sampler-cube-shadow: command not found

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH
/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin

If it's empty, You may set the PATH variable with this command

export PATH="/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin"

On CentOS possible default full paths are:

/usr/lib64/piglit/bin/sampler-cube-shadow - from package: piglit

You may install the required package with command yum install {package}

Error in other languages:
sampler-cube-shadow: bevel nie gevind nie
sampler-cube-shadow: comandă negăsită
sampler-cube-shadow: comando não encontrado
sampler-cube-shadow: commande introuvable
sampler-cube-shadow: command not found
sampler-cube-shadow: käsku ei ole
sampler-cube-shadow: không tìm thấy lệnh
sampler-cube-shadow: komanda nerasta
sampler-cube-shadow: Kommando nicht gefunden.
sampler-cube-shadow: kommandot finns inte
sampler-cube-shadow: komut yok
sampler-cube-shadow: nie znaleziono polecenia
sampler-cube-shadow: níor aimsíodh an t-ordú
sampler-cube-shadow: no se encontró la orden
sampler-cube-shadow: no s'ha trobat l'ordre
sampler-cube-shadow: opdracht niet gevonden
sampler-cube-shadow: parancs nem található
sampler-cube-shadow: perintah tidak ditemukan
sampler-cube-shadow: príkaz nenájdený
sampler-cube-shadow: příkaz nenalezen
sampler-cube-shadow: команда не найдена
sampler-cube-shadow: командата не е открита
sampler-cube-shadow: 命令找不到
sampler-cube-shadow: コマンドが見つかりません