Shell Video Batch Tutorial #3 :mathMacros, Drawing shapes!

Code
@echo off & setlocal enableDelayedExpansion



call :canvas 50 40

call :mathMacros



set "r1=13"

set "r2=18"



:main



    set /a "angle+=2"

    

    set /a "x=r1 * !sin(x):x=angle!"

    set /a "y=r2 * !cos(x):x=angle!"

    

    set /a "%translate%"



    call :plot x y .



    call :showCanvas

    REM call :updateCanvas



goto :main















:mathMacros

    set /a "PI=(35500000/113+5)/10, PI_div_2=(35500000/113/2+5)/10, PIx2=2*PI, PI32=PI+PI_div_2"

    set "_SIN=a-a*a/1920*a/312500+a*a/1920*a/15625*a/15625*a/2560000-a*a/1875*a/15360*a/15625*a/15625*a/16000*a/44800000"

    set "SIN(x)=(a=(x * 31416 / 180)%%62832, c=(a>>31|1)*a, a-=(((c-47125)>>31)+1)*((a>>31|1)*62832)  +  (-((c-47125)>>31))*( (((c-15709)>>31)+1)*(-(a>>31|1)*31416+2*a)  ), %_SIN%) / 10000"

    set "COS(x)=(a=(15708 - x * 31416 / 180)%%62832, c=(a>>31|1)*a, a-=(((c-47125)>>31)+1)*((a>>31|1)*62832)  +  (-((c-47125)>>31))*( (((c-15709)>>31)+1)*(-(a>>31|1)*31416+2*a)  ), %_SIN%) / 10000"

    set "_SIN="

    set "Sqrt(N)=( M=(N), x=M/(11*1024)+40, x=(M/x+x)>>1, x=(M/x+x)>>1, x=(M/x+x)>>1, x=(M/x+x)>>1, x=(M/x+x)>>1, x+=((M-x*x)>>31)/(1+((N)>>31)) )"

    set "Abs(x)=(((x)>>31|1)*(x))"

   

    set "swap(x,y)=t=x, x=y, y=t"

    set "translate=x+=width / 2, y+=height / 2"

goto :eof





:canvas

        set /a "width=%~1 - 1", "height=%~2 - 1", "conWidth=width + 5", "conHeight=height + 6", "_=0"

        for /l %%a in (-2,1,%width%) do set "outerBuffer=!outerBuffer!#"

        for /l %%a in (0,1,%width%)  do set "widthBuffer=!widthBuffer! "

        call :updateCanvas

        call :cursorpos

        if exist "%temp%\cursorpos.exe" ( set "cls="%temp%\cursorpos.exe" 0 1" ) else ( set "cls=cls" )

        mode con: cols=%conWidth% lines=%conHeight%

    goto :eof

    

    :updateCanvas

        for /l %%a in (0,1,%height%) do set "_[%%a]=%widthBuffer%"

    goto :eof

    

    :showCanvas

        %cls%

        echo= %outerBuffer%

        for /l %%a in (0,1,%height%) do echo= #!_[%%a]!#

        echo= %outerBuffer%

        if "%~1" equ "/u" for /l %%a in (0,1,%height%) do set "_[%%a]=%widthBuffer%"

    goto :eof

goto :eof



:plot x y

    setlocal

        set /a "_y=%~2", "_x=%~1", "_x2=%~1 + 1"

        (endlocal

            set "_[%_y%]=!_[%_y%]:~0,%_x%!%~3!_[%_y%]:~%_x2%!"

        )

goto :eof