GX2_GUI_Template/src/gui/GuiImageAsync.cpp

/****************************************************************************
 * Copyright (C) 2015 Dimok
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 ****************************************************************************/
#include <unistd.h>
#include "GuiImageAsync.h"
#include "fs/fs_utils.h"

std::vector<GuiImageAsync *> GuiImageAsync::imageQueue;
CThread * GuiImageAsync::pThread = NULL;
CMutex * GuiImageAsync::pMutex = NULL;
u32 GuiImageAsync::threadRefCounter = 0;
bool GuiImageAsync::bExitRequested = false;
GuiImageAsync * GuiImageAsync::pInUse = NULL;

GuiImageAsync::GuiImageAsync(const u8 *imageBuffer, const u32 & imageBufferSize, GuiImageData * preloadImg)
    : GuiImage(preloadImg)
	, imgData(NULL)
	, imgBuffer(imageBuffer)
	, imgBufferSize(imageBufferSize)
{
	threadInit();
	threadAddImage(this);
}

GuiImageAsync::GuiImageAsync(const std::string & file, GuiImageData * preloadImg)
    : GuiImage(preloadImg)
	, imgData(NULL)
	, filename(file)
	, imgBuffer(NULL)
	, imgBufferSize(0)
{
	threadInit();
	threadAddImage(this);
}

GuiImageAsync::~GuiImageAsync()
{
	threadRemoveImage(this);
	while(pInUse == this)
        usleep(1000);

	if (imgData)
        delete imgData;

    threadExit();
}

void GuiImageAsync::threadAddImage(GuiImageAsync *Image)
{
    pMutex->lock();
	imageQueue.push_back(Image);
    pMutex->unlock();
	pThread->resumeThread();
}

void GuiImageAsync::threadRemoveImage(GuiImageAsync *image)
{
    pMutex->lock();
	for(u32 i = 0; i < imageQueue.size(); ++i)
	{
		if(imageQueue[i] == image)
		{
			imageQueue.erase(imageQueue.begin() + i);
			break;
		}
	}
    pMutex->unlock();
}

void GuiImageAsync::clearQueue()
{
    pMutex->lock();
	imageQueue.clear();
    pMutex->unlock();
}

void GuiImageAsync::guiImageAsyncThread(CThread *thread, void *arg)
{
	while(!bExitRequested)
	{
        if(imageQueue.empty() && !bExitRequested)
            pThread->suspendThread();

		if(!imageQueue.empty() && !bExitRequested)
		{
            pMutex->lock();
			pInUse = imageQueue.front();
			imageQueue.erase(imageQueue.begin());
            pMutex->unlock();

			if (!pInUse)
				continue;


            if(pInUse->imgBuffer && pInUse->imgBufferSize)
            {
                pInUse->imgData = new GuiImageData(pInUse->imgBuffer, pInUse->imgBufferSize);
            }
            else
            {
                u8 *buffer = NULL;
                u32 bufferSize = 0;

                int iResult = LoadFileToMem(pInUse->filename.c_str(), &buffer, &bufferSize);
                if(iResult > 0)
                {
                    pInUse->imgData = new GuiImageData(buffer, bufferSize, GX2_TEX_CLAMP_MODE_MIRROR);

                    //! free original image buffer which is converted to texture now and not needed anymore
                    free(buffer);
                }
            }

            if(pInUse->imgData)
            {
                if(pInUse->imgData->getTexture())
                {
                    pInUse->width = pInUse->imgData->getWidth();
                    pInUse->height = pInUse->imgData->getHeight();
                    pInUse->imageData = pInUse->imgData;
                }
                else
                {
                    delete pInUse->imgData;
                    pInUse->imgData = NULL;
                }
            }

			pInUse = NULL;
		}
	}
}

void GuiImageAsync::threadInit()
{
	if (pThread == NULL)
    {
        bExitRequested = false;
        pMutex = new CMutex();
	    pThread = CThread::create(GuiImageAsync::guiImageAsyncThread, NULL, CThread::eAttributeAffCore1 | CThread::eAttributePinnedAff, 10);
		pThread->resumeThread();
    }

    ++threadRefCounter;
}

void GuiImageAsync::threadExit()
{
    --threadRefCounter;

	if((threadRefCounter == 0) && (pThread != NULL))
	{
	    bExitRequested = true;
        delete pThread;
        delete pMutex;
        pThread = NULL;
        pMutex = NULL;
	}
}