Engine directory for ticket #1

Engine/source/gfx/gl/ggl/mac/aglBind.cpp

@@ -0,0 +1,195 @@
+//-----------------------------------------------------------------------------
+// Copyright (c) 2012 GarageGames, LLC
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to
+// deal in the Software without restriction, including without limitation the
+// rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+// sell copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+// IN THE SOFTWARE.
+//-----------------------------------------------------------------------------
+
+#include <err.h>
+#include "agl.h"
+
+#include "platform/platform.h"
+
+//-----------------------------------------------------------------------------
+// Instantiation of function pointers.
+
+#define GL_GROUP_BEGIN(name)
+#define GL_FUNCTION(name, type, args) type (XGL_DLL *name) args;
+#define GL_GROUP_END()
+#include "../generated/glcfn.h"
+#undef GL_GROUP_BEGIN
+#undef GL_FUNCTION
+#undef GL_GROUP_END
+
+
+#define EXECUTE_ONLY_ONCE() \
+         static bool _doneOnce = false; \
+         if(_doneOnce) return; \
+         _doneOnce = true;
+
+namespace GL
+{
+
+//-----------------------------------------------------------------------------
+// The OpenGL Bundle is shared by all the devices.
+static CFBundleRef   _openglFrameworkRef;
+
+// Unlike WGL, AGL does not require a set of function pointers per
+// context pixel format. All functions in the DLL are bound in a single
+// table and shared by all contexts.
+static AGLExtensionPtrs _LibraryFunctions;
+static AGLExtensionFlags _ExtensionFlags;
+
+bool hasExtension(const char *name,const char* extensions);
+bool hasVersion(const char *name,const char* prefix,int major,int minor);
+
+
+//-----------------------------------------------------------------------------
+void* MacGetProcAddress(CFBundleRef bundle,char* name)
+{
+   CFStringRef cfName = CFStringCreateWithCString(kCFAllocatorDefault, name, CFStringGetSystemEncoding());
+   void* ret = CFBundleGetFunctionPointerForName(bundle, cfName);
+   CFRelease(cfName);
+   return ret;
+}
+
+
+//-----------------------------------------------------------------------------
+bool bindFunction(CFBundleRef bundle,void *&fnAddress, const char *name)
+{
+   CFStringRef cfName = CFStringCreateWithCString(0,name,CFStringGetSystemEncoding());
+   fnAddress = CFBundleGetFunctionPointerForName(bundle, cfName);
+   CFRelease(cfName);
+   return fnAddress != 0;
+}
+
+
+//-----------------------------------------------------------------------------
+bool gglBindCoreFunctions(CFBundleRef bundle,AGLExtensionPtrs* glp)
+{
+   bool bound = true;
+
+   // Bind static functions which are quarenteed to be part of the
+   // OpenGL library. In this case, OpenGL 1.0 and GLX 1.0 functions
+   #define GL_GROUP_BEGIN(name)
+   #define GL_GROUP_END()
+   #define GL_FUNCTION(fn_name, fn_return, fn_args) \
+         bound &= bindFunction(bundle,*(void**)&fn_name, #fn_name);
+   #include "../generated/glcfn.h"
+   #undef GL_FUNCTION
+   #undef GL_GROUP_BEGIN
+   #undef GL_GROUP_END
+
+   // Try and bind all known extension functions. We'll check later to
+   // see which ones are actually valid for a context.
+   #define GL_GROUP_BEGIN(name)
+   #define GL_FUNCTION(fn_name, fn_return, fn_args) \
+            bindFunction(bundle,*(void**)&glp->_##fn_name, #fn_name);
+   #define GL_GROUP_END()
+   #include "../generated/glefn.h"
+   #undef GL_FUNCTION
+   #undef GL_GROUP_BEGIN
+   #undef GL_GROUP_END
+
+   return bound;
+}
+
+
+//-----------------------------------------------------------------------------
+bool gglBindExtensions(GLExtensionFlags* gl)
+{
+   dMemset(gl,0,sizeof(GLExtensionFlags));
+
+   // Get GL version and extensions
+   const char* glExtensions = (const char*)glGetString(GL_EXTENSIONS);
+   const char* glVersion = (const char*) glGetString(GL_VERSION);
+   if (!glExtensions || !glVersion)
+      return false;
+
+   // Parse the GL version string "major.minor"
+   const char *itr = glVersion;
+   int glMajor = atoi(itr);
+   while (isdigit(*itr))
+      *itr++;
+   int glMinor = atoi(++itr);
+
+   // Check which extensions are available on the active context.
+   // GL and GLX versions ubove 1.0 are also tested here.
+   #define GL_GROUP_BEGIN(name) \
+         gl->has_##name = hasVersion(#name,"GL_VERSION",glMajor,glMinor) || \
+            hasExtension(#name,glExtensions);
+   #define GL_FUNCTION(fn_name, fn_return, fn_args)
+   #define GL_GROUP_END()
+   #include "../generated/glefn.h"
+   #undef GL_FUNCTION
+   #undef GL_GROUP_BEGIN
+   #undef GL_GROUP_END
+
+   gl->bound = true;
+   return true;
+}
+
+#define _hasGLXExtension(display,name) (display->glx.has_##name)
+
+//-----------------------------------------------------------------------------
+void gglPerformBinds()
+{
+   // Some of the following code is copied from the Apple Opengl Documentation.
+  
+   // Load and bind OpenGL bundle functions
+   if (!_openglFrameworkRef) {
+   
+      // Load OpenGL.framework
+      _openglFrameworkRef = CFBundleGetBundleWithIdentifier(CFSTR("com.apple.opengl"));
+      if (!_openglFrameworkRef) {
+         warn("Could not create OpenGL Framework bundle");
+         return;
+      }
+      if (!CFBundleLoadExecutable(_openglFrameworkRef)) {
+         warn("Could not load MachO executable");
+         return;
+      }
+
+      // Bind our functions.
+      if (!gglBindCoreFunctions(_openglFrameworkRef, &_LibraryFunctions)) {
+         warn("GLDevice: Failed to bind all core functions");
+         return;
+      }
+
+      // Save the pointer to the set of opengl functions
+      _GGLptr = &_LibraryFunctions;
+   }
+}
+
+//-----------------------------------------------------------------------------
+void gglPerformExtensionBinds(void *context)
+{
+   // we don't care about the passed context when binding the opengl functions,
+   // we only care about the current opengl context.
+	if( !_openglFrameworkRef || !_GGLptr )
+	{
+		gglPerformBinds();
+	}
+   gglBindExtensions(  &_ExtensionFlags );
+   _GGLflag = &_ExtensionFlags;
+}
+
+
+
+} // Namespace
+