Recently we had to create a gas fireplace in a living room for a German Company, in around 10 minutes. Time was very short so we had to think of a fast and efficient way to do it without much worries. First thing we did was to create a plane and subdivide it enough to have a nice noise modifier in it. Very simple just take a look at the screenshoot below. Since we were working in a small scale project, the units that we used were millimetres.
Now, with the plane ready we developed some pebbles with the free Rock Generator plugin which you can find here. This plugin is able to create much more complex stones than what we just did, but for this job we just went for something simple, which we could also do with basic spheres. Anyway here´s the result, some pebbles that we converted to vray proxy:
Once we had the pebbles set up we distributed the correspondent vray proxy models in the previous noise plane using Multiscatter plugin. You can also do it using the free Advanced Painter plugin. Anyway here are the settings used to distribute the small rocks. Notice that we ticked receive collisions (60% radius) so that the pebbles don´t mess with each other. Also random rotation (360) and some scale differences were used in order to have a more random distribution effect.
After the pebbles are placed,we created a fire material inside another plane with noise.
Textures were download from CGtextures.com as usual and later on modified in photoshop. Here are the maps used (just right click and save as). The material itself is a diffuse and an alpha map inside a VrayLight Material.
Now comes the part where we animate the noise of the plane with fire. First set up the noise in the plane as seen in the frame zero below. Afterwards press AutoKey (bottom right of the screen) and select frame 2. Soon after (at this time you must see a red bar in the frames) change the values of the noise till you reach something like a wave plane.
The objective now is to turn on motion blur in the camera (subdivisions around 8 and 10 is enough) and set the rendering time to frame 1 or 2. In our opinion, since fire in reality has blur effects, we believe that giving blur to the map and to the camera makes the fire effect look more realistic. All this in a fast way. Please take into consideration that this work was done for a still image job, and not for an animation.
Hope you have enjoyed reading and that this tutorial is somehow useful for you.