If love it, make it free (c) ;)
Trying to steal Vray's thunder.
Rudy Lamotte gave some solid tips on approaching vegetation production for video games and shared various techniques you can use.
Hello everyone! I’m Rudy Lamotte, and I’m a Vegetation Artist currently working at Ubisoft in Annecy, France. Before my current job, I worked at Kylotonn in Paris on some awesome racing games, like WRC6 and Flatout, where I honed my skills within SpeedTree. During my spare time, I strive to improve my skills in order to create pieces of art with the utmost quality, meaning I find new methods of approaching the creative process to be quicker, smarter, and more efficient in my work. At the end of the day, I’m a self-taught artist who is absolutely passionate about video games and in-game environments!
When I start an environment, my inspiration mostly stems from seeing a wonderful reference picture or some recently triggered mental image. Video games inspire me as well!
The first main task for the production process is to gather references of the environment that is to be produced, to do some Moodboard, and to establish a list of meshes that will have to be produced. Then, when everything is ready, it’s all about blocking out the scene.
First things first, I acquire nice references of the vegetation that is to be produced in the environment. After this initial step, I then begin working within SpeedTree to make the trunk, branches, and leaves. One important thing to note is keeping a homogeneous shape at the top of the tree for the imposter. If this step is overlooked, any huge asymmetric shape with holes in it will easily be noticed from far away.
Variation is important as well! I tend to make two or three variations per type of tree depending on its density and visibility.
Below is a simple nodal for a tree. Nodals can be much more complicated, but let’s use this one as an easy-to-follow example!
It’s always important during the leaf creation phase to make several specific meshes that fit textures previously created in SpeedTree. Also, avoid having too many leaf cards on your tree—it’s always better to have fewer cards! Further, when creating leaf cards try to have as little empty space as possible because overdraw ultimately costs a lot.
The texture part in SpeedTree lets artists make a significant variety of branches that results in a texture Atlas. Afterwards, one has to export to material each branch that is being made. Yet, there are other ways to accomplish this, such as making a high poly model and/or a sculpted one and then baking the model down to textures.
Afterwards, set up the Ambient Occlusion and your Normal Map of the tree.
Lastly, at the end of the production process, optimize the tree depending on the kind of game in which it will appear and the budget of the game (here’s to hoping you have a budget that permits optimization!). Generally, I make three LODs (level of distance) and the imposter.
Here’s another really important thing to keep in mind! Be sure to create a small area in the game’s engine to test how the vegetation looks and how everything works together.
Below is an example of some vegetation working well together.
There’s nothing fancy about grass. Mainly, keep it simple, make the mesh as low as possible, and ensure there are no glaring oddities within the grass. Avoid having parallel planes and move the planes around to guarantee a circular shape. Also, don’t hesitate to bring different sizes into the meshes.
Ultimately, the texture part is up to the artist. Either the artist models the blade in a longer fashion, obtains a nice grass texture from Megascans (or somewhere else), or captures images of blades of grass with his or her own DSLR camera. Then, once in Unreal Engine, the artist wants to blend the grass with the ground to make it look more interesting as demonstrated in the example below.
Here’s the material for the blending.
I mainly used World Machine for generating the heightmap or the mesh for the background mountain. Sometimes, I enjoy sculpting terrain in ZBrush and bringing it to World Machine for greater detail. However, when the terrain is covered with plenty of vegetation there is no need for World Machine as one can quickly just sculpt the main shape.
Below is an example of my work from World Machine.
Later on, it’s also good to have multiple outputs to make sure the texture of the terrain looks great. By having multiple outlets, one also increases the amount of control he or she has over the texture.
Using Ready-made Vegetation Libraries
Well, I will say that if one starts with vegetation it’s best to look at the SpeedTree library to learn how they are making their trees. It’s also readily accessible to the masses—aspiring vegetation and environmental artists can find basic tutorials on YouTube!
Megascans is a rich source of materials; however, I honestly prefer going outside with my camera and shooting what I need because it’s more gratifying than relying on Megascans. I completely understand utilizing Megascans if an artist doesn’t own or have access to a camera, but I also believe it’s important to think outside the box and be creative with one’s surroundings. For instance, let’s say you want to include a large stone wall in your game but there’s not a large stone wall anywhere near your home. What do you do? Rather than turning straight to Megascans, I think it would be great if an artist took pictures of some rocks and creatively turned those images into the desired large stone wall.
Over the years, I’ve amassed many references and now have my own library of trees that allows me to quickly produce vegetation. With this library, I don’t begin from scratch every time I approach a new project. Rather, I can easily choose a tree that looks similar to my desired end product and simply reshape it to meet that new look, which saves me time and energy.
Light and Effects
My setup for environments is straightforward. For the lighting, I have a directional light and a skylight. Moreover, I use DFAO with the rest of the lighting being a matter of tweaking the intensity values of the light.
I also use Post Process Volume, Exponential Height Fog, and an Atmospheric Fog that really help to embellish the scene with a realistic look.
Below is another environment where fog is used to create depth.
Photogrammetry is becoming really popular with artists today and many studios have already implemented it into their workflows because it’s a really great method to achieve realistic graphics in a quick fashion! And when an artist can’t access a specific subject or its textures, that artist then can combine photogrammetry and other techniques to achieve a desired result.
I won’t get into specific details about photogrammetry, since I’m still learning it myself, but the basics include the following.
- A DSLR camera is ideal! Try equipping yourself (within budget) with the best full-frame camera possible that also has a high memory capacity.
- A wide angle lens that allows more light in and also captures a larger area with each picture.
- Don’t go outside when the weather is sunny or it’s raining. Overcast weather is the best weather for photogrammetry!
- Don’t overexpose or underexpose your picture.
- Pictures should contain as little lighting information (shadows and highlights) as possible so that the artist can post process any image in Photoshop to clear some of the lighting.
- Take one picture with an X-Rite ColorChecker Passport.
- Make sure to use the same focal length for pictures, and avoid using autofocus features on DSLR cameras.
- Take plenty of pictures—the more pictures one takes, the more references one has. This is quite the time consuming process, so I hope patience is a virtue among 80.lv readers! Lastly, be sure to capture every possible angle of an object to ensure a comprehensive take on how to model it in 3D.
- Find a software to process pictures, such as Agisoft Photoscan or Reality Capture.
Below are two examples of trunks scanned in these kinds of software.
Scanned in Agisoft
Rendered in Marmoset
I hope this was an enjoyable, informational, and inspirational read for you! Thanks for taking the time to read about my work—feel free to check other projects of mine on ArtStation!