View Full Version : Texturing Help -spec/render

05 May 2003, 05:48 AM
ok guys this is my first attemp at texturing so please bare with ,
ok i am using phong shader , i plugged this into it as the spec map (scratches on surface) but when i do a render they DONT show , i dont really know what im doing here , so any suggestions will help , heres the spec : is this even painted correctly?or is phong shader good for
thx in advance for any help

05 May 2003, 06:31 AM
You've got your scratches image inverted.

White means shiny, black means dull. So as it is you've got 85% dull with some shiny scratches!

05 May 2003, 06:54 AM
thx joz , will try that now

05 May 2003, 07:00 AM
got any tips on what kind of shaders, maps etc i should be using, im tryin to get a realistic metal chipped worn out surface , its going to be rendered in mental ray

05 May 2003, 07:11 AM
ok i inverted the spec map , so its all white with black scratches and still i see no scratches at rendering , did i miss something?

05 May 2003, 08:52 AM
If you remove that map from the specular color, do you see a highlight? Basically the map is simply saying that you can have a hightlight in the white areas. It won't automatically make them lighter. You might need to make the actual highlight larger (lower cosine power in phong shader).

Try applying that material to a sphere to see if the material is working. Unless they are really large, specular reflections don't often show up on flat surfaces, because they need to be facing just the right direction.

05 May 2003, 09:20 AM
Hehe yeah, everything victor said! :thumbsup:

05 May 2003, 09:50 AM
that worked perfect , altho im noticing depending on the angle . theres certain scratches i cant see , should i just throw the scratches on another map? diffuse/color? oh and btw thx alot for the help :)

05 May 2003, 05:22 AM
It all depends on the material you're trying for; you have to analyze it.
Would there be a change of color inside the scratch - apart from the highlight? If so, put that changed color there, in the color channel.
Would there be a noticeable bump? If so place a darker color there in the bump channel (darker means lower, lighter means higher.)
And so on through all the channels.
BTW I would definitely recommend adding some bevelled or rounded edges, it will be much easier to see specular effects then.

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