yupferris

 - Lots of things seem to be indexed with r4; looks like it's always 0x05008000
   - This is consistent with the "global data pointer" info in the tech scroll
   - Looks like the offset into this mem is always negative

 - Known globals (as negative offsets from r4):
   -1402 (0x05007a86) - Effective OBJ group 3 ptr

Routine that hits obj group ptr's (occurs once per frame)
 - r6 = data pointer. Appears to be 0x05007a80 every time (I believe this is only called from the code below).
 - Looks like this just copies the 8 bytes starting at r6 into the OBJ group ptr reg's

yupferris

use std::io::{self, Read};
use std::fs::File;
use std::path::Path;

fn main() {
    let rom_file_name = "C:\\msys64\\home\\ferris\\dev\\projects\\vb-rs-corpus\\Mario's Tennis (Japan, USA).vb";
    let buf = load(rom_file_name).unwrap();
    let src = 0xfff9fb4c;
    let dst = 0x00078000;

yupferris

use std::io::{self, Write,  Read, BufWriter};
use std::fs::File;
use std::path::Path;

const NUM_CHANNELS: usize = 1;
const BITS_PER_SAMPLE: usize = 16;

fn main() {
    let rom_file_name = "C:\\msys64\\home\\ferris\\dev\\projects\\vb-rs-corpus\\Galactic Pinball (Japan, USA).vb";
    let buf = load(rom_file_name).unwrap();

yupferris

// Super high-level playroutine overview:
//  Timer reload set to 0x0004
//  Timer int fires every 120us (sample rate of ~8333.3hz)
//   Store 0x15 in timer control (small interval, zero interrupt disable, clear zero status, timer enable)
//   Output volumes to VOICE_1_VOLUME - VOICE_5_VOLUME
//   Store 0x19 in timer control (small interval, zero interrupt enable, timer enable)

* 0xfffffe10  7c44        add 28, r3
  0xfffffe12  23dc0000    st.w r1, 0[r3]
  0xfffffe16  20bc0207    movhi 0x702, r0, r1

yupferris

// Super high-level playroutine overview:
//  Timer reload set to 12, 13, 5 (depending on sample)
//  Timer int fires every ??us (sample rate of ??hz)
//   Store 0x1d in timer control (small interval, zero interrupt enable, clear zero status, timer enable)
//   Output volume to VOICE_1_ENVELOPE_DATA

  // Sample value -> register value lookup table:
  0xffffd258  00 10 20 30 40 50 60 70 80 90 a0 b0 c0 d0 e0 f0

  // Sample playback routine (only thing the timer is used for in this game)

yupferris

extern crate minifb;
extern crate time;

use minifb::{Key, Scale, WindowOptions, Window};

use std::f64::consts::PI;

fn circle(x: f64, y: f64, x_offset: f64, y_offset: f64, rad: f64) -> bool {
    let x_distance = x - x_offset;
    let y_distance = y - y_offset;

yupferris

// Sometime outside of display area..
VCBASE := 0
VIDEO_COLOR_BUFFER := 0

for RASTER in 0..312 {
    for line_cycle in 0..63 {
        badline_condition := (RASTER & 0x07) == (YSCROLL & 0x07)
        if (badline_condition) {
            MODE = MODE_DISPLAY
        }

yupferris

// This is kindof a crazy way to compare paths, and in certain unicode corner cases will not be entirely correct,
//  but it's a workaround for file name case insensitivity on Windows and should be good enough for most cases.
//  The general idea (matching path component suffixes) mimicks Rust's Path::ends_with.
fn ends_with_case_insensitive(path: &PathBuf, suffix: &PathBuf) -> bool {
    let path_comps = path.components().map(|x| String::from(x.as_os_str().to_string_lossy()).to_lowercase()).rev();
    let suffix_comps = suffix.components().map(|x| String::from(x.as_os_str().to_string_lossy()).to_lowercase()).rev();
    let matching_suffix_pairs = path_comps.zip(suffix_comps).filter(|&(ref x, ref y)| x == y);
    matching_suffix_pairs.count() == suffix.components().count()
}

yupferris

fn decompress(mut src: *const u8, dst: *mut u8) {
    // Skip first 2 bytes (they're always zero)
    src += 2;

    let original_dst = dst;

    // Load bytes_left
    let mut bytes_left = ((*src as i32) << 8) + 1;
    src += 1;
    bytes_left += *src as i32;

yupferris

// Super high-level playroutine overview:
//  Timer reload set to 0x0002
//  Timer int fires every ~50us (no, that's not a typo)
//   Store 0x00 in timer control (large interval, zero interrupt disable, timer disable)
//   Store 0x19 in timer control (small interval, zero interrupt enable, timer enable)
//   Output volume to VOICE_1_ENVELOPE_DATA and VOICE_2_ENVELOPE_DATA

// Data stream
// 0xXX           where 0xXX != 0x0f => envelope data <- 0xXX << 4 (reload value = 0xXX & 0x0f; count down to 0)
// 0x0f 0xXX 0xYY where 0xXX != 0x0f => voice volume <- 0xXX; envelope data <- 0xYY << 4