (0, 1) => 0x2800,
+        (1, 1) => 0x2C00,
+        _ => panic!("Invalid (x, y) position"),
+    };
+
+    base_address + offset
+}