Bug reading gray PNG

> On 1/6/2011 11:20 PM, Javier Díaz Reinoso wrote:
>> On 06/01/2011, at 17:02, Andreas Raab wrote:
>>
>>> On 1/6/2011 10:53 PM, Javier Díaz Reinoso wrote:
>>>> Fail with a 217x125 gray PNG in PNGReadWriter>>copyPixelsGray:, reverting to the previous version works.
>>>
>>> Can you share the file you're using? Even better, write a test that illustrates the failure?
>>>
>>> Thanks,
>>>  - Andreas
>>>
>> Is not the image, is bad aritmethic, try with thisScanline ->  217:
>
> But do you have an example PNG file that causes the problem to happen? I'm sure the issue it's obvious to you but it's not for me.
>
> Cheers,
>  - Andreas
>
>>> 0 to: thisScanline size - 1 // 4 do: [ :i |
>>> | ii word |
>>> ii := i * 4.
>>> "This somewhat weird mixture of (#* and #+) with (#bitShift: and #bitOr:)
>>> is to make use of faster arithmetic bytecodes, but not of slow largeintegers."
>>> word :=
>>> (((thisScanline at: ii + 1) * 256 +
>>> (thisScanline at: ii + 2) * 256 +
>>> (thisScanline at: ii + 3)) bitShift: 8) bitOr:
>>> (thisScanline at: ii + 4).<======
>>
>>
>
>