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 <sal/config.h>
  12 #include <vcl/opengl/OpenGLContext.hxx>
  13 #include <vcl/opengl/OpenGLHelper.hxx>
  14
  15 #include "opengl/framebuffer.hxx"
  16 #include "opengl/texture.hxx"
  17
  18 #include "opengl/FixedTextureAtlas.hxx"
  19
  20 #include <o3tl/make_unique.hxx>
  21
  22 struct FixedTexture
  23 {
  24     ImplOpenGLTexture* mpTexture;
  25     int mnFreeSlots;
  26     std::vector<bool> maAllocatedSlots;
  27
  28     FixedTexture(int nTextureWidth, int nTextureHeight, int nNumberOfSlots)
  29         : mpTexture(new ImplOpenGLTexture(nTextureWidth, nTextureHeight, true))
  30         , mnFreeSlots(nNumberOfSlots)
  31         , maAllocatedSlots(nNumberOfSlots, false)
  32     {
  33         auto aDeallocateFunction = [this] (int nSlotNumber)
  34         {
  35             deallocateSlot(nSlotNumber);
  36         };
  37
  38         mpTexture->SetSlotDeallocateCallback(aDeallocateFunction);
  39         mpTexture->InitializeSlotMechanism(nNumberOfSlots);
  40     }
  41
  42     ~FixedTexture()
  43     {
  44         mpTexture->ResetSlotDeallocateCallback();
  45         mpTexture->DecreaseRefCount(-1);
  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
  74 FixedTextureAtlasManager::FixedTextureAtlasManager(int nWidthFactor, int nHeightFactor, int nSubTextureSize)
  75     : mWidthFactor(nWidthFactor)
  76     , mHeightFactor(nHeightFactor)
  77     , mSubTextureSize(nSubTextureSize)
  78 {
  79 }
  80
  81 FixedTextureAtlasManager::~FixedTextureAtlasManager()
  82 {
  83 }
  84
  85 void FixedTextureAtlasManager::CreateNewTexture()
  86 {
  87     int nTextureWidth = mWidthFactor  * mSubTextureSize;
  88     int nTextureHeight = mHeightFactor * mSubTextureSize;
  89     maFixedTextures.push_back(o3tl::make_unique<FixedTexture>(nTextureWidth, nTextureHeight, mWidthFactor * mHeightFactor));
  90 }
  91
  92 OpenGLTexture FixedTextureAtlasManager::Reserve(int nWidth, int nHeight)
  93 {
  94     FixedTexture* pFixedTexture = nullptr;
  95
  96     auto funFreeSlot = [] (std::unique_ptr<FixedTexture>& inFixedTexture)
  97     {
  98         return inFixedTexture->mnFreeSlots > 0;
  99     };
 100
 101     auto it = std::find_if(maFixedTextures.begin(), maFixedTextures.end(), funFreeSlot);
 102
 103     if (it != maFixedTextures.end())
 104     {
 105         pFixedTexture = (*it).get();
 106     }
 107     else
 108     {
 109         CreateNewTexture();
 110         pFixedTexture = maFixedTextures.back().get();
 111     }
 112
 113     int nSlot = pFixedTexture->findAndAllocateFreeSlot();
 114
 115     // Calculate coordinates in texture
 116     int nX = (nSlot % mWidthFactor) * mSubTextureSize;
 117     int nY = (nSlot / mWidthFactor) * mSubTextureSize;
 118
 119     Rectangle aRectangle(Point(nX, nY), Size(nWidth, nHeight));
 120
 121     return OpenGLTexture(pFixedTexture->mpTexture, aRectangle, nSlot);
 122 }
 123
 124 OpenGLTexture FixedTextureAtlasManager::InsertBuffer(int nWidth, int nHeight, int nFormat, int nType, sal_uInt8* pData)
 125 {
 126     OpenGLTexture aTexture = Reserve(nWidth, nHeight);
 127     if (pData == nullptr)
 128         return aTexture;
 129
 130     aTexture.CopyData(nWidth, nHeight, nFormat, nType, pData);
 131
 132     return aTexture;
 133 }
 134
 135 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */