Lars Gullik Bjønnes wrote:
> | Note that there is room for improvement in our fontcache which uses a
> | std::map. A vector will probably not use too much memory (for 8bit
> | fonts) and be much faster.
> 
> It will not be 8bit fonts.
> 
> We should use a unordered_map and fallback to map if that is not
> available.

Here new numbers, better numbers because I don't use QTimer
any more but clock() which gives better results.

There are to cases: filling cash (scrolling down)
and reading (down, timer reset  and then up+down):

               Filling          Reading
           Guide    Tutorial    Tutorial
int[256]     11         8           5
QHash        12        14           9
std::map     16        16          10
Qt           75        70          70

in % of drawText, lesser is better,
error +- 3-6 (?)

And the result: all is better than not caching.
The fastest is int[256], who wonders?
QHash is a little bit faster than std::map.

I wonder about Qt, seems they have a worse cache.

Peter


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