
The logs and grate were free models downloaded from 3D Warehouse with a bit of modification to remove sharp edges, put in my own materials etc.
https://3dwarehouse.sketchup.com/model. ... b05b21288d
Flames * EDIT * - PLEASE READ POSTS BELOW FOR A BETTER METHOD USING EMITTING NULL
I found an image of some flames on Google and then made corresponding clip and bump maps. I made an emitting material using the flames as a light source and then blended that with a null with the fire only at 5% visibility. I found this gave a good mix of light emitted whilst allow you the see through the flames a little. This material was applied to 4 planes throughout the logs as shown below.
Smoke
The smoke is just a .png image of smoke with a diffuse material, and again blended with a null this time with the smoke at 15% visibility. This material was applied to a simple plane in the middle of the logs.
Ashes
The ashes are a mix of 3 elements 1. some little pebbles 2. a displaced shape to look like a heap of small pebbles and 3. a displaced shape with the 'Fire Embers' material from the Mat DB applied.
Tweaks to improve realism
As there are not (as yet

The last thing I did was to introduce a small amount of motion blur to the flames to give them that 'roaring up the chimney' look, this was done using Key Frames. I set the default position of the 4 flame planes as 0, moved them up 20mm and set this second position as 1.
And that, as they say, is that! Hope this help some people!
