48 lines
1.1 KiB
C++

/*
* Copyright 2016 - 2021 Gary Talent (gary@drinkingtea.net). All rights reserved.
*/
// NOTE: this file is compiled as ARM and not THUMB, so don't but too much in
// here
#include <ox/std/bit.hpp>
#include "addresses.hpp"
#include "gfx.hpp"
#include "irq.hpp"
namespace nostalgia::core {
volatile uint16_t g_spriteUpdates = 0;
GbaSpriteAttrUpdate g_spriteBuffer[config::GbaSpriteBufferLen];
volatile gba_timer_t g_timerMs = 0;
}
using namespace nostalgia::core;
extern "C" {
void nostalgia_core_isr_vblank() {
// copy g_spriteUpdates to allow it to use a register instead of reading
// from memory every iteration of the loop, needed because g_spriteUpdates
// is volatile
const unsigned updates = g_spriteUpdates;
for (unsigned i = 0; i < updates; ++i) {
const auto &oa = g_spriteBuffer[i];
MEM_OAM[oa.idx] = *reinterpret_cast<const uint64_t*>(&oa);
}
g_spriteUpdates = 0;
if constexpr(config::GbaEventLoopTimerBased) {
// disable vblank interrupt until it is needed again
REG_IE = REG_IE & ~Int_vblank;
}
}
void nostalgia_core_isr_timer0() {
g_timerMs = g_timerMs + 1;
}
}