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 struct FixedTexture
  21 {
  22     ImplOpenGLTexture* mpTexture;
  23     int mnFreeSlots;
  24     std::vector<bool> maAllocatedSlots;
  25
  26     FixedTexture(ImplOpenGLTexture* pTexture, int nNumberOfSlots)
  27         : mpTexture(pTexture)
  28         , mnFreeSlots(nNumberOfSlots)
  29         , maAllocatedSlots(nNumberOfSlots, false)
  30     {
  31         auto aDeallocateFunction = [this] (int nSlotNumber)
  32         {
  33             deallocateSlot(nSlotNumber);
  34         };
  35
  36         mpTexture->SetSlotDeallocateCallback(aDeallocateFunction);
  37         mpTexture->InitializeSlotMechanism(nNumberOfSlots);
  38     }
  39
  40     void allocateSlot(int nSlot)
  41     {
  42         maAllocatedSlots[nSlot] = true;
  43         mnFreeSlots--;
  44     }
  45
  46     void deallocateSlot(int nSlot)
  47     {
  48         maAllocatedSlots[nSlot] = false;
  49         mnFreeSlots++;
  50     }
  51
  52     int findAndAllocateFreeSlot()
  53     {
  54         for (size_t i = 0; i < maAllocatedSlots.size(); ++i)
  55         {
  56             if (!maAllocatedSlots[i])
  57             {
  58                 allocateSlot(i);
  59                 return i;
  60             }
  61         }
  62         return -1;
  63     }
  64 };
  65
  66 FixedTextureAtlasManager::FixedTextureAtlasManager(int nWidthFactor, int nHeightFactor, int nSubTextureSize)
  67     : mWidthFactor(nWidthFactor)
  68     , mHeightFactor(nHeightFactor)
  69     , mSubTextureSize(nSubTextureSize)
  70 {
  71 }
  72
  73 FixedTextureAtlasManager::~FixedTextureAtlasManager()
  74 {
  75     for (std::unique_ptr<FixedTexture>& pFixedTexture : maFixedTextures)
  76     {
  77         // Free texture early in VCL shutdown while we have a context.
  78         delete pFixedTexture->mpTexture;
  79     }
  80 }
  81
  82 void FixedTextureAtlasManager::CreateNewTexture()
  83 {
  84     int nTextureWidth = mWidthFactor  * mSubTextureSize;
  85     int nTextureHeight = mHeightFactor * mSubTextureSize;
  86     std::unique_ptr<FixedTexture> pFixedTexture(
  87                                     new FixedTexture(new ImplOpenGLTexture(nTextureWidth, nTextureHeight, true),
  88                                     mWidthFactor * mHeightFactor));
  89
  90     maFixedTextures.push_back(std::move(pFixedTexture));
  91 }
  92
  93 OpenGLTexture FixedTextureAtlasManager::Reserve(int nWidth, int nHeight)
  94 {
  95     FixedTexture* pFixedTexture = nullptr;
  96
  97     auto funFreeSlot = [] (std::unique_ptr<FixedTexture>& inFixedTexture)
  98     {
  99         return inFixedTexture->mnFreeSlots > 0;
 100     };
 101
 102     auto it = std::find_if(maFixedTextures.begin(), maFixedTextures.end(), funFreeSlot);
 103
 104     if (it != maFixedTextures.end())
 105     {
 106         pFixedTexture = (*it).get();
 107     }
 108     else
 109     {
 110         CreateNewTexture();
 111         pFixedTexture = maFixedTextures.back().get();
 112     }
 113
 114     int nSlot = pFixedTexture->findAndAllocateFreeSlot();
 115
 116     // Calculate coordinates in texture
 117     int nX = (nSlot % mWidthFactor) * mSubTextureSize;
 118     int nY = (nSlot / mWidthFactor) * mSubTextureSize;
 119
 120     Rectangle aRectangle(Point(nX, nY), Size(nWidth, nHeight));
 121
 122     return OpenGLTexture(pFixedTexture->mpTexture, aRectangle, nSlot);
 123 }
 124
 125 OpenGLTexture FixedTextureAtlasManager::InsertBuffer(int nWidth, int nHeight, int nFormat, int nType, sal_uInt8* pData)
 126 {
 127     OpenGLTexture aTexture = Reserve(nWidth, nHeight);
 128     if (pData == nullptr)
 129         return aTexture;
 130
 131     aTexture.CopyData(nWidth, nHeight, nFormat, nType, pData);
 132
 133     return aTexture;
 134 }
 135
 136 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */