Here is a quick overview of a method I use to distribute still images over a network using C4D Net. While it's technically true that Net is not designed for stills, here is a common workaround, which I have tailored to the C4D toolset.
Let's assume for the sake of argument that you have a ridiculously large still image you need to output, something along the lines of 6400 by 4800 pixels. Let's also assume that you have a renderfarm of 8 clients. This number is arbitrary, you could have 80 clients for all I know. Just alter the math used in this tutorial to suit your unique situation.
Let's get to work. The first thing you need to do when you are ready to render is to add a Foreground Object (Objects>Scene>Foreground Object).
Now you have a foreground object in you Object manager.
Next we need to apply a Material to our Foreground Object. We will activate only the alpha channel on this material which will serve to poke holes in our foreground object which we can then animate to create slices which can be distributed over many machines. Below are the texture settings I use to create the basic alpha channel.
Notice I have used the bhodinut Gradient channel to give us a completely black color which makes for an alpha channel with no opacity. Here are the simple settings I use.
Now comes the fun part. Apply your material to the FG object. Select either the Texture or Texture Axis tool to get a view of the orientation of you texture tile. For now you will see a blue grid over the whole area of your render frame.
We need to scale this blue grid and then animate its offset. First we need to go into our project settings and set up our special frame rate. Even though we are generating a still image, we will have to go into the timeline as if we were animating.
Now we will select the slowest, worst frame rate possible. One frame per second! This is just to limit each client on our render farm to one frame apiece. Below are the project settings I would use if i was planning to use a renderfarm of 8 clients.
Now we are going to go into the timeline and apply a texture track to our Foreground object (Timeline>File>New Track>Special Effects>Texture). Assign a keyframe to each of our 8 frames in the timeline. You should have something like this.
Here's where we get into a little math. The key is to assign a value to the Y value of our texture tile that reflects the number of clients we intend to use. Then we need to animate the Y offset to also reflect this value. So in a perfect world our Y value on our 8 client rederfarm should be 100 divided by 8. However I like to allow for a little overlap when I composite in Photoshop later so I usually set up this value as 100/8 +1. See below:
Notice this value applies so far only to Frame 1 of our "animation." For the top frame we can leave the Y offset at 0. As the frames progress the offset will move at a percentage that matches the number of clients, in this case 12.5, which is 100 divided by 8. Refer to the image of the values for frame 2 below:
Notice how the blue grid on our window is squished in the y direction and as the offset increases in the Y value, the tile descends. The same applies to frame 3 and so on with the Y value (in our example) increasing by 12.5 each time.
Continue this process for the remaining frames until you reach the end. If you scrub through the frames you will see the texture tile move on down from top to bottom (provided the Texture or Texture Axis tool is still active). Well, we're almost there. We just need to adjust our render settings to output our slices which we will then reassemble in Photoshop. Below are the settings I would use, in this example.
Obviously, the resolution should be much larger since a still of 640X480 wouldn't require a network solution in all likelihood!
Now you just prepare your project as you would any Net render project. Fire up your C4D Net Server and Clients and go to dinner while the image sequence works itself out among the various clients.
Now just load your frames one on top of the other in Photoshop as in the example below. Fortunately we have a little bit of overlap on each layer so that there is no visible transition. Happy rendering!
