uint32_t zofits::ShrinkCatalog ( )

inline

Shrinks a catalog that is too long to fit into the reserved space at the beginning of the file.

Definition at line 415 of file zofits.h.

References i.

        {
            //add empty row to get either the target number of rows, or a multiple of the allowed size
            for (uint32_t i=0;i<fCatalogSize%fNumTiles;i++)
                AddOneCatalogRow();

            //did we write more rows than what the catalog could host ?
            if (fCatalogSize <= fNumTiles) // nothing to do
                return 1;

            //always exact as extra rows were added just above
            const uint32_t shrink_factor = fCatalogSize / fNumTiles; 

            //shrink the catalog !
            uint32_t entry_id = 1;
            auto it = fCatalog.begin();
            it++;
            for (; it != fCatalog.end(); it++)
            {
                if (entry_id >= fNumTiles)
                    break;

                const uint32_t target_id = entry_id*shrink_factor;

                auto jt = it;
                for (uint32_t i=0; i<target_id-entry_id; i++)
                    jt++;

                *it = *jt;

                entry_id++;
            }

            const uint32_t num_tiles_to_remove = fCatalogSize-fNumTiles;

            //remove the too many entries
            for (uint32_t i=0;i<num_tiles_to_remove;i++)
            {
                fCatalog.pop_back();
                fCatalogSize--;
            }

            //update header keywords
            fNumRowsPerTile *= shrink_factor;

            SetInt("ZTILELEN", fNumRowsPerTile);
            SetInt("ZSHRINK",  shrink_factor);

            return shrink_factor;
        }