Add support for using the latest available OpenGL version

[libs/gui.git] / source / graphics / wgl / glcontext.cpp

diff --git a/source/graphics/wgl/glcontext.cpp b/source/graphics/wgl/glcontext.cpp
index 68088970ac13cab32cd856a2a23980d838ad3bf7..b0f685b582a835e38b9639073c6da8564b855e32 100644 (file)
--- a/source/graphics/wgl/glcontext.cpp
+++ b/source/graphics/wgl/glcontext.cpp
@@ -2,6 +2,8 @@
 #include <windows.h>
 #include <GL/gl.h>
 #include <GL/wglext.h>
+#include <msp/strings/lexicalcast.h>
+#include <msp/strings/utils.h>
 #include "glcontext.h"
 #include "window_private.h"
 
@@ -53,7 +55,7 @@ void GLContext::platform_init(const GLOptions &opts)
        SetPixelFormat(dc, pf_index, &pfd);
 
        priv = new Private;
-       if(opts.forward_compatible || opts.gl_version_major)
+       if(opts.forward_compatible || opts.gl_version_major!=DEFAULT_VERSION)
        {
                ContextHandle fake_context = wglCreateContext(dc);
                wglMakeCurrent(dc, fake_context);
@@ -62,6 +64,21 @@ void GLContext::platform_init(const GLOptions &opts)
                if(!wglCreateContextAttribs)
                        throw unsupported_gl_mode(opts);
 
+               unsigned gl_version_major = opts.gl_version_major;
+               unsigned gl_version_minor = opts.gl_version_minor;
+               if(opts.gl_version_major==GLOptions::LATEST_VERSION)
+               {
+                       const char *gl_ver_ptr = reinterpret_cast<const char *>(glGetString(GL_VERSION));
+                       if(!gl_ver_ptr)
+                               throw unsupported_gl_mode(opts);
+
+                       string gl_ver = gl_ver_ptr;
+                       vector<string> parts = split(gl_ver.substr(0, gl_ver.find(' ')), '.');
+
+                       gl_version_major = lexical_cast<unsigned>(parts[0]);
+                       gl_version_minor = lexical_cast<unsigned>(parts[1]);
+               }
+
                vector<int> ctx_attribs;
 
                if(opts.forward_compatible)
@@ -79,9 +96,9 @@ void GLContext::platform_init(const GLOptions &opts)
                if(opts.gl_version_major)
                {
                        ctx_attribs.push_back(WGL_CONTEXT_MAJOR_VERSION_ARB);
-                       ctx_attribs.push_back(opts.gl_version_major);
+                       ctx_attribs.push_back(gl_version_major);
                        ctx_attribs.push_back(WGL_CONTEXT_MINOR_VERSION_ARB);
-                       ctx_attribs.push_back(opts.gl_version_minor);
+                       ctx_attribs.push_back(gl_version_minor);
                }
 
                ctx_attribs.push_back(0);