Making of… Golden Forest

Concept for this Terragen 2 Tutorial

Terragen 2 tutorial on how to create a great looking scene in the simplest way possible using various tricks to keep the complications to a minimum. This Terragen 2 tutorial will take you through all the steps from concept to postwork I took to create the following image:

Golden Forest created with Terragen 2 tutorial

Software used

  • Terragen 2
  • Adobe Photoshop CS
  • Depth of Field Pro

First Step: Planning

First off you need an initial idea of what sort of image you are aiming for. You don’t need to have all the specifics in mind as I find it is a fairly organic process but the more focused you are the easier it is to make the proper choices in terms of complexity. For this scene my goal was simple, I want a forest, I want some fog, and I want some powerful and dynamic light.

Second Step: Adjust Your View

Now that I’ve defined my objective I need to decide on a camera field of view and an image orientation. I love the 16:10 aspect ratio so I locked my aspect ratio in the render tab to 1.6.

Since this is a forest scene and I don’t want to have any perspective issues (such as the trees converging towards the center of the image, I changed my Horizontal Field of View in the Render Camera node to 50. This will ensure that across the entire image the trees will be vertical.

Third Step: Build Your Terrain

Next step is to create some ground for your forest to be on as the default flat terrain just isn’t very interesting. I added a single fractal terrain for my landscape. The first time saving trick is here. I don’t plan on letting the viewer see the actual ground at all in this image so ground details matter very little. All I wanted was to build some slight hills so that the trees are not on a flat plane. From the default fractal terrain that was created I changed two parameters. I lowered the feature scale from 5000 to 2000 and I changed the displacement from 2000 to 150. From here I moved the camera around until I found a spot that would work well for the image. I lowered the camera down to around five meters above the ground.

Fourth Step: Surfacing

This is the best step of all and will take you no time to go through it. Since I plan on covering the entire visible area with vegetation, surfacing for the ground was left in the capable hands of the default Base Colours node.

Fifth Step: Vegetation Part One

I usually start with the biggest trees, so in this case I loaded one of each of Walli’s pine trees (Pine01_1, Pine01_2, Pine01small) and adjusted the area center and the area length a and b. For my plan of powerful lighting I know that I am not going to need to see very far in the distance and I don’t want much depth in the image so I choose my size to be 200 x 200. This will have the effect of your populations calculating very quickly and being fairly efficient with memory usage as the instances won’t be very high. I then switch to top view to move the population to be in the most efficient position possible. I want my trees to be fairly close together, but with enough space so that lots of light can still get through, so I change my spacing to be two meters. I then copy these setting to the other tree populations.

The standard distribution will make all these trees appear two meters apart from each other across the entire population bounding area in a fairly regular pattern. This is not what I want, so I need to create a distribution system. I create a surface layer and give it a name. Then I add this surface layer as a density shader in each population.

In the surface layer I change the coverage to 0.5 and the fractal breakup to 1 so that the distribution pattern is based on the fractal breakup node attached to the surface layer.

In the fractal breakup node I changed the feature and lead in scales to 10 and the smallest scale to 5. I increased the colour contrast to 0.75 and the colour offset to -0.25. I changed the noise pattern to Ridged perlin and changed the noise stretch to 5 in the x direction.

I then tested the populations a few times just to see what the trees looked like in their current placement. Things looked pretty good, but I had a couple trees growing through my camera, which I did not want so I added a distance shader to the population surface layer to keep the populations away from the camera.

I wanted to keep the populations a few meters or so away from the camera so I set the near distance to 4 and the far distance to 8. I set the camera to the Render Camera. This gives the effect of having the area 0 – 4 meters from the camera to have no trees at all and the area from 4 – 8 meters to start fading the trees in with the area further than 8 meters to have full tree coverage.

Further population checking of the trees and everything looked great so I added another population of trees (Bonus_Tree03) and attached it with the other trees.

Sixth Step: Light

The goal was to create dramatic, powerful lighting coming through the trees in a sunrise fashion, so I changed the sun position to be coming straight at the camera and a little over 5 degrees in elevation.

A quick test render showed that because of the density of the trees everything was still very dark so I knew I was going to need to give the light something to bounce around in so I created a cumulous cloud layer.

I reduced the altitude of the cloud layer to 200 and changed the edge sharpness and density to 0.1.

I wanted the cloud/fog to be in pretty small clumps and billows so I adjusted the feature and lead-in scales to 1 and the smallest detail to 0.1 to make them fairly rough in texture. I wasn’t getting quite as much cover as I wanted so I also adjusted the coverage to 0.1.

Another quick test render showed that I was now getting more light but it lacked the impact I wanted so I then increased the camera exposure to 3.

Seventh Step: Vegetation Part Two

Now that my light is how I want it, I added four populations of grasses to cover the ground just in case anything was visible through the fog layer. I used the same 200 x 200 bounding area as the trees and set the object spacing of each grass layer to be 0.5. I did not use a density shader as I wanted the grass to be everywhere.

Eighth Step: Rendering

Now that I had the scene fully built I changed some rendering settings.

  • Increased the cloud/fog quality to 2
  • Increased atmosphere samples to 84
  • Changed the render size to 1600 x 1000
  • Changed Detail to 0.9
  • Changed AA to 7
  • Changed GI Relative Detail to 2
  • Changed GI Sample Quality to 4
  • Checked Supersample Prepass

Rendering took approximately 7 hours and then I saved the image as both a .bmp and .exr file.

Ninth Step: Postwork

I opened the .exr file in Adobe Photoshop CS, so the steps I show here may be slightly different in more recent versions. Most steps should have a very similar option in the latest version of Gimp. Below is a small version of the untouched render when I first opened it.

My first adjustment is to work with the Highlights of the image, so I cntrl-click on the RGB Channel. This selects all the highlights in the image. I then create a new curves adjustment layer. I adjust the curve slightly.

Second adjustment is to the shadow areas. I again cntrl-click on the RGB Channel, then I invert the selection, and then again create a new curves adjustment layer. I adjust the curve slightly.

My next step is to duplicate the background layer and set the new layer to Soft Light.

Finally, I added a slight radial depth of field blur using the Depth of Field Pro Plugin, though you can easily do the same thing by using the Lens blur filter.

Now simply save as whatever sort of final image type you like.

The finished product can be found here:

Hopefully this tutorial demonstrates how easy it can be to create a fantastic looking render. If you go through the steps and try your own make sure to post the results to the Planetside Forums

Any comments, suggestions or problems can be sent to:

Ryan Archer
r.archer@shaw.ca

archer-designs.com