Gameboy Development Forum

Ah! So right now my game loop looks like this

while (true)
{
    WaitForVBLANK();
    PollJoypadInput();
    UpdatePlayer();
    UpdateEnemies();
    TransferDataToOAM();
}

I was always under the mindset that I had to wait for VBLANK until I could run my code, but instead I could wait for an arbitrary scanline, let's say number 100
and then I could make my loop look something like this:

while (true)
{
    WaitForLine100();
    PollJoypadInput();
    UpdatePlayer();
    UpdateEnemies();
   
    WaitForVBLANK();
    TransferDataToOAM();
}

And now I split up the code into two sections; first section updates the internal RAM and then second updates VRAM. And now I have 44 scanlines worth of time before VBLANK that I can update game logic like player collisions and stuff.
Wow this is much, much better!

I guess another way of rearranging the game loop is like this:

while (true)
{
    WaitForVBLANK();
    TransferDataToOAM();
    PollJoypadInput();
    UpdatePlayer();
    UpdateEnemies();
}

But then it takes almost a whole frame of time until the graphics are updated from the players input. But this is another possible solution. I don't think 1/60th of a second of input lag would be noticeable at all.

Thank you for the help Tag!