Re: filterRes

On Wed, 15 Jul 2009 04:26:59 +0200, Robert O'Callahan <> wrote:

> 2009/7/14 Dr. Olaf Hoffmann <>
>> another problem I observed for filterRes comparing the behaviour
>> of Opera and the adobe plugin is, what happens ich non-integers
>> are noted as attribute values.
>> Because filterRes is specified to be of the type
>> <number-optional-number>
>> such values as '0.5' or '4.2 4.8' are possible,
>> however the interpretation seems to be undefined
>> or is different in viewers. Opera seems to round
>> down non-integers, the adobe plugin rounds to
>> the nearest integer (I did not look into detail for
>> the case integer+0.5). This results in different
>> effects especially within animation to fade in/out
>> objects by changing the filterRes to small
>> numbers (continuously).
> We (Mozilla) round to the nearest integer, rounding 0.5 up to 1. I agree the
> spec need to specify the rounding method.

I can confirm that Opera truncates the filterRes values, i.e. rounds the values to the closest integer value towards zero.

Erik Dahlstrom, Core Technology Developer, Opera Software
Co-Chair, W3C SVG Working Group
Personal blog:

Received on Wednesday, 15 July 2009 10:52:27 UTC