BATCH Basic Paint (not mine)

@echo off
:klik
For /f "tokens=1,2,3" %%W in ('"Mouse.exe"') do set /a "c=%%W,x=%%X,y=%%Y"
set /a x=x+1 & set /a y=y+1
wbat fill %x%,%y% (1,1) (gray on gray)
goto klik