Refactor ROM class; introduce snes.h for address conversion utilities, enhancing code organization and maintainability.

src/app/snes.h

@@ -0,0 +1,51 @@
+#ifndef YAZE_SNES_H_
+#define YAZE_SNES_H_
+
+#include <cstdint>
+
+namespace yaze {
+
+inline uint32_t SnesToPc(uint32_t addr) noexcept {
+  constexpr uint32_t kFastRomRegion = 0x808000;
+  if (addr >= kFastRomRegion) {
+    addr -= kFastRomRegion;
+  }
+  uint32_t temp = (addr & 0x7FFF) + ((addr / 2) & 0xFF8000);
+  return (temp + 0x0);
+}
+
+inline uint32_t PcToSnes(uint32_t addr) {
+  uint8_t* b = reinterpret_cast<uint8_t*>(&addr);
+  b[2] = static_cast<uint8_t>(b[2] * 2);
+
+  if (b[1] >= 0x80) {
+    b[2] += 1;
+  } else {
+    b[1] += 0x80;
+  }
+
+  return addr;
+}
+
+inline uint32_t Get24LocalFromPC(uint8_t* data, int addr, bool pc = true) {
+  uint32_t ret =
+      (PcToSnes(addr) & 0xFF0000) | (data[addr + 1] << 8) | data[addr];
+  if (pc) {
+    return SnesToPc(ret);
+  }
+  return ret;
+}
+
+inline int AddressFromBytes(uint8_t bank, uint8_t high, uint8_t low) noexcept {
+  return (bank << 16) | (high << 8) | low;
+}
+
+inline uint32_t MapBankToWordAddress(uint8_t bank, uint16_t addr) noexcept {
+  uint32_t result = 0;
+  result = (bank << 16) | addr;
+  return result;
+}
+
+}  // namespace yaze
+
+#endif  // YAZE_SNES_H_