diff -uNr gl4es/CMakeLists.txt gl4es.mod/CMakeLists.txt
--- gl4es/CMakeLists.txt        2021-10-13 23:49:59.659443188 +0800
+++ gl4es.mod/CMakeLists.txt    2021-10-13 23:48:57.547443233 +0800
@@ -13,6 +13,7 @@
 option(BCMHOST "Set to ON if targeting an RPi(2) device" ${BCMHOST})
 option(ODROID "Set to ON if targeting an ODroid device" ${ODROID})
 option(ANDROID "Set to ON if targeting an Android device" ${ANDROID})
+option(TERMUX "Set to ON if targeting Termux environment" ${TERMUX})
 option(CHIP "Set to ON if targeting an C.H.I.P. device" ${CHIP})
 option(AMIGAOS4 "Set to ON if targeting an AmigaOS4/Warp3D platform (activate NOEGL and NOX11)" ${AMIGAOS4})
 option(NOX11 "Set to ON to not use X11 (creation of context has to be done outside gl4es)" ${NOX11})
@@ -99,6 +100,10 @@
     find_library(log-lib log)
 endif()

+if(TERMUX)
+    add_definitions(-DNO_GBM -DDEFAULT_ES=2)
+endif()
+
 #PocketCHIP
 if(CHIP)
     add_definitions(-DCHIP)