>> my questions are 
>> 1. Do both modes (e.g. double and fixed) test if a sampled pixel center
>> is
>> inside the triangle, from the calculation i'm not sure. 

>Yes.

If both sample exact pixel center, why do they get different results, i
would expect the exact same triangle to be rasterized?
Just to check if we speak in the same terms, a pixel center is some int plus
half 
for example if x = 11.5 y = 4.5 is inside a triangle it will be rasterized.
I can't see from the code how Mesa checks exact pixel centers.

>> I know that Mesa doesnt exactly samples, it does some complicated setup
>> and
>> than scanline using that setup but if someone can describe in words how
>> this
>> correspands to sampling i would be most grateful.

>By "samples" do you mean point sampling or multisampling or something else?

by sampling i mean traversing pixel centers and checking using edge
functions for example to know if that exact point is inside a triangle or
not. 
Another question i have is about the code: what is the purpose of the "minus
half reduction" in thenext line from s_tritemp.h, does it have anything to
do with pixel centers?

const GLfixed fy0 = FloatToFixed(v0->attrib[FRAG_ATTRIB_WPOS][1] - 0.5F) &
snapMask;

-- 
View this message in context: 
http://www.nabble.com/tritemp.h-pixel-insideness-testing-tp22563214p22564277.html
Sent from the mesa3d-dev mailing list archive at Nabble.com.


------------------------------------------------------------------------------
Apps built with the Adobe(R) Flex(R) framework and Flex Builder(TM) are
powering Web 2.0 with engaging, cross-platform capabilities. Quickly and
easily build your RIAs with Flex Builder, the Eclipse(TM)based development
software that enables intelligent coding and step-through debugging.
Download the free 60 day trial. http://p.sf.net/sfu/www-adobe-com
_______________________________________________
Mesa3d-dev mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/mesa3d-dev

Reply via email to