The January 2012 Tutorial Discussion

[jvila]

Hi Javier—

I'm sorry you're having a not-fun time with this! Frances was able to do something clever and attractive by studying the images, by the way.

There is only one light, but in real life, there is more than one source of illumination, indirect lighting, also call ambient lighting—light that comes from bouncing off the surroundings, and that is why the faces closest to the floor in the image are lighter than you'd expect them to be...they are getting light from the floor.

I will try to make this example easier here, and if I fail 1.) I'm not a good teacher and 2.) give up on this one

Here is the top view of the scene, and the camera's view including the area-type light object. The arrow in the top images indicates where the light is directed, as does the orange arrow on the light itself. I also rendered the same scene with no textures.



Are these good hints to work from?

hi Gare,
I'm not saying I'm not having a fun time actually it is really fun, the more challenge it is the more interesting is to me.
You are very polite when you avoided writing the 3rd option if you fail and that option is me hehehehehehe.
According the last example, if I look at the light source it is pointing in one direction and the shadow of the object is not pointing in the same direction actually it is pointing towards right
Trying to be clearer I'm uploading your jpg with an arrow indicating the direction of the light and in yellow where I think the shadow should be (that's the problem I always face, I think the shadow is located on another place).

As I said it is very interesting, entertaining and above all very important to achieve better results.

Best regards and thank you very much.

[Gare]

What is probably confusing is that the shadow is very soft at the edges, and also that shadows are what?

Shadows are NOT just areas where a single light source is stopped by an object. A shadow also happens, in addition to—if you understand what I mean—where naturally-occurring light, ambient light, cannot reach a surface.

Yes, objects cast shadows, but darker areas, which we might not even call a shadow, occur when light cannot get to an area.

This is scientifically called "ambient occlusion", and this is what my modeling program is doing.

Also, the front of the icosahedron is pointed and it, too casts a shadow, although our eyes fool us because a 2D scene flattens this 3rd dimension and we don't expect it to cast a shadow.

Let me grossly simplify the scene, okay? No tricky ambient lighting, nit very photorealistic, though...



-g-

[Drwyd]

Well here goes, this is my attempt at a isocihidiron, icosihidroon, ihosicedron ......... that funny shape.

[Gare]

THAT is TOTALLY wonderful, Drwyd!

You nailed the shading, took the trouble to soften the edges, your lighting and shading is way cool!

And I don't know how to spell "icosahedron', either. It's a "polyhedron", or "polyunsaturated", usually.

My Best,

Gary

[Drwyd]

Thank you Gary

It still feels a bit "floaty" to me. I may add a textured ground to help land it.

[Gare]

What might also help the anchor is deepening the shadow closest to the object. Shadows, more evident on hard surfaces outdoors than soft, ambient lit ones, have a shadow umbra and a penumbra; I refer you to Wikipedia's entry on it.

Also, to keep it from floating, put something heavy, like a garden brick on it.

—Gary

[jvila]

WOW everyday We learn something new, shadows are like languages It gets complicated when you have to learn it when your old, until now shadows were just shadows, now I don't dare to say what they are .

Our ignorance carries us safe along the road hehehehehe.

I'm keep on reading about this topic, I'm still under a very dark shade

[Drwyd]

2nd attempt