From aeff6035397486e0bffbbd654fec195ebac2995a Mon Sep 17 00:00:00 2001
From: Julien Hamaide <julien.hamaide@gmail.com>
Date: Thu, 24 Jan 2019 10:42:14 +0100
Subject: [PATCH] Option to specify minimum opengl version at compile time

---
 CMakeLists.txt   | 1 +
 cmake/bgfx.cmake | 4 ++++
 2 files changed, 5 insertions(+)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 968bcf0..d7a1511 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -29,6 +29,7 @@ option( BGFX_AMALGAMATED      "Amalgamated bgfx build for faster compilation" OF
 option( BX_AMALGAMATED        "Amalgamated bx build for faster compilation"   OFF )
 option( BGFX_CONFIG_DEBUG     "Enables debug configuration on all builds"     OFF )
 option( BGFX_USE_DEBUG_SUFFIX "Add 'd' suffix to debug output targets"        ON  )
+set( BGFX_OPENGL_VERSION  "" CACHE STRING "Specify minimum opengl version" )
 
 if( NOT BX_DIR )
 	set( BX_DIR "${CMAKE_CURRENT_SOURCE_DIR}/bx" CACHE STRING "Location of bx." )
diff --git a/cmake/bgfx.cmake b/cmake/bgfx.cmake
index 05c957f..a7cc4b7 100755
--- a/cmake/bgfx.cmake
+++ b/cmake/bgfx.cmake
@@ -43,6 +43,10 @@ if(BGFX_CONFIG_DEBUG)
 	target_compile_definitions( bgfx PRIVATE BGFX_CONFIG_DEBUG=1)
 endif()
 
+if( NOT ${BGFX_OPENGL_VERSION} STREQUAL "" )
+	target_compile_definitions( bgfx PRIVATE BGFX_CONFIG_RENDERER_OPENGL=${BGFX_OPENGL_VERSION})
+endif()
+
 # Special Visual Studio Flags
 if( MSVC )
 	target_compile_definitions( bgfx PRIVATE "_CRT_SECURE_NO_WARNINGS" )