What Makes UE4 Tree Models Special?

Need trees in your UE4 project? We’ve got a diverse and growing library of trees and plants for UE4 subscribers in our SpeedTree for UE4 Model Library . . . from conifers and broadleaves to flowers and bushes. And if you don’t find the right tree, try out our SpeedTree for UE4 Modeler for $19 for a month, which lets you create new species from scratch or just tweak what’s in our library.

But you don’t need the SpeedTree Modeler to bring our trees into your project. Take a look at what’s packed into each model as soon as you buy it:

UE4 Drop-In Ready

Starting with Unreal Engine 4.3, our models will import directly into the engine and render with a default set of directly editable materials chosen by our artists.

Preset Lightmap UVs

Ever tried to create a lightmap for a tree model? It takes a lot of time to do well. Every one of our models comes with supremely well-organized lightmap UV coordinates with all LOD levels contained in a single map, and all models are tuned specifically to work with UE4’s Lightmass system. Just drop it in the engine, build the lighting, and you’re good to go.

Fully Editable With Modeler Subscription

Every model in the set comes in both SRT (SpeedTree Run-time) and SPM (SpeedTree Procedural Model) file formats. SRTs are compiled from SPMs and drop directly into the Unreal Engine. SPMs are editable within the SpeedTree Modeler. Even if you like to create your trees from scratch in the Modeler, starting with a fully-realized model can speed things along a great deal.

If nothing else, the Modeler can be used to create a new random variation of each tree with a single click.

Three Resolutions

Every tree model in the set is available in multiple resolutions:

  • Hero: A high detail tree that runs well in real-time. These are perfect when there are only a few trees in the scene or if a tree is particularly important (e.g. a big tree at the center of a town). Triangle counts normally exceed 15,000.
  • Mobile: Right around 1,000 triangles, these are great trees for targeting lower-performance platforms or just to use as distant fillers when billboards won’t do.
  • Desktop: This is the most commonly used resolution, hitting right in that sweet spot between Hero and Mobile trees. Commonly around 8,000 triangles, this is the default resolution when designing a title for use on PC/Mac, PlayStation® or Xbox®.

Seasonal Variations

Many of the models feature seasonal variations. Deciduous trees all have autumn and winter versions. Others may have snowy variations. Each seasonal variation is modeled in three resolutions: hero, desktop, and mobile.

Artist-Tuned LOD

The SpeedTree UE4 integration supports seamless LOD transitions. A typical desktop model might have three discrete LOD levels with triangle counts of 8,000, 4,500, and 1,800, and finally a normal-mapped billboard for very distant rendering. Our artists painstakingly tune the 3D LODs and the transitions in between to keep transitioning artifacts at a minimum.

Artist-Tuned Wind Effects

SpeedTree employs a very scalable wind effects system, supporting anything from simple global wind all the way up to cinematic-level as used in The Lone Ranger and many other feature films. Our UE4 models have been artist-tuned specifically for use with the SpeedTree/UE4 integration. Once imported, users can adjust the speed/complexity trade off by editing the Wind Type (e.g. fastest, highest-quality, etc), per material.

Branch Seam Reduction

In low-polygon modeling, a tree’s trunk and its branches are often modeled as cylinders shoved against other cylidners. Our models take full advantage of SpeedTree’s branch seam reduction feature as integrated into UE4. Without using sub-division surface modeling or unwrapping the branch/trunk texture, a smooth seam is still possible where the branches meet the trunk. Because the texture still wraps, a higher overall texture resolution appearance results.

Preset Ambient Occlusion

Per-vertex ambient occlusion is included in every tree model, tuned by our artists to darken the interior or otherwise obstructed parts of the tree model. When dynamic shadows aren’t possible, SpeedTree’s ambient occlusion can make a huge difference in rendering quality, especially for the lower-polygon models. The image at right shows a desktop tree model with no dynamic or static shadows and then that same tree with our ambient occlusion applied.

Preset Collision Objects

All tree models will have medium-detail collision objects already placed and ready to work with UE4.

Helper SPM Models

For tree models where it’s impractical to model every leaf separately, creating convincing leaf clusters is important (example at right). Many of our models include SPM files to help generate these automatically. Using the Modeler, users can easily tweak the individual leaf sizes, quantities, and color variations. The Modeler will also automatically generate the diffuse, normal, specular and transmission masks – all without ever opening Photoshop®.

Quality Textures

We supply high-resolution textures with all of our models, often higher than is commonly used in real-time, allowing you to scale down to the resolution you need. Models include diffuse and normal maps with alpha masks. Masked textures also include edge padding to prevent bleeding at lower mip levels.

Ever-Growing Library

Because we’ve packed in so many features into each of the UE4-specific model sets on our store, we’ve been slow to build up a very large library. Rest assured that we’ll be adding new models every week – check back often!