On 21 November 2013 21:27, Hilaire Fernandes <hilaire.fernandes@gmail.com> wrote:

Le 21/11/2013 08:21, St��phane Ducasse a ��crit :

>
> On Nov 20, 2013, at 4:54 PM, Hilaire Fernandes <hilaire.fernandes@gmail.com> wrote:
>
>> Hello,
>>
>> In Pharo 2.0 (true in 1.4 as well), it looks PNG bitmap are wrongly
>> rotated or scaled when they contain alpha transparency.
>>
>> In the example bellow with the joined bitmap, the alpha gray color are
>> rendered darker when the imagemorph is scaled or rotated.
>>
>> Sqeak does not suffer this problem
>
> hilaire may be you should have a look at the changes made in the graphics package

I took at look on the list, did not find anything yet

not directly, right. But since symptoms are similar, i think this is most probably the same case.

(and your digging shown that we actually having separate rule for

premultiplied alpha blend, which i could use for correctly transferring/blending

cairo surface pixels in Forms)

��

Hilaire

> of squeak to identify the change.
> We should have more tests.
>
> Stef
>>
>>
>> | dir morph transform form|
>> dir := FileSystem disk workingDirectory parent.
>> morph := (ImageReadWriter formFromFileNamed: (dir / 'bubble.png')
>> fullName) asMorph.
>> transform := TransformationMorph new asFlexOf: morph.
>> transform smoothingOn ; angle: Float pi / 3; scale: 1.
>> transform openInWorld
>>
>>
>> Thanks
>>
>> Hilaire
>>
>>
>> --
>> Dr. Geo http://drgeo.eu
>> <bubble.png>
>
>
>

--
Dr. Geo http://drgeo.eu

--
Best regards,
Igor Stasenko.