paulselhi
1-11-04, 11:42 AM
If you have ever spent hours trying to get realistic lighting and shadows in 3d renders you may well have heard of radiosity, then again you may have not
For those who have not, radiosity is the bouncing of light from one object onto another. Much like the light in a room effects objects directly in it's path but that light is also bounced from object to object.
Thus light from say a window will have an effect of objects that are behind other objects due to the former radiating light to the later as well as light bouncing of other objects e.g. the walls
Trying to setup a scene with multiple lights to get a realistic effect is a headache and most good 3d progs have a radiosity option which though time consuming in rendering is well worth investigating
here are some examples :
in this render there is a simple omni light at the end of the room
plain light (http://www.black-and-white-to-color.com/stuff/lightinnorad.jpg)
pretty boring !!
Ok here it is with raduiosity on
radiosity (http://www.black-and-white-to-color.com/stuff/lightinrad.jpg)
Much better, note the subtle shading at the corners
though radiosity takes some time to render it can be "baked" and then the reultant imnage is used as a texture map, this means that assuming no objects in the scene are moving then you can render an animation with a camera moving through the scene that has radiosity applied and the render times are amazingly short
Now have alook at this
streaming light (http://www.black-and-white-to-color.com/stuff/lightoutnorad.jpg)
interesting but very dull
Now with radiosity
streaming light rad (http://www.black-and-white-to-color.com/stuff/lightoutrad.jpg)
ah much better
I have to go and watch a spccer match now but i will give some more examples later as well as some better explnantions
For those who have not, radiosity is the bouncing of light from one object onto another. Much like the light in a room effects objects directly in it's path but that light is also bounced from object to object.
Thus light from say a window will have an effect of objects that are behind other objects due to the former radiating light to the later as well as light bouncing of other objects e.g. the walls
Trying to setup a scene with multiple lights to get a realistic effect is a headache and most good 3d progs have a radiosity option which though time consuming in rendering is well worth investigating
here are some examples :
in this render there is a simple omni light at the end of the room
plain light (http://www.black-and-white-to-color.com/stuff/lightinnorad.jpg)
pretty boring !!
Ok here it is with raduiosity on
radiosity (http://www.black-and-white-to-color.com/stuff/lightinrad.jpg)
Much better, note the subtle shading at the corners
though radiosity takes some time to render it can be "baked" and then the reultant imnage is used as a texture map, this means that assuming no objects in the scene are moving then you can render an animation with a camera moving through the scene that has radiosity applied and the render times are amazingly short
Now have alook at this
streaming light (http://www.black-and-white-to-color.com/stuff/lightoutnorad.jpg)
interesting but very dull
Now with radiosity
streaming light rad (http://www.black-and-white-to-color.com/stuff/lightoutrad.jpg)
ah much better
I have to go and watch a spccer match now but i will give some more examples later as well as some better explnantions