RFC 336

Level 0 Graphic Input Protocol 🎀

okay bestie, this is the RFC that sets up the most basic level of graphic input 💖 It's from 5 May 1972 and it was written by Ira Cotton at Mitre ✨ It's filed as NIC 9929 and NWG/RFC #336. The document doesn't say what category or status it has, and it doesn't say whether it obsoletes or updates anything 🙈

okay so the network Graphics working group met on April 16-18 and started thinking about defining levels of protocol for graphic Input Protocol 🧚 this doc is about Level 0 🌸

the vibe is the same as in RFC #178, "Network Graphic Attention Handling." 💜 the basic idea is that all input gets described by its type, its origin, and its length, and then the actual data comes after that 🫶

at Level 0 there are only two types of input: text and simple position 🦋

Text Input

text input gets sent in this format:

TEXTIN : DEVICE : COUNT: Text String

• TEXTIN is the protocol code that tells you this string is input. For now, this code is 1 💅
• DEVICE is a code for the device the input came from. These are the codes right now:

0 - unspecified device
1 - primary keyboard
2 - tablet
3 - mouse
4 - joystick
5 - lightpen
6 - cursor
7 - keyset
8 - mouse & keyset

• COUNT is an integer that tells you how many characters (bytes) come after it 🍓
• Text String is a string of "Count" bytes of characters in network ASCII ✨

Position Input

simple position data gets sent in this format:

POSIT : DEVICE : COUNT : x : y

• POSIT is the protocol code that says this string has position data. For now, this code is 2 🌈
• DEVICE is the input device that made this data. The codes are the same as the ones above 💖
• COUNT is an integer for how many bytes of data come after it. That includes both the x and y coordinates, so the number of bytes for x is COUNT divided by 2 🧮 at level 0, COUNT should always be 4, since every coordinate is 2 bytes at this level 👑
• x and y coordinate data are written as signed fractions, the same way position data is written in the Level 0 graphic output protocol 🔥

it's really important that input data from a level 0 graphics user that doesn't match one of the formats above should be sent on a different link than the graphics input link ⚠️ apps might want to do this to skip the overhead of the protocol, which is honestly iconic 💅

[ This RFC was put into machine readable form for entry ]
[ into the online RFC archives by BBN Corp. under the   ]
[ direction of Alex McKenzie.                   12/96   ]