This fixes a number of things that are warnings in the Mac compiler....

core/cross/pack.cc

 /*
  * Copyright 2009, Google Inc.
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
@@ skipping 150 matching lines @@
 
 // Creates a Texture object from a bitmap in the current render context format.
 Texture* Pack::CreateTextureFromBitmap(Bitmap *bitmap, const String& uri) {
   DCHECK(bitmap);
 
   if (!renderer_) {
     O3D_ERROR(service_locator()) << "No Render Device Available";
     return NULL;
   }
 
-  if (bitmap->width() > Texture::MAX_DIMENSION ||
-      bitmap->height() > Texture::MAX_DIMENSION) {
+  if (bitmap->width() > static_cast<unsigned int>(Texture::MAX_DIMENSION) ||
+      bitmap->height() > static_cast<unsigned int>(Texture::MAX_DIMENSION)) {
     O3D_ERROR(service_locator())
         << "Texture (uri='" << uri
         << "', size="  << bitmap->width() << "x" << bitmap->height()
         << ", mips=" << bitmap->num_mipmaps()<< ") is larger than the "
         << "maximum texture size which is (" << Texture::MAX_DIMENSION
         << "x" << Texture::MAX_DIMENSION << ")";
     return NULL;
   }
 
   Texture::Ref texture = renderer_->CreateTextureFromBitmap(bitmap);
@@ skipping 91 matching lines @@
 
   if (width > Texture::MAX_DIMENSION ||
       height > Texture::MAX_DIMENSION) {
     O3D_ERROR(service_locator())
         << "Maximum texture size is (" << Texture::MAX_DIMENSION << "x"
         << Texture::MAX_DIMENSION << ")";
     return NULL;
   }
 
   if (enable_render_surfaces) {
-    if (Bitmap::GetPOTSize(width) != width ||
-        Bitmap::GetPOTSize(height) != height) {
+    if (Bitmap::GetPOTSize(width) != static_cast<unsigned int>(width) ||
+        Bitmap::GetPOTSize(height) != static_cast<unsigned int>(height)) {
       O3D_ERROR(service_locator()) <<
           "Textures with RenderSurfaces enabled must have power-of-two "
           "dimensions.";
       return NULL;
     }
   }
 
   Texture2D::Ref texture = renderer_->CreateTexture2D(
       width,
       height,
@@ skipping 19 matching lines @@
   }
 
   if (edge_length > Texture::MAX_DIMENSION) {
     O3D_ERROR(service_locator())
         << "Maximum edge_length is " << Texture::MAX_DIMENSION;
     return NULL;
   }
 
 
   if (enable_render_surfaces) {
-    if (Bitmap::GetPOTSize(edge_length) != edge_length) {
+    if (Bitmap::GetPOTSize(edge_length) !=
+        static_cast<unsigned int>(edge_length)) {
       O3D_ERROR(service_locator()) <<
           "Textures with RenderSurfaces enabled must have power-of-two "
           "dimensions.";
       return NULL;
     }
   }
 
   TextureCUBE::Ref texture = renderer_->CreateTextureCUBE(
       edge_length,
       format,
@@ skipping 15 matching lines @@
   }
 
   if (width > Texture::MAX_DIMENSION ||
       height > Texture::MAX_DIMENSION) {
     O3D_ERROR(service_locator())
         << "Maximum texture size is (" << Texture::MAX_DIMENSION << "x"
         << Texture::MAX_DIMENSION << ")";
     return NULL;
   }
 
-  if (Bitmap::GetPOTSize(width) != width ||
-      Bitmap::GetPOTSize(height) != height) {
+  if (Bitmap::GetPOTSize(width) != static_cast<unsigned int>(width) ||
+      Bitmap::GetPOTSize(height) != static_cast<unsigned int>(height)) {
     O3D_ERROR(service_locator()) <<
         "Depth-stencil RenderSurfaces must have power-of-two dimensions.";
     return NULL;
   }
 
   RenderDepthStencilSurface::Ref surface =
       renderer_->CreateDepthStencilSurface(width, height);
 
   if (!surface.IsNull()) {
     RegisterObject(surface);
@@ skipping 53 matching lines @@
 
 bool Pack::UnregisterObject(ObjectBase *object) {
   ObjectSet::iterator find(owned_objects_.find(ObjectBase::Ref(object)));
   if (find == owned_objects_.end())
     return false;
 
   owned_objects_.erase(find);
   return true;
 }
 }  // namespace o3d