bit-hack

#include <SDL/SDL.h>
#include <array>
#include <memory>
#include <assert.h>

namespace {
// min value
template <typename type_t>
constexpr type_t minv(type_t a, type_t b)
{

bit-hack

// ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ----
float constexpr lerp(float a0, float a1, float i) {
  return a0 + (a1 - a0) * i;
}

// ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ----
void intersect(float a0, float a1, float b0, float b1, vec2f_t &out) {
#if 1
  const float i = (a0 - b0) / (a0 - a1 - b0 + b1);

bit-hack

#include <cstdint>

namespace {
template <int hi, int lo>
constexpr uint32_t mask() {
  // hi_mask xor lo_mask
  return ((1u << hi) | ((1u << hi) - 1u)) ^ ((1u << lo) - 1u);
}

template <int hi, int lo>

bit-hack

#include <stdlib.h>

struct base_t {
  const int type;
  base_t() : type(0) {}
  base_t(int type) : type(type) {}
  virtual int call() { return 1; }
};

struct derived_t : public base_t {

bit-hack

# ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ----
# DATA TRANSFER
# ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ---- ----
#

@ MOV, Move
  / Register to Register/Memory
    % 2/12 + 4*w
    $ 1000100w | mod reg r/m
  / Register/memory to register

bit-hack

#include <stdint.h>

// operand format
enum {
    OPR_IMM = 0,
    OPR_ZP,
    OPR_ZPX,
    OPR_ZPY,
    OPR_ABS, 
    OPR_ABSX,

bit-hack

#include <stdint.h>

// fourcc function
static constexpr
uint32_t fourcc(const char (&in)[4]) {
    return ((in[0]<<24) | (in[1]<<16) | (in[3]<<8) | ' ');
}

// addressing mode types
enum {

bit-hack

/*
 * 6502 netlist and pin descriptions
 *
 * Original author: Greg James
 * Original source material: www.visual6502.org
**/

#pragma once
#include <cstdint>

bit-hack

OPCODE     MNEMONIC   OPERANDS   FLAGS      CYCLES     LENGTH

0x00       BRK                   B          7          1
0x01       ORA        (ind,X)    SZ         6          2
0x05       ORA        zpg        SZ         3          2
0x06       ASL        zpg        SZC        5          2
0x08       PHP                              3          1
0x09       ORA        #          SZ         2          2
0x0a       ASL        A          SZC        2          1
0x0d       ORA        abs        SZ         4          3

bit-hack

#pragma once
#include <cstdint>

struct xtea_t
{
  static const uint32_t _delta = 0x9E3779B9;

  typedef uint32_t key_t[4];

  template <uint32_t num_rounds>