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cove
10-30-2014, 10:46 AM
Hi.
I have a query about the very usefull "Headlight" feature that gives you extra all round lighting
in Open GL.
I would like to be able to reproduce the same lighting using the lights in Lightwave.
Which lights eg. Area/spot
How many lights
How are the lights arranged.
Thanks for any advise given in reply.
Regards. KEN.

lertola2
10-30-2014, 02:02 PM
You could parent a distant light to the camera so that you will always have a light shining directly on your scene from the camera's point of view. I think that is similar to what headlight does. You could also turn up the ambient intensity on the light properties panel. This will give you light shining on your scene from all directions except no shadows.

prometheus
10-30-2014, 02:04 PM
That is a little of a pointless to aim for in terms of good lighting setup.

just add a point light just in front of the camera and move it a little above the camera, and it will in principle look almost the same.

But I wouldn´t set any scene up according to matching open gl headlight, but maybe you got a good reason for it? :)

Ask your self..what am I trying to render, and aim for the best lighting techniques in regards to that..wether it may be a 3 light setup, image based lighting/global illumination/radiosity or use area lights for product shots and interiors...or if
you should do exterior work and use distant lights or dome lights with radiosity etc.

Michael

Sensei
10-30-2014, 02:46 PM
Hi.
I have a query about the very usefull "Headlight" feature that gives you extra all round lighting
in Open GL.
I would like to be able to reproduce the same lighting using the lights in Lightwave.
Which lights eg. Area/spot
How many lights
How are the lights arranged.
Thanks for any advise given in reply.
Regards. KEN.

Use mine Headlight plugin from http://www.trueart.eu

Sensei
10-30-2014, 02:49 PM
That is a little of a pointless to aim for in terms of good lighting setup.

Nope. See example renders on website.
It's very nice. Better quality than Ambient Intensity.
But don't use 100% intensity.

See how it looks in anim-gif:
http://forums.newtek.com/attachment.php?attachmentid=125259&d=1414702942

One frame, normal area 100%,
Second frame, normal area 75%, headlight 25%

cove
10-31-2014, 07:45 AM
Thanks for your comments and advice.
As a result I can now change the lighting to get the effect im after.
The issue was this.
When you turn on the headlight and you have some upright oblongs and squares in the scene.
The edges of theses objects can be washed out by the headlight.
Also the headlight can appear very bright.
There are no controls associated with the headlight to change anything.
Hence my question here about an equivalent lighting set up.
Having tried out a few things ive found that simply changing the default light to an area light
and changing the ambient intensity to about 60% improves the edge aspect and the ambient control
allows you to control the brightness as well as the look of the edges.
Regards. KEN.

prometheus
10-31-2014, 12:37 PM
Thanks for your comments and advice.
As a result I can now change the lighting to get the effect im after.
The issue was this.
When you turn on the headlight and you have some upright oblongs and squares in the scene.
The edges of theses objects can be washed out by the headlight.
Also the headlight can appear very bright.
There are no controls associated with the headlight to change anything.
Hence my question here about an equivalent lighting set up.
Having tried out a few things ive found that simply changing the default light to an area light
and changing the ambient intensity to about 60% improves the edge aspect and the ambient control
allows you to control the brightness as well as the look of the edges.
Regards. KEN.



well...sensei´s plugin might be for you...however, working with ambient light at such level as 60% is probably way wrong to go...in fact, most people never use it in renders nowadays when you got radiosity and dome lights...ambient light sort
of gives a flat appearence without any depth in it, so most people probably turn it of to zero, why have it then..well it helps outline objects in the scene for a starter, until you have set up your "Real" lights properly.

upprigth oblongs and squares? do you mean shadows? you can turn off shadows for any light you want, or exclude any object in the lights object list.

Sensei
10-31-2014, 02:27 PM
ambient light sort
of gives a flat appearence without any depth in it, so most people probably turn it of to zero, why have it then..

Flatness of ambient light. That's why Headlight plugin is using Area light type.

Ambient light is simply:
color = ambient color * intensity;

While any light type will have:
color = light_color * max( -dot( light_normal_vector, surface_normal_vector), 0 ) * intensity;

(in multi-sample light type like area light_normal_vector is randomly perturbed)