I've been working hard getting all the rendering features to work together in one unified system. Ultra Engine, more than any renderer I have worked on, takes a lot of different features and integrates them into one physically-based graphics system. A lot of this is due to the excellent PBR materials system that Khronos glTF provides, and then there are my own features that are worked into this, like combined screen-space and voxel ray traced reflections.
Anyways, it's a lot of di
Midjourney is an AI art generator you can interact with on Discord to make content for your game engine. To use it, first join the Discord channel and enter one of the "newbie" rooms. To generate a new image, just type "/imagine" followed by the keywords you want to use. The more descriptive you are, the better. After a few moments four different images will be shown. You can upsample or create new variations of any of the images the algorithm creates.
And then the magic begins:
I wanted to take some time to investigate geospatial features and see if it was possible to use GIS systems with Ultra Engine. My investigations were a success and resulted in some beautiful lunar landscapes in a relatively short period of time in the new game engine.
I have plans for this, but nothing I can say anything specific about right now, so now I am working on the editor again.
Leadwerks had a very well-defined workflow, which made it simple to use but also somewhat limi
This is an update on my progress of our voxel raytracing system. VXRT is designed to provide all the reflection information that PBR materials use. If a picture is worth a thousand words, then this counts as a 5000 word article.
Direct lighting:
Global illumination:
Specular reflection:
Skybox component:
Final combined image:
I've actually been doing a lot of work to finalize the terrain system, but I got into tessellation, and another rabbit hole opened up. I've been thinking about detailed models in VR. Tessellation is a nice way to easily increase model detail. It does two things:
Curved surfaces get smoother (using point-normal triangles or quads)
A displacement map can be used to make small geometric detail to a surface.
These are really nice features because they don't require a lot of mem
I have more than one light bounce working now, and it looks a lot nicer than single-bounce GI. The ambient light here is pure black. All light is coming off from the direct light, and bouncing off surfaces.
It will take some time to get the details worked out, and more bounces will require more memory. I'm actually kind of shocked how good looking it is. This is just a single 128x128x128 volume texture at 0.25 meters per voxel. Light leaks seem to be not a problem, even at that low re
At long last, the engine that felt like it would never be done is here. This is all the result of an idea I had and wanted to put to the test. Of course I never anticipated it was possible to deliver a 10x improvement in rendering performance, but here we are with the benchmarks to prove it.
Research & Development
The last four years of research and development were an opportunity to rethink and redesign what a game engine should be. Along the way there were a few ideas I had that
Ultra Engine makes much better use of class encapsulation with strict public / private / protected members. This makes it so you can only access parts of the API you are meant to use, and prevents confusion about what is and isn't supported. I've also moved all internal engine commands into separate namespaces so you don't have to worry about what a RenderMesh or PhysicsNode does. These classes won't appear in the intellisense suggestions unless you were to add "using namespace UltraRender" to y
Before proceeding with multiple GI volumes, I decided to focus on just getting the lighting to look as close to perfect as possible, with a single stage.
Injecting the ambient light into the voxel data made flat-lit areas appear much more "3D", with color bleeding and subtle contours everywhere.
Lighting only:
Lighting + albedo
Some adjustments to the way the sky color is sampled gave a more lifelike appearance to outdoor lighting.
Before:
After. N
I'm wrapping up the terrain features now for the initial release. Here's a summary of terrain in Ultra Engine.
Terrains are an entity, just like anything else, and can be positioned, rotated, or scaled. Non-square terrains are supported, so you can create something with a 1024x512 or whatever resolution. (Power-of-two sizes are required.)
Editing Terrain
Ultra Engine includes an API that lets you modify terrain in real-time. I took something very complicated and distilled it down
I haven't been blogging much because I am making so much progress that there would be too much to cover. In this article I will talk about one little system I spent the last week on and show the improvements I have made to the workflow over Leadwerks.
In the asset editor, when the root of a model is selected, a "Collider" field appears in the physics properties. You can use this to quickly calculate and apply a collider to the model.
The convex hull collider includes an option fo
Many games store 3D models, textures, and other game files in some type of compressed package format. These can be anything from a simple ZIP file to a custom multi-file archive system. This has the benefit of making the install size of the game smaller, and can prevent users from accessing the raw files. Often times undocumented proprietary file formats are used to optimize loading time, although with DDS and glTF this is not such a problem anymore.
