-3
我正在做一些实时的东西,我需要很多速度。但在我的代码,我有这样的:C++优化
float maxdepth;
uint32_t faceindex;
for (uint32_t tr_iterator = 0; tr_iterator < facesNum-1; tr_iterator++)
{
maxdepth = VXTrisDepth[tr_iterator];
faceindex = tr_iterator;
uint32_t tr_literator = 3*tr_iterator;
uint32_t facelindex = 3*faceindex;
for (uint32_t tr_titerator = tr_iterator+1; tr_titerator < facesNum; tr_titerator++)
{
float depth = VXTrisDepth[tr_titerator];
if (depth > maxdepth)
{
maxdepth = depth;
faceindex = tr_titerator;
}
}
Vei2 itmpx = trs[tr_literator+0];
trs[tr_literator+0] = trs[facelindex+0];
trs[facelindex+0] = itmpx;
itmpx = trs[tr_literator+1];
trs[tr_literator+1] = trs[facelindex+1];
trs[facelindex+1] = itmpx;
itmpx = trs[tr_literator+2];
trs[tr_literator+2] = trs[facelindex+2];
trs[facelindex+2] = itmpx;
float id = VXTrisDepth[tr_iterator];
VXTrisDepth[tr_iterator] = VXTrisDepth[faceindex];
VXTrisDepth[faceindex] = id;
}
VXTrisDepth只是浮动的数组,faceindex是一个uint32_t的,是一个很大的数字,TRS是Vei2的数组,Vei2仅仅是一个整数二维矢量。 问题是,当我们在facenum中有类似16074的东西时,这个循环需要700毫秒才能在我的计算机上运行,而且这太方便了,有没有优化的想法?
你尝试过'-O3'开关吗? –
尝试在你有tmp变量的地方使用std :: swap – JLev
可能的优化是将第二个循环移出第一个循环,“2nd”循环为每个tr_titerator构建一个maxdepth和faceindex矢量, 1st循环使用它来代替。 – megabyte1024