X-Git-Url: http://git.tdb.fi/?a=blobdiff_plain;f=source%2Fcore%2Fbackend.cpp;fp=source%2Fcore%2Fbackend.cpp;h=c3e159f427ef339c4a9e46f4418cfb28e17f4ed1;hb=e6077f9f25b794c174e1017c2c0763e77a6fddda;hp=0000000000000000000000000000000000000000;hpb=8e553af57b712051f47293c971671f4f6a939be2;p=libs%2Fgl.git

diff --git a/source/core/backend.cpp b/source/core/backend.cpp
new file mode 100644
index 00000000..c3e159f4
--- /dev/null
+++ b/source/core/backend.cpp
@@ -0,0 +1,76 @@
+#include <stdexcept>
+#include <cstdlib>
+#include <msp/strings/lexicalcast.h>
+#include <msp/strings/utils.h>
+#include "backend.h"
+#include "gl.h"
+
+using namespace std;
+
+namespace Msp {
+namespace GL {
+
+Version::Version()
+{
+	major = 0;
+	minor = 0;
+}
+
+Version::Version(unsigned short a, unsigned short i)
+{
+	major = a;
+	minor = i;
+}
+
+Version::Version(const string &s)
+{
+	vector<string> parts = split(s, '.');
+	major = lexical_cast<unsigned>(parts[0]);
+	minor = lexical_cast<unsigned>(parts[1]);
+}
+
+bool Version::operator>=(const Version &other) const
+{
+	return major>other.major || (major==other.major && minor>=other.minor);
+}
+
+
+GraphicsApi get_backend_api()
+{
+#ifdef GL_ES_VERSION_2_0
+	return OPENGL_ES;
+#else
+	return OPENGL;
+#endif
+}
+
+inline Version get_gl_version()
+{
+	const char *gl_ver_ptr = reinterpret_cast<const char *>(glGetString(GL_VERSION));
+	if(!gl_ver_ptr)
+		throw runtime_error("OpenGL version not available");
+
+	string gl_ver = gl_ver_ptr;
+	if(!gl_ver.compare(0, 10, "OpenGL ES "))
+		gl_ver.erase(0, 10);
+
+	Version ver(gl_ver.substr(0, gl_ver.find(' ')));
+
+	if(const char *force_ver_ptr = getenv("MSPGL_FORCE_VERSION"))
+	{
+		Version force_ver(force_ver_ptr);
+		if(force_ver<ver)
+			ver = force_ver;
+	}
+
+	return ver;
+}
+
+const Version &get_backend_version()
+{
+	static Version version = get_gl_version();
+	return version;
+}
+
+} // namespace GL
+} // namespace Msp