vcl/opengl/FixedTextureAtlas.cxx

   1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
   2 /*
   3  * This file is part of the LibreOffice project.
   4  *
   5  * This Source Code Form is subject to the terms of the Mozilla Public
   6  * License, v. 2.0. If a copy of the MPL was not distributed with this
   7  * file, You can obtain one at http://mozilla.org/MPL/2.0/.
   8  *
   9  */
  10
  11 #include <memory>
  12 #include <sal/config.h>
  13 #include <vcl/opengl/OpenGLContext.hxx>
  14 #include <vcl/opengl/OpenGLHelper.hxx>
  15
  16 #include <opengl/framebuffer.hxx>
  17 #include <opengl/texture.hxx>
  18
  19 #include <opengl/FixedTextureAtlas.hxx>
  20
  21 #include <o3tl/make_unique.hxx>
  22
  23 struct FixedTexture
  24 {
  25     std::shared_ptr<ImplOpenGLTexture> mpTexture;
  26     int mnFreeSlots;
  27     std::vector<bool> maAllocatedSlots;
  28
  29     FixedTexture(int nTextureWidth, int nTextureHeight, int nNumberOfSlots)
  30         : mpTexture(new ImplOpenGLTexture(nTextureWidth, nTextureHeight, true))
  31         , mnFreeSlots(nNumberOfSlots)
  32         , maAllocatedSlots(nNumberOfSlots, false)
  33     {
  34         auto aDeallocateFunction = [this] (int nSlotNumber)
  35         {
  36             deallocateSlot(nSlotNumber);
  37         };
  38
  39         mpTexture->SetSlotDeallocateCallback(aDeallocateFunction);
  40         mpTexture->InitializeSlotMechanism(nNumberOfSlots);
  41     }
  42
  43     ~FixedTexture()
  44     {
  45         mpTexture->ResetSlotDeallocateCallback();
  46     }
  47
  48     void allocateSlot(int nSlot)
  49     {
  50         maAllocatedSlots[nSlot] = true;
  51         mnFreeSlots--;
  52     }
  53
  54     void deallocateSlot(int nSlot)
  55     {
  56         maAllocatedSlots[nSlot] = false;
  57         mnFreeSlots++;
  58     }
  59
  60     int findAndAllocateFreeSlot()
  61     {
  62         for (size_t i = 0; i < maAllocatedSlots.size(); ++i)
  63         {
  64             if (!maAllocatedSlots[i])
  65             {
  66                 allocateSlot(i);
  67                 return i;
  68             }
  69         }
  70         return -1;
  71     }
  72
  73 private:
  74     FixedTexture(const FixedTexture&) = delete;
  75     FixedTexture& operator=(const FixedTexture&) = delete;
  76 };
  77
  78 FixedTextureAtlasManager::FixedTextureAtlasManager(int nWidthFactor, int nHeightFactor, int nSubTextureSize)
  79     : mWidthFactor(nWidthFactor)
  80     , mHeightFactor(nHeightFactor)
  81     , mSubTextureSize(nSubTextureSize)
  82 {
  83 }
  84
  85 FixedTextureAtlasManager::~FixedTextureAtlasManager()
  86 {
  87 }
  88
  89 void FixedTextureAtlasManager::CreateNewTexture()
  90 {
  91     int nTextureWidth = mWidthFactor  * mSubTextureSize;
  92     int nTextureHeight = mHeightFactor * mSubTextureSize;
  93     maFixedTextures.push_back(o3tl::make_unique<FixedTexture>(nTextureWidth, nTextureHeight, mWidthFactor * mHeightFactor));
  94 }
  95
  96 OpenGLTexture FixedTextureAtlasManager::Reserve(int nWidth, int nHeight)
  97 {
  98     FixedTexture* pFixedTexture = nullptr;
  99
 100     auto funFreeSlot = [] (std::unique_ptr<FixedTexture>& inFixedTexture)
 101     {
 102         return inFixedTexture->mnFreeSlots > 0;
 103     };
 104
 105     auto it = std::find_if(maFixedTextures.begin(), maFixedTextures.end(), funFreeSlot);
 106
 107     if (it != maFixedTextures.end())
 108     {
 109         pFixedTexture = (*it).get();
 110     }
 111     else
 112     {
 113         CreateNewTexture();
 114         pFixedTexture = maFixedTextures.back().get();
 115     }
 116
 117     int nSlot = pFixedTexture->findAndAllocateFreeSlot();
 118
 119     // Calculate coordinates in texture
 120     int nX = (nSlot % mWidthFactor) * mSubTextureSize;
 121     int nY = (nSlot / mWidthFactor) * mSubTextureSize;
 122
 123     tools::Rectangle aRectangle(Point(nX, nY), Size(nWidth, nHeight));
 124
 125     return OpenGLTexture(pFixedTexture->mpTexture, aRectangle, nSlot);
 126 }
 127
 128 OpenGLTexture FixedTextureAtlasManager::InsertBuffer(int nWidth, int nHeight, int nFormat, int nType, sal_uInt8 const * pData)
 129 {
 130     OpenGLTexture aTexture = Reserve(nWidth, nHeight);
 131     if (pData == nullptr)
 132         return aTexture;
 133
 134     aTexture.CopyData(nWidth, nHeight, nFormat, nType, pData);
 135
 136     return aTexture;
 137 }
 138
 139 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */