The glEnd() of Zelda

1 The glend () of ZeldaDr. Tom Murphy VII 1 April 2016 Abstract3D ZELDAK eywords: small keys, boss keys, dungeon keys1 Introduction1986. legend offrickin Zelda for theNintendofreakin Entertainment System. Need I saymore? Agod damngoldcartridge. Fortunes madejust from melting the gold cartridge down to make goldteeth grilles, after carefully extracting and preservingthe even more precious ROM inside. A die-cut hole inthe box so that you could get a peek of the cartridgeand presage that you were getting some solid gold. Adie cut little window that you could palpate throughthe wrapping paper on Christmas Eve, presaging someepic thumb blisters in store for the coming weeks.

2 Kojifreckin Kondo. Koji Kondo whipping up a nice 8-bitarrangement of Bol ero as the theme music until realiz-ing at the last minute that this music was copyrighted1and so instead composing its epic theme inone day??A gold cartridge that contained ROMs and a littleswallowable battery to keep the onboard SRAM pow-ered up so that it could retain your epic save game. Abattery designed to last 70 years. Nothing could causeyou to lose your save game, even once you were half waythrough the Second Quest. Unless your little brotherstarts a completely new game and saves over your slot,earning him one of the most righteously deserved clob-berings this side of Inigo Montoya.

3 Saves right on top ofyour slot with a player called justA. Right over your Copyright 2016 the Regents of the Wikiplia in SIGBOVIK 2016 with the danger of going alone of theAssociation for Computational Heresy;IEEEEEE!press, Verlag Verlag volume no. 0x2016. 255 Rupees1 Perhaps ironic, since Ravel s Bol ero itself was composed asa result of Ravel getting cop-blocked.[1] And surely some Zeldaknock-off since then has included a Muzak ersatz of the Zeldatheme! What is the longest documented sequence of compositionsdue to Copyright restrictions?

4 Figure 1: Technical diagram of mathematical , erasing it, and hasn t even picked up theswordyet. All you have to do is step on the black squarein the first room and the guy gives you the sword andthen dies. Jeez pooleaze. Saves right over yours with nosword even though there are TWO OTHER UNUSEDSLOTS and you even wisely put your game in the thirdslotexactly to avoid this kind of I say more? Shall I say it? Apparently THESE DAYS. Kids these days and their threedimensions. You can certainly make a respectable casethat the Zeldest of the series wasLegend of Zelda III: ALink To The Past, or evenLegend of Game Boy Zelda :I forgot What It s Called.

5 But there seems to be anestablished consensus thatLegend of Zelda LXIV: TheOcarina of Timeis the true masterpiece; that while theNES Original indeed invented the genre, the technicallimitations of the system handicapped it. You re talkingto me about technicalfrockin limitations? Like some-how appreciating the subtle wonder of the universe andits mechanics requires me to look at 3D tree people withtetrahedric clubs for hands. And they say this of the64thgame in the series? Please fine game, don t get me wrong. But was its themesong composed in one day?

6 Did it come in a gold car-tridge?And the thing is: The original Zelda was built withenough forethought that itcanbe rendered in first-person 3D. So here I will make the game 3D so thatit can be enjoyed by these kids and they can get off mylawn, tapdancing around playing their titular will make it possible to play the game in glorious HD,or even 4K resolution, and then some (Figure 1). Andwhile we re at it, why not try to do it in a way that canplay loads of NES games in threefr ockin dimensions?What s the worst that could happen?

7 2 Technical limitationsAs presaged, the NES does have certain technical limi-tations, which I prefer to think of as constraints. Somebasic details are important for understanding how NES has a modest CPU that executes game s a little 8-bit baby puppy with access to 2 kilobytesof RAM. If you think about it, the NES s 256x240 pixelscreen is already 61,440 pixels, which if it used the entire2k of RAM to represent it, we d have only bits ofRAM per pixel, which makes no sense. At MhZ,and a generous 1 instruction per pixel, we d only beable to render 28 frames per second!

8 This doesn t makesense, and this is because the CPU does not render thegraphics on a NES also contains a custom Picture Process-ing Unit, or PPU, the 8-bit baby puppy s baby ppupybrother. This thing outputs 60 frames of NTSC videoper second. In fact, since the PPU also drives a CPUinterrupt for each scanline and vblank, and most gamesFigure 2: Pattern tables for the Zelda overworld. InZelda, the top tiles are used for sprites, and the bottomare used for the background graphics. All tiles are 8x8and use 4 color values (color 0 is transparent).

9 Thesecolor values index into 4 sprite palettes and 4 back-ground palettes, with some this for timing,2in many ways the CPU is sub-2 Fun fact: NTSC ( Never Twice the Same Color ), the videoservient to the PPU, kind of like the PPU is thetruepure heart of the NES. In the context of this paper,you could say that the CPU is the Ocarina of Timeand the PPU is the legend of Zelda . It s just an anal-ogy. The PPU is very complicated and has tetrahedrafor hands, like clubs. The CPU communicates with thePPU not by drawing pixels, but by giving a high-leveldescription of the screen (by writing it into PPU mem-ory).

10 The chief insight of this work is that the PPUrepresentation can be interpreted and rendered in 3 Dinstead of 2D. This allows us to use the exact originalgame logic and only change the way it s viewed. Some-times this even allows us to see aspects of the gamethat are actually present but were not visible on NEShardware. Often it makes the game more difficult bymaking things invisible (enemies behind the player orbehind walls) and inducing motion BackgroundThe PPU has two major drawing facilities: Backgroundand Sprites.