Ability to request an OpenGL version from SGCT using commandline arguments

include/openspace/engine/openspaceengine.h

@@ -53,7 +53,7 @@ namespace scripting {
 
 class OpenSpaceEngine {
 public:
-    static bool create(int argc, char** argv, std::vector<std::string>& sgctArguments);
+    static bool create(int argc, char** argv, std::vector<std::string>& sgctArguments, std::string& openGlVersion);
     static void destroy();
     static OpenSpaceEngine& ref();
 

src/engine/openspaceengine.cpp

@@ -24,7 +24,6 @@
 
 #include <openspace/engine/openspaceengine.h>
 
-// sgct
 #define SGCT_WINDOWS_INCLUDE
 #include <sgct.h>
 #include <openspace/version.h>
@@ -73,10 +72,13 @@ namespace {
 	const std::string _defaultCacheLocation = "${BASE_PATH}/cache";
     
     const std::string _sgctConfigArgumentCommand = "-config";
+
+    const std::string DefaultOpenGlVersion = "4.3";
     
     struct {
         std::string configurationName;
 		std::string sgctConfigurationName;
+        std::string openGlVersion;
     } commandlineArgumentPlaceholders;
 }
 
@@ -123,8 +125,10 @@ OpenSpaceEngine& OpenSpaceEngine::ref() {
     return *_engine;
 }
 
-bool OpenSpaceEngine::create(int argc, char** argv,
-							 std::vector<std::string>& sgctArguments)
+bool OpenSpaceEngine::create(
+    int argc, char** argv,
+    std::vector<std::string>& sgctArguments,
+    std::string& openGlVersion)
 {
 	assert(_engine == nullptr);
 
@@ -225,6 +229,9 @@ bool OpenSpaceEngine::create(int argc, char** argv,
 		sgctConfigurationPath = commandlineArgumentPlaceholders.sgctConfigurationName;
 	}
 
+    openGlVersion = commandlineArgumentPlaceholders.openGlVersion;
+    LINFO("Using OpenGL version " << openGlVersion);
+
 	// Prepend the outgoing sgctArguments with the program name
 	// as well as the configuration file that sgct is supposed to use
 	sgctArguments.insert(sgctArguments.begin(), argv[0]);
@@ -354,7 +361,14 @@ bool OpenSpaceEngine::gatherCommandlineArguments() {
 		"Provides the path to the SGCT configuration file, overriding the value set in"
 		"the OpenSpace configuration file");
 	_commandlineParser->addCommand(sgctConfigFileCommand);
-    
+
+    commandlineArgumentPlaceholders.openGlVersion = DefaultOpenGlVersion;
+    CommandlineCommand* openGlVersionCommand = new SingleCommand<std::string>(
+        &commandlineArgumentPlaceholders.openGlVersion,
+        "-ogl", "-o",
+        "Sets the OpenGL version that is to be used; valid values are '4.2' and '4.3'");
+    _commandlineParser->addCommand(openGlVersionCommand);
+
     return true;
 }
 

src/main.cpp

@@ -56,11 +56,15 @@ namespace {
 	const std::string _loggerCat = "main";
 }
 
-int main(int argc, char** argv)
-{
+int main(int argc, char** argv) {
     // create the OpenSpace engine and get arguments for the sgct engine
     std::vector<std::string> sgctArguments;
-    const bool success = openspace::OpenSpaceEngine::create(argc, argv, sgctArguments);
+    std::string openGlVersion = "";
+    const bool success = openspace::OpenSpaceEngine::create(
+        argc, argv,
+        sgctArguments,
+        openGlVersion
+    );
     if (!success)
         return EXIT_FAILURE;
 
@@ -105,7 +109,17 @@ int main(int argc, char** argv)
 #ifdef __APPLE__
 	sgct::Engine::RunMode rm = sgct::Engine::RunMode::OpenGL_4_1_Core_Profile;
 #else
-	sgct::Engine::RunMode rm = sgct::Engine::RunMode::OpenGL_4_3_Core_Profile;
+    std::map<std::string, sgct::Engine::RunMode> versionMapping = {
+        { "4.2", sgct::Engine::RunMode::OpenGL_4_2_Core_Profile },
+        { "4.3", sgct::Engine::RunMode::OpenGL_4_3_Core_Profile },
+        { "4.4", sgct::Engine::RunMode::OpenGL_4_4_Core_Profile },
+        { "4.5", sgct::Engine::RunMode::OpenGL_4_5_Core_Profile }
+    };
+    if (versionMapping.find(openGlVersion) == versionMapping.end()) {
+        LFATAL("Requested OpenGL version " << openGlVersion << " not supported");
+        return EXIT_FAILURE;
+    }
+    sgct::Engine::RunMode rm = versionMapping[openGlVersion];
 #endif
 	const bool initSuccess = _sgctEngine->init(rm);
     if (!initSuccess) {