環形緩衝佇列技術應用例項

png解析度1080x800

【方案2】提前把所有png載入到記憶體，並且繪製成qpixmap

用vector實現環形佇列，定義乙個qpixmap型別的qvector容器，用於儲存位圖影象。

qvectorslicebuffer;

#define slicedatabufferlength 50

int wsliceindextoread = 0;

預先從磁碟載入位圖，填滿緩衝區

slicebuffer.clear();

for (int i = 0; i < slicedatabufferlength; i++)
wsliceindextoread = slicedatabufferlength;

if (m_writebufferthread)

m_writebufferthread = new qthread();
m_writebufferobj->movetothread(m_writebufferthread);
connect(m_writebufferthread, &qthread::finished, m_writebufferthread, &qobject::deletelater);
connect(m_writebufferthread, &qthread::finished, m_writebufferobj, &qobject::deletelater);
connect(this, &mainwindow::startwritebuffer, m_writebufferobj, &writeslicebufferthreadobject::writebuffer);
connect(m_writebufferobj, &writeslicebufferthreadobject::message, this, &mainwindow::receivemessage);
m_writebufferthread->start();

void writeslicebufferthreadobject::writebuffer()

}}

void mainwindow::startbuildthread()

m_buildthread = new qthread();
m_buildobj->movetothread(m_buildthread);
connect(m_buildthread, &qthread::finished, m_buildthread, &qobject::deletelater);
connect(m_buildthread, &qthread::finished, m_buildobj, &qobject::deletelater);connect(this, &mainwindow::startprint, m_buildobj, &printbuildthreadobject::buildrun);/*connect(m_buildobj, &printbuildthreadobject::message, this, &mainwindow::receivemessage);
connect(m_buildobj, &printbuildthreadobject::progress, this, &mainwindow::updateprogress);
connect(m_buildobj, &printbuildthreadobject::complete, this, &mainwindow::completebuild);*/		
m_buildthread->start();
}

//列印執行緒設定

if (m_buildobj)

void printbuildthreadobject::buildrun()

qfile file(m_gcodefile);
if (!file.open(qfile::readonly | qfile::text))
qtextstream in(&file);
large_integer  large_interger;
double dff;
__int64  c0,c1, c2, c3 = 0,c4;
queryperformancefrequency(&large_interger);
dff = large_interger.quadpart;
queryperformancecounter(&large_interger);
c0 = large_interger.quadpart;
singleton::getinstance()->m_cancontinue = true;
while (!in.atend())
qstring line;
if (singleton::getinstance()->m_cancontinue)
line = in.readline();
else
line = "idle";
if (line.startswith(";"))
else if (line.startswith(";"))
}else if (line.startswith("g1"))
delete sendbuffer;
//emit message(qstring::fromlocal8bit("%1:已傳送g1命令").arg(singleton::getcurrenttime()));
queryperformancecounter(&large_interger);
c2 = large_interger.quadpart;
if (c3 != 0)
//qdebug() << tr("time intevl:%1").arg((c2 - c3) * 1000 / dff);
emit message(tr("time intevl:%1").arg((c2 - c3) * 1000 / dff));
c3 = c2;
}	}queryperformancecounter(&large_interger);
c4 = large_interger.quadpart;
int secs = (c4 - c0) * 1000 / dff / 1000;
qstring slaspetime = tr("total time:%1 min %2 sec").arg(secs / 60).arg(secs % 60);
emit message(slaspetime);
emit complete();
file.close();
}

void mainwindow::updateprogress(int value)

//m_pic->showmaximized();
}

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