Pixilang/Programming techniques

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Programming techniques[edit | edit source]

Getting started[edit | edit source]

Create file (f.e. MY_PROGRAM.TXT) with following text inside:

a = 2 * 2
print("HELLO PIXEL! $a",-20,10,#FFFFFF)
a = a + 1
goto marker1

And now you must execute this file with the pixilang enterpreter. After starting you will get simple animation with a text string "HELLO PIXEL" and incrementing number.

Math operations[edit | edit source]

In Pixilang all numbers are signed 32-bit integers.

It's possible to use operations without the "=" symbol. Examples:

a+1 //increment variable a

a+1*2 //add (1*2) to a

Conditional operations[edit | edit source]

Conditional operations have the following format: if SOME CONDITION { PIECE OF PROGRAM, THAT WILL BE EXECUTED IF CONDITION IS TRUE }


//If a > 4, then save 2 to variable b
if a > 4  { b = 2 } 
//If a equal to 4, then save 1 to variable b 
if a = 1  { b = 1 } 
//If b not equal to 1, then put "HELLO" string to the screen
if b != 1  { print("HELLO",1,1) } 
//If b not equal to 1, then put "HELLO" string to the screen, else draw a dot
if b != 1  { print("HELLO",1,1) } else { dot(10,10) }

Including external files[edit | edit source]

You can include external TXT files (user libraries for example). Example:

INCLUDE "external filename"

External files will be included during compilation.

Program optimization[edit | edit source]

Pixilang has great methods for optimization. Lets see an example.

This is the program:

pixi( t, 44, 44 )
pixi( a, 44, 44 )
pixi( b, 44, 44 )

As you can see, there is a recurring command name (pixi) and recurring parameters (44,44). In this case you can use following optimization:

pixi( t, 44, 44 )
.( a )
.( b )

WTF? :) It's simple. If the command name is ".", then the last executed command will be executed. If some parameters are missing, then they will be taken from the last executed command too.