From 9a9efb1c58dbb59ac883390149b00a7b84f9e9b9 Mon Sep 17 00:00:00 2001
From: Robert Osfield <robert@openscenegraph.com>
Date: Thu, 21 Nov 2013 14:08:01 +0000
Subject: [PATCH] From Farshid Lashkari, " recently encountered an issue
 attempting to load an IVE file generated by an older version of OSG. The file
 contained dxt1 compressed image data with mipmaps. The loaded model would
 cause crashes when passing the mipmap data to glCompressedTexImage2D. It
 seems that the size of the data array within the IVE file did not match the
 computed size from Image::getTotalSizeInBytesIncludingMipmaps(). This
 essentially made the mipmap offsets invalid within the Image object.

I'm not sure if the IVE was simply generated incorrectly, or if the Image::getTotalSizeInBytesIncludingMipmaps() was modified since the file was generated. Either way, I added a simple check in the IVE loader so that it clears the mipmap offsets if the actual data size does not match the computed data size. This seems like a safe fallback since the mipmap data can be automatically generated, and it fixes the problem in my case.

Also, while looking into this issue, I noticed that the osgDB::InputStream class applies the serialized image allocation mode. However, since the serializer is allocating the image data itself, it seems like it should force the allocation mode to USE_NEW_DELETE.
"