Documentation for neon, word and metric caching in README.in
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--enable-cpu-neon
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This enables support for the Arm Cortex-A8 and later Neon register
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set. In particular it will use neon optimised code for rotations and
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drawing with the software engines. Open GL based renderers will gain
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nothing from the use of neon.
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To use neon with gcc-4.4 you need a post-2009 gcc and options
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something like: -mcpu=cortex-a8 -mfloat-abi=softfp -mfpu=neon
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Note that this slightly slows down non-optimised parts of evas but
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the gains in drawing are more then worth it overall.
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This is enabled by default, and turns off if a small test program is
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unable to compile.
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Performance is at least 50%, and in some real world tests approaches
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100%.
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If you have any issues with neon, please report them to either the
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edevel mailing list or Brett Nash <nash@nash.id.uau>
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--enable-word-cache
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Cache rendered words and draw them as a single object, instead of
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individual characters. This is a big gain for things like neon which
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draw large runs effectively.
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However it is useless on GL and similar backends as the cost in
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sending a word sized texture kills the performance gain (and GL is
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pretty good at drawing lots of small things anyway).
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By default words (strings) of more then 50 characters are not cached.
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The system caches 40 words by default, but this can be changed by
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setting EVAS_WORD_CACHE_MAX_WORDS to another number. Setting it to 0
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will disable word-cache at run time.
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Text based benchmarks are 50-100% quicker.
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If you have any issues with word caching, please report them to either
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the edevel mailing list or Brett Nash <nash@nash.id.uau>
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For GL see metric caching...
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--enable-metric-cache
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Metric caching saves character metrics between characters in words.
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This enables it to render words much quicker as it avoids things like
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space calculations and kerning calculation.
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The cache seize is also controlled by EVAS_WORD_CACHE_MAX_WORDS
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It is useful for GL in particular, although software engines do get
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some gain.
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Generally it is recommended you enable either word or metric caching,
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depending on your engine use. If you are using software, enable word
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caching (and neon on arm if you can), for GL, turn on metric caching.
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If you have any issues with metric caching, please report them to either
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the edevel mailing list or Brett Nash <nash@nash.id.uau>
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------------------------------------------------------------------------------
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------------------------------------------------------------------------------
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COMPILING AND INSTALLING:
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COMPILING AND INSTALLING:
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