texture-rg: 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/texture-rg - from package: piglit

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

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