Can we talk about lights in Wings3D?

[Egyt]

Infinite: emits parallel rays, lightsource located at a very long distance have the properties of infinite lights. ie the sun.

Pointlight: emits rays in all directions, ie lightbulb.

Spotlight: Yes like flashlight, emits rays in a defined area/direction, default a cone.

Ambient: Lights everything up in a flat way, If ambient set to 50% grey, nothing in the scene can appear darker than 50% grey.

Dont quote me on anything, this is what I think. ty.

[negative9]

...by Parallel rays? IE Parallel to what? To the Object face you point it at?

And on Ambient, you mean basicly whether or not there can be a shadow or if the surrounding light souces are to great in all directions to have a shadow?

I found these diffentions on a site regarding VRML, are these prety acurate?

Diffuse - colour of object
Specular - highlight colour on shiny objects
Emissive - glow colour
Ambient - intensity
Shininess - changes the size of the highlight


//negative9//

[JamesMK]

...by Parallel rays? IE Parallel to what? To the Object face you point it at?

It means that the rays are parallel to eachother. Think of a light as sending out a huge bundle of lightrays. In a spotlight, classic non-parallel type, the rays are considered to radiate from a single point (the lightsource itself) radially in all directions, but limited to the coneangle. Parallel rays on the other hand are considered to be... ah... parallel - think of it as a cable or a cylinder of lightrays rather than a "starburst" type of emission.

And on Ambient, you mean basicly whether or not there can be a shadow or if the surrounding light souces are to great in all directions to have a shadow?

There can be shadows, but they would never be darker than the power of the ambient light. This, of course, requires a shadowcasting lightsource somewhere. An ambient lightsource is one that shines an equal amount of light on ALL surfaces, no matter where they are, if they are occluded by other surfaces and regardless of their angle relative to the lightsource in question. In other words, a very bad lightsource that one should stay far away from unless for pure modeling purposes.

BTW: These things are not in any way Wings-specific. It is general 3D terminology.

[negative9]

BTW: These things are not in any way Wings-specific. It is general 3D terminology.

Yeah, I knew that, I just could't find any information on it, so I'm trying to compile a quick reference to what these diffrent lighting properties do.

This is what I've compiled so far, corrections are welcome - and encouraged.

INFINATE - light shining to a specific direction but where distance to the light isn’t important.

POINT - light light coming from a certain point in space illuminating in all directions (like a light bulb)

SPOT - a focused beam of light that can be pointed at objects or areas, like a theatre spotlight; distance from the light to the object is taken into account.

AMBIENT - general lighting that illuminates all objects in the scene

And for properties

DIFFUSE - colour of light
SPECULAR - highlight colour on shiny objects
EMISSIVE - glow colour
AMBIENT - intensity
SHININESS - changes the size of the highlight, and specular glow
ATTUNITION - how far a lights reach is
LINEAR - whether the light source is directional
QUADRADIC - light emmits in all directions, like a torch

[JamesMK]

Some adjustments ;)

INFINITE - Shines in a specific direction, but it is calculated as if it was placed infinitely far away from your scene - hence it will appear to illuminate all objects in such a way that they get the same shading angle, so to speak.

AMBIENT - Does not take the angle into account. All surfaces are equally illuminated no matter where they are or where their normal is pointing.

EMISSIVE - This is not a property of lights, but a surface property that defines the self-illumiation of the object - i.e. the amount and color of emission or luminance. It cannot illuminate other objects (unless you render in a GI-renderer), but it can make an object visible even if there are no lights in the scene or if the object is hidden in a shadow.

AMBIENT - This is the color of the ambient component (see above)of a lightsource. By default set to black = no ambient amount.

SHININESS - Again, this is not a light property, but a surface property controlling the specular falloff and value.

ATTENUATION - The collective term for light falloff (how the light energy decreases over a certain distance) and in Wings this can be set to either LINEAR (meaning that the energy decreases linearly over its set range), or QUADRADIC (meaning that the energy decreases in an quadratic exponential fashion over its set range)

It's important to realise that the lights in Wings are simply wrappers for standard OpenGL lights (if I'm not totally misinformed) - and that most rendering packages handle lights a bit differently.

[negative9]

The pieces of the puzzle are all coming together. I'm starting to see 'the light!'

Pardon the pun.

Okay, I'm going to recompile what I have in a nice looking page layout (a webpage someplace) to break it all down - yet again, but with pretty pictures.

Once finished can you (jamesMK, or Egyt) look at it, and possible post any modifications needed here?

Thanks in advanced.

//negative9//

[negative9]

I've posted all the compiled infomation on LIGHTS IN WINGS 3D here:
http://www.geocities.com/n2geoff/wings3d/lights.html

It is also A Wings3D website (static) I'm working on, but Have along way to go. Only a few links work as of right now.

NEXT I want to Focus on Materials.

Thanx

//negative9//

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