Sharing: Textured light texture with cycles

Support Materials and Textures
1

Hi,
I Just want to share a solution that I found for using in a cycles scene where I needed to have a kind of vortex of light. I managed to make it with the simple use of a PNG image as a texture for a emitter shader. I achieved what I needed and it might be useful as a substitute of particles - I got the textured transparency and light emitter at the same time and I can even choose the color for it. In the example below it resembles a galaxy (no particles involved ;)) but it can be used with any other texture (dots, lines, a face, clouds, whatever) as long as it is a white based texture.

The scene and resulting image

cycles-emittertextured-example.jpg574×638 38.3 KB

And the node for the material:

cycles-emittertextured-nodes.jpg952×388 68.9 KB

As I told, it’s just a share of experience and a solution that I hope can be useful for anybody. It can be handy in a lot of applications.
Cheers,
LM

2

this looks interesting

but difficult to follow what is what and where !

can you upload a sample file with the different objects
that would allow to see the different nodes set up on different objects?

meawhile i’ll try to prepare a white image for something! LOL
is this a white alpha image ?
or can it be white on black blackground?

thanks

3

Hi, Ricky

Sorry, I though to be explicit enough :wink:

It’s simply a plane like any emitter mesh used for lighting in cycles but instead of being a flat color we can apply a texture making the emitter plane not a flat light.
I could only achieve this effect with white png and no background - I assume that a black background will not work because the alpha in image is what matters to make the transparency in the material output.

Here is the file: http://www.pasteall.org/blend/16002

Note that any color based or transparent png works in cycles material but not for this type of material that I showed.
LM

4

i was wondering about galaxie
so this is an emission plane but with an image texture applied

i remember another thread wheere we treid to shine emission through a textured plane
and it did not show the texture onto another objecct !

image is not white on black so it is not an alpha image?

how to do it ?
you just make a white image and add some bluish on it may be?
can it be done in paint may be?
or only in Gimp using may be an alpha layer ?

thanks for sample file

5

Here is another image with some tests I made. The emission is based in the image texture being brighter where there is 100% of white and dimmer in other areas below the 100% of white (with blur effects for example).


As you can see the applications are practically endless and can be very handy in some projects - no particles, no volume and no post-processing. I’m sure some other tweaks may work (between type of image and node setup) but for now I can only do it with white painting in a single layer (no background at all).
I use mainly photo-paint and paint.net (the last one works very well with PNG files).

6

I can see virtual cities switching on neon lights… Nice.
Thanks for sharing!

7

Exactly! or some “Tron” suits with UV unwrap… or a devilish tatoo than sinhes red fire… whatever :wink:

I got into this solution when trying to make a vortex/wormhole in a cycles scene.
The only thing that is really missing is a way of previewing the material node output with cycles, otherwise it’s a mad trial and error to get a decent material.