User:GreenThePear/Sandbox
rgbl is an esoteric graphical programming language, it is written by drawing a bitmap image which is self-modifying. The head of the program travels along the pixels and each the level of each pixel's color corresponds to a different logic component:
- Red: instruction signature
- Green: value (v)
- Blue: step direction
Outside the bitmap data itself, rgbl stores a single value in memory (m).
Instructions
An instruction can draw a value into a pixel (modify G) or save a value to memory (it "mems"). Every instruction except cross is followed by moving the head in the direction defined by B.
| R | Name | Draws | Mems | |
|---|---|---|---|---|
| 255 | cross | m
|
m
| |
| 0 - 63: General | ||||
| 0 | draw | m
|
m
| |
| 1 | mem | v
|
v
| |
| 2 | swap | m
|
v
| |
| 64 - 127: IO | ||||
| 64* | stdout | v
|
m
| |
| 65** | stdin | stdin | stdin | |
| 128 - 191: Arithmetic | ||||
| 128 | add | v
|
m+v
| |
| 129 | sub | v
|
m-v
| |
| 130 | mult | v
|
m*v
| |
| 131 | div | v
|
m//v
| |
| 132 | mod | v
|
m%v
| |
| 192 - 254: Boolean | ||||
| 192 | eq | v
|
m==v
| |
| 193 | lt | v
|
m<v
| |
| 194 | le | v
|
m<=v
| |
| 195 | gt | v
|
m>v
| |
| 196 | ge | v
|
m>=v
| |
* stdout prints the corresponding ASCII character to v
** stdin reads a character from stdin and draws and mems it
In the table v is always the value before any drawing, so drawing v just means leaving the pixel unchanged. R outside of the defined instructions will just be looped through for the rest of the category, so for example one can call add with 128 but also 133, 138, 143, 148 and so on until 188.
Cross
Cross will only move the tape to the direction defined by B if m equals 0. If it equals 1, then the direction flips 180° degrees and continues in the following pattern for any m%8, here assuming that B directs up:
| 4 | 0 | 6 |
| 2 | 3 | |
| 7 | 1 | 5 |