Choose GetProcAddr function inside each generated package.

This replaces the old procaddr/* packages.

package.go

@@ -50,6 +50,9 @@ func (pkg *Package) GeneratePackage(dir string) error {
 	if err := pkg.generateFile("conversions", dir); err != nil {
 		return err
 	}
+	if err := pkg.generateFile("procaddr", dir); err != nil {
+		return err
+	}
 	if pkg.HasDebugCallbackFeature() {
 		if err := pkg.generateFile("debug", dir); err != nil {
 			return err

package.tmpl

@@ -71,8 +71,6 @@ import (
   {{if .HasRequiredFunctions}}
   "errors"
   {{end}}
-  "{{.Prefix}}/procaddr"
-  "{{.Prefix}}/procaddr/auto"
   "unsafe"
 )
 
@@ -110,10 +108,13 @@ func {{.GoName}}({{template "paramsGoDecl" .Parameters}}){{if not .Return.IsVoid
 {{end}}
 
 func Init() error {
-  return InitWithProcAddrFunc(auto.GetProcAddress)
+  return InitWithProcAddrFunc(getProcAddress)
 }
 
-func InitWithProcAddrFunc(getProcAddr procaddr.GetProcAddressFunc) error {
+// InitWithProcAddrFunc intializes the package with the given getProcAddr
+// function. It is for advanced clients who wish to provide their own OpenGL
+// function pointers. For most cases Init will be used instead.
+func InitWithProcAddrFunc(getProcAddr func(name string) unsafe.Pointer) error {
   {{range .Functions}}
   gp{{.GoName}} = (C.GP{{toUpper .GoName}})(getProcAddr("{{.Name}}"))
   {{if .Required}}

procaddr.tmpl

@@ -0,0 +1,78 @@
+// This file implements GlowGetProcAddress for each platform. The correct
+// version is chosen automatically based on build tags:
+//
+// windows: WGL
+// darwin: CGL
+// linux: GLX
+//
+// Use of EGL instead of the platform's default (listed above) is made possible
+// via the "egl" build tag.
+//
+// It is also possible to install your own function outside this package for
+// retrieving OpenGL function pointers, to do this see InitWithProcAddrFunc.
+
+package {{.Name}}
+
+/*
+#cgo windows CFLAGS: -DTAG_WINDOWS
+#cgo windows LDFLAGS: -lopengl32
+
+#cgo darwin CFLAGS: -DTAG_DARWIN
+#cgo darwin LDFLAGS: -framework OpenGL
+
+#cgo linux CFLAGS: -DTAG_LINUX
+#cgo linux LDFLAGS: -lGL
+
+#cgo egl CFLAGS: -DTAG_EGL
+#cgo egl LDFLAGS: -lEGL
+
+#ifdef TAG_WINDOWS
+	#define WIN32_LEAN_AND_MEAN 1
+	#include <windows.h>
+	#include <stdlib.h>
+	static HMODULE ogl32dll = NULL;
+	void* GlowGetProcAddress(const char* name) {
+		void* pf = wglGetProcAddress((LPCSTR)name);
+		if(pf) {
+			return pf;
+		}
+		if(ogl32dll == NULL) {
+			ogl32dll = LoadLibraryA("opengl32.dll");
+		}
+		return GetProcAddress(ogl32dll, (LPCSTR)name);
+	}
+#endif
+
+#ifdef TAG_DARWIN
+	#include <stdlib.h>
+	#include <dlfcn.h>
+	void* GlowGetProcAddress(const char* name) {
+		return dlsym(RTLD_DEFAULT, name);
+	}
+#endif
+
+#ifdef TAG_LINUX
+	#include <stdlib.h>
+	#include <GL/glx.h>
+	void* GlowGetProcAddress(const char* name) {
+		return glXGetProcAddress(name);
+	}
+#endif
+
+#ifdef TAG_EGL
+	#include <stdlib.h>
+	#include <EGL/egl.h>
+	void* GlowGetProcAddress(const char* name) {
+		return eglGetProcAddress(name);
+	}
+#endif
+*/
+import "C"
+
+import "unsafe"
+
+func getProcAddress(namea string) unsafe.Pointer {
+	cname := C.CString(namea)
+	defer C.free(unsafe.Pointer(cname))
+	return C.GlowGetProcAddress(cname)
+}

type.go

@@ -75,7 +75,7 @@ func (t Type) GoType() string {
 	case "GLfixed":
 		return t.pointers() + "int32"
 	case "GLchar", "GLcharARB":
-    // Chosen (vs. byte) for compatibility where GL uses GLubyte for strings (e.g., glGetString)
+		// Chosen (vs. byte) for compatibility where GL uses GLubyte for strings (e.g., glGetString)
 		return t.pointers() + "uint8"
 	case "GLboolean":
 		return t.pointers() + "bool"