A little font rendering speedup

> This is an image-side change, which makes a primitiveDisplayString to
> not fail because StrikeFontSet returns nil for (font
> characterToGlyphMap).
>
> Since the code, which using fast primitive looks like following:
>
>        self primDisplayString: aString from: startIndex to: stopIndex
>                        map: font characterToGlyphMap xTable: font xTable
>                        kern: kernDelta
>
> I thought, why one would return nil in ( font characterToGlyphMap ).
> Since #xTable in StrikeFontSet implemented as following:
>
> xTable
>        "Answer an Array of the left x-coordinate of characters in glyphs."
>
>        ^ (fontArray  at: 1) xTable.
>
> i think it is safe to do similar in characterToGlyphMap ,
> this allows the primitive to work w/o failure, because otherwise, if
> you look at implementation of
>
> primDisplayString: aString from: startIndex to: stopIndex map:
> glyphMap xTable: xTable kern: kernDelta
>
> in fallback code it does same thing again (and ignoring glyphMap at all, btw).
>
>
> To bench a difference, leave a couple of windows with text in world and then do:
>
> [10 timesRepeat: [World fullDrawOn: World assuredCanvas] ] timeToRun
>
> before change:
>
>  645
>
> after change:
>
>  545
>
> P.S. since i did this in a fresh pharo-10284-dev, where changesorter
> is completely broken(do you aware of it?), i filed out this method as
> .st file.
>
> --
> Best regards,
> Igor Stasenko AKA sig.
>
> _______________________________________________
> Pharo-project mailing list
> [hidden email]
> http://lists.gforge.inria.fr/cgi-bin/mailman/listinfo/pharo-project
>

> I put this on mantis, since i'm sure this applies to squeak3.10 and  
> Pharo both.
>
> http://bugs.squeak.org/view.php?id=7338
>
>
> ---------- Forwarded message ----------
> From: Igor Stasenko <[hidden email]>
> Date: 2009/4/19
> Subject: A little font rendering speedup
> To: Pharo Development <[hidden email]>
>
>
> This is an image-side change, which makes a primitiveDisplayString to
> not fail because StrikeFontSet returns nil for (font
> characterToGlyphMap).
>
> Since the code, which using fast primitive looks like following:
>
>        self primDisplayString: aString from: startIndex to: stopIndex
>                        map: font characterToGlyphMap xTable: font  
> xTable
>                        kern: kernDelta
>
> I thought, why one would return nil in ( font characterToGlyphMap ).
> Since #xTable in StrikeFontSet implemented as following:
>
> xTable
>        "Answer an Array of the left x-coordinate of characters in  
> glyphs."
>
>        ^ (fontArray  at: 1) xTable.
>
> i think it is safe to do similar in characterToGlyphMap ,
> this allows the primitive to work w/o failure, because otherwise, if
> you look at implementation of
>
> primDisplayString: aString from: startIndex to: stopIndex map:
> glyphMap xTable: xTable kern: kernDelta
>
> in fallback code it does same thing again (and ignoring glyphMap at  
> all, btw).
>
>
> To bench a difference, leave a couple of windows with text in world  
> and then do:
>
> [10 timesRepeat: [World fullDrawOn: World assuredCanvas] ] timeToRun
>
> before change:
>
>  645
>
> after change:
>
>  545
>
>
>
>
> --
> Best regards,
> Igor Stasenko AKA sig.
> <StrikeFontSet-characterToGlyphMap.st>

> Thanks, Igor,
>
> I created an entry in the Pharo tracker with a link to the Mantis
> entry to allow us to keep track of its integration into Pharo.
>
> http://code.google.com/p/pharo/issues/detail?id=758
>
> Cheers,
> Adrian
>
>
> http://code.google.com/p/pharo/issues/detail?id=758
> On Apr 19, 2009, at 15:36 , Igor Stasenko wrote:
>
>> I put this on mantis, since i'm sure this applies to squeak3.10 and
>> Pharo both.
>>
>> http://bugs.squeak.org/view.php?id=7338
>>
>>
>> ---------- Forwarded message ----------
>> From: Igor Stasenko <[hidden email]>
>> Date: 2009/4/19
>> Subject: A little font rendering speedup
>> To: Pharo Development <[hidden email]>
>>
>>
>> This is an image-side change, which makes a primitiveDisplayString to
>> not fail because StrikeFontSet returns nil for (font
>> characterToGlyphMap).
>>
>> Since the code, which using fast primitive looks like following:
>>
>>        self primDisplayString: aString from: startIndex to: stopIndex
>>                        map: font characterToGlyphMap xTable: font
>> xTable
>>                        kern: kernDelta
>>
>> I thought, why one would return nil in ( font characterToGlyphMap ).
>> Since #xTable in StrikeFontSet implemented as following:
>>
>> xTable
>>        "Answer an Array of the left x-coordinate of characters in
>> glyphs."
>>
>>        ^ (fontArray  at: 1) xTable.
>>
>> i think it is safe to do similar in characterToGlyphMap ,
>> this allows the primitive to work w/o failure, because otherwise, if
>> you look at implementation of
>>
>> primDisplayString: aString from: startIndex to: stopIndex map:
>> glyphMap xTable: xTable kern: kernDelta
>>
>> in fallback code it does same thing again (and ignoring glyphMap at
>> all, btw).
>>
>>
>> To bench a difference, leave a couple of windows with text in world
>> and then do:
>>
>> [10 timesRepeat: [World fullDrawOn: World assuredCanvas] ] timeToRun
>>
>> before change:
>>
>>  645
>>
>> after change:
>>
>>  545
>>
>>
>>
>>
>> --
>> Best regards,
>> Igor Stasenko AKA sig.
>> <StrikeFontSet-characterToGlyphMap.st>
>
>
> _______________________________________________
> Pharo-project mailing list
> [hidden email]
> http://lists.gforge.inria.fr/cgi-bin/mailman/listinfo/pharo-project
>