Fisherman with Phong...

[RomeoJGuy]

I thought this looked really good for Source so I share with you fisherman with custom phong effects added.

http://img91.imageshack.us/img91/515/lightwarptest1si9.jpg

 

[eraser]

Looks great. More shots?

 

[Que-Ever]

I have no idea what a "phong" is but it sounds dirty. That's a nice picture you've got there though.

 

[RomeoJGuy]

http://img245.imageshack.us/img245/8329/fisher1um5.jpg

http://img156.imageshack.us/img156/9254/fisher2fa3.jpg

Phong is a new shading technique that allows specularity to be based on two local lights at once instead of static cubemaps. I used custom exponent maps to get the effect just right. It is the same effects noticed on Alyx. It supports a fresnel effect which can be remapped allowing for a strong rim lighting effect.

http://en.wikipedia.org/wiki/Phong_reflection_model

 

[Para]

Phong as a shading model is actually very old. It's of course new in Source

And those pictures look crappy. I mean, the light seems to propagate through the whole head causing an erroneous sub surface scattering effect which makes the fisherman look both wrinkless and blank. And on top of that IIRC skin is NOT a Phong surface at all (I think it was more of a Lambertian one?)

 

[Cypher19]

Phong as a shading model is actually very old. It's of course new in Source

For more information on that, it was developed in something like the mid 70s. It's also one of the more basic and primitive lighting models by today's standards, so to be honest I'm extremely baffled as to why Valve felt it was even worth mentioning when they added it for Ep1.

And on top of that IIRC skin is NOT a Phong surface at all (I think it was more of a Lambertian one?)

Actually, skin, with the right data set, is far more closer to Phong lighting than Lambertian. Most of the time, skin doesn't reflect much light in a Phong style, but if you, say, hold your arm up so that a bright light source, your arm, and your eye are basically along the same direction, you'll find that there is a reflectance similar to Phong lighting. It's just that the Fresnel term of lighting on skin is very low when viewed head-on and only moderate when viewed edge-on, so the sharper reflection is rarely noticed.

 

[RomeoJGuy]

I suppose they mentioned it because its far better looking than cubemap refelection to do specularity for everything. Most surfaces do not have smooth enough surfaces to have cubemap specularity.

And I am aware its not new, it even says so in the wiki link. Of course I meant to source.

And I disagree. Although the other 2 are bugged I was testing lightwarp which is not something for models, but the first one is more accurate than previously available. Hold you hand up so its level with your eyes and look at it in the direction of window, it will reflect the bright sunlight off it. My fresnel ranges are all less than 0.5 except on the z which is from 2-4 for the different textures so that rim lighting is a little stronger.

edit: and Cypher you are correct. In the new shader sdk it is handled by a helper function named skin_helper, maybe they plan to add more skin effects like Sub-Surface Scattering.

 

[Acepilotf14]

Phong>Thong.
Pong>Thong.
Me>Thong.
Que-Ever<Thong.

 

[Para]

Actually, skin, with the right data set, is far more closer to Phong lighting than Lambertian. Most of the time, skin doesn't reflect much light in a Phong style, but if you, say, hold your arm up so that a bright light source, your arm, and your eye are basically along the same direction, you'll find that there is a reflectance similar to Phong lighting. It's just that the Fresnel term of lighting on skin is very low when viewed head-on and only moderate when viewed edge-on, so the sharper reflection is rarely noticed.

Hmmh. Would maybe Blinn or even Cook-Torrance be more appropriate for skin shading then?

The best solution of course would be true IOR materials but I kinda doubt we're gonna see those in real time any time soon...

 

[bigburpco]

Phong>Thong.
Pong>Thong.
Me>Thong.
Que-Ever<Thong.

Everybody>You