Re: Question on transparent camera transformed objects.

[Frank C. <dev...@ch...>]

On 28-Sep-04, at 1:09 PM, Peter Michelsen wrote:

> On 28 Sep 2004, at 17:13, Frank Condello wrote:
>
>> On 28-Sep-04, at 11:09 AM, Peter Michelsen wrote:
>>
>>> I have setup all the objects needed to create this effect, including  
>>> four polygons with; an attribute of diffuse gray colour ( 0xAFFF)  
>>> and an attribute of transparency colour ( 0xAFFF ) and no other  
>>> attributes.
>>>
>>> Now the problem, as the camera rotate around the polygons colour  
>>> changes. The reason is that the polygons are real 3D objects in  
>>> Quesa space so are effected by the sun light. ( tested by turning  
>>> the sun off e.g. the directional light ).
>>>
>>> We normally overcome this problem by submitting objects before the  
>>> view light style is added but as the polygons are transparent this  
>>> trick does not work.
>>
>> It's probably safer to put that geometry into a display group with a  
>> null shader, but depending on which version of Quesa your using you  
>> may be seeing this bug:  
>> <http://sourceforge.net/tracker/index.php? 
>> func=detail&aid=967773&group_id=45158&atid=442052>
>
> I tried this but it had no effect as the objects are transparent.....  
> and I guess ( from testing ) use the last style illumination style set  
> in the submit loop. ( does this sound right or am I way of base? ).

That's correct-  the illumination of the last solid object is errantly  
maintained for the entire transparent pass. The bug report linked above  
includes a bit of a workaround if your're using the CVS source.

Frank.