1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/*
 * This file is part of the LibreOffice project.
 *
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/.
 *
 * This file incorporates work covered by the following license notice:
 *
 *   Licensed to the Apache Software Foundation (ASF) under one or more
 *   contributor license agreements. See the NOTICE file distributed
 *   with this work for additional information regarding copyright
 *   ownership. The ASF licenses this file to you under the Apache
 *   License, Version 2.0 (the "License"); you may not use this file
 *   except in compliance with the License. You may obtain a copy of
 *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
 */

#include <sal/config.h>

#include "pagemanager.hxx"

namespace canvas
{
    FragmentSharedPtr PageManager::allocateSpace( const ::basegfx::B2ISize& rSize )
    {
        // we are asked to find a location for the requested size.
        // first we try to satisfy the request from the
        // remaining space in the existing pages.
        for( const auto& pPage : maPages )
        {
            FragmentSharedPtr pFragment( pPage->allocateSpace(rSize) );
            if(pFragment)
            {
                // the page created a new fragment, since we maybe want
                // to consolidate sparse pages we keep a reference to
                // the fragment.
                maFragments.push_back(pFragment);
                return pFragment;
            }
        }

        // otherwise try to create a new page and allocate space there...
        PageSharedPtr pPage(new Page(mpRenderModule));
        if(pPage->isValid())
        {
            maPages.push_back(pPage);
            FragmentSharedPtr pFragment(pPage->allocateSpace(rSize));
            if (pFragment)
                maFragments.push_back(pFragment);
            return pFragment;
        }

        // the rendermodule failed to create a new page [maybe out
        // of videomemory], and all other pages could not take
        // the new request. we decide to create a 'naked' fragment
        // which will receive its location later.
        FragmentSharedPtr pFragment(new PageFragment(rSize));
        maFragments.push_back(pFragment);
        return pFragment;
    }

    void PageManager::free( const FragmentSharedPtr& pFragment )
    {
        // erase the reference to the given fragment from our
        // internal container.
        FragmentContainer_t::iterator it(
            std::remove(
                maFragments.begin(),maFragments.end(),pFragment));
        maFragments.erase(it,maFragments.end());

        // let the fragment itself know about it...
        // we need to pass 'this' as argument since the fragment
        // needs to pass this to the page and can't create
        // shared_ptr from itself...
        pFragment->free(pFragment);
    }

    void PageManager::nakedFragment( const FragmentSharedPtr& pFragment )
    {
        if(maPages.empty())
            return;

        // okay, one last chance is left, we try all available
        // pages again. maybe some other fragment was deleted
        // and we can exploit the space.
        while( !( relocate( pFragment ) ) )
        {
            // no way, we need to free up some space...
            // TODO(F1): this is a heuristic, could
            // be designed as a policy.
            auto       aEnd( maFragments.cend() );
            auto       aCurrMax( aEnd );
            sal_uInt32 nCurrMaxArea = 0;
            for( auto aCurr = maFragments.begin(); aCurr != aEnd; ++aCurr )
            {
                if( *aCurr && !( ( *aCurr )->isNaked() ) )
                {
                    const ::basegfx::B2ISize& rSize( ( *aCurr )->getSize() );
                    sal_uInt32                nArea( rSize.getX() * rSize.getY() );

                    if( nCurrMaxArea < nArea )
                    {
                        aCurrMax = aCurr;
                        nCurrMaxArea = nArea;
                    }
                }
            }
            // this does not erase the candidate,
            // but makes it 'naked'...
            if( aCurrMax != aEnd )
                ( *aCurrMax )->free( *aCurrMax );
            else
                break;
        }
    }

    bool PageManager::relocate( const FragmentSharedPtr& pFragment )
    {
        // the fragment passed as argument is assumed to
        // be naked, that is it is not located on any page.
        // we try all available pages again, maybe some
        // other fragment was deleted and we can exploit the space.
        for( const auto& pPage : maPages )
        {
            // if the page at hand takes the fragment, we immediately
            // call select() to pull the information from the associated
            // image to the hardware surface.
            if( pPage->nakedFragment( pFragment ) )
            {<--- Consider using std::any_of algorithm instead of a raw loop.
                // dirty, since newly allocated.
                pFragment->select(true);
                return true;
            }
        }
        return false;
    }

    void PageManager::validatePages()
    {
        for( const auto& rPagePtr : maPages )
            rPagePtr->validate();
    }

    ::basegfx::B2ISize PageManager::getPageSize() const
    {
        return mpRenderModule->getPageSize();
    }
}

/* vim:set shiftwidth=4 softtabstop=4 expandtab: */