Leadwerks uses built-in support for encr
I recently fired up an install of Ubuntu 20.04 to see what the state of development on Linux is now, and it looks like things have improved dramatically since I first started working with Linux in 2013. Visual Studio Code looks and works great on Linux, and I was able to load the Ultra Engine source code and start compiling, although there is still much work to do. The debugger is fantastic, especially after using the Code::Blocks debugger on Linux, which was absolutely sadistic. (They're both u
Until now, all my experiments with voxel cone step tracing placed the center of the GI data at the world origin (0,0,0). In reality, we want the GI volume to follow the camera around so we can see the effect everywhere, with more detail up close. I feel my productivity has not been very good lately, but I am not being too hard on myself because this is very difficult stuff. The double-blind nature of it (rendering the voxel data and then using that data to render an effect) makes development ver
Package plugins are now supported in Ultra Engine 1.0.2. This allows the engine to handle other package formats besides just ZIP. In order to test this out, I created the Quake Loader plugin, which currently supports the following formats used in the original Quake game:
PAK
WAD
BSP (textures)
SPR
LMP
Why Quake? Well, the original Quake game is what got me into game development through modding, but Quake is also great for testing because it's so weird.
Previously I described how I was able to save the voxel data into a sparse octree and correctly lookup the right voxel in a shader. This shot shows that each triangle is being rasterized separately, i.e. the triangle bounding box is being correctly trimmed to avoid a lot of overlapping voxels:
Calculating direct lighting using the sparse octree was very difficult, and took me several days of debugging. I'm not 100% sure what the problem was, other than it seems GLSL code is not quite
A new update is available for beta testers. This update focuses on the GUI capabilities, mostly for interfaces created directly on a window, rather than 3D interfaces. We are moving from a Lua-driven GUI system to one coded more explicitly in C++. This will provide us with better documented behavior, easier portability, and a more responsive interface.
Changes:
GUI widgets no longer use Lua scripts. Each widget type has a C++ class, a creation command, and style constants.
A
The glTF importer took a very long time to develop, but it much easier to write a glTF save routine. In one day I got an exporter working with support for everything except skinning and animation. To save a model in glTF format, just call Model::Save("mymodel.gltf") and it will work! Entire scenes can also be saved in glTF format.Here is a model that was loaded from Leadwerks MDL, MAT, and TEX files and saved as glTF. The textures are converted to PNG files. (Microsoft has an official extension
The Ultra Engine editor is designed to be expandable and modifiable. Lua script is integrated into the editor and can be used to write editor extensions and even modify the scene or the editor itself in real-time.
We can create a scene object entirely in code and make it appear in the scene browser tree:
box = CreateBox(editor.world)
box.name = "box01"
o = CreateSceneObject(box) --make editor recognize the entity and add it to the scene browser
o:SetSelected(true)
We can even
The VK_KHR_dynamic_rendering extension has made its way into Vulkan 1.2.203 and I have implemented this in Ultra Engine. What does it do?
Instead of creating renderpass objects ahead of time, dynamic rendering allows you to just specify the settings you need as your are performing filling in command buffers with rendering instructions. From the Khronos working group:
In my experience, post-processing effects is where this hurt the most. The engine has a user-defined stack of post-pro
I'm finalizing the shaders, and I was able to pack a lot of extra data into a single entity 4x4 matrix:
Orthogonal 4x4 matrix
RGBA color
Per-entity texture mapping offset (U/V), scale (U/V), and rotation
Bitwise entity flags for various settings
Linear and rotational velocity (for motion blur)
Skeleton ID
All of that info can be fit into just 64 bytes. The shaders now use a lot of snazzy new function like this:
void ExtractEntityInfo(in uint
Heat haze is a difficult problem. A particle emitter is created with a transparent material, and each particle warps the background a bit. The combined effect of lots of particles gives the whole background a nice shimmering wavy appearance. The problem is that when two particles overlap one another they don't blend together, because the last particle drawn is using the background of the solid world for the refracted image. This can result in a "popping" effect when particles disappear, as well
When it comes to complex projects I like to focus on whatever area of technology causes me the most uncertainty or worry. Start with the big problems, solve those, and as you continue development the work gets easier and easier. I decided at this stage I really wanted to see how well Vulkan graphics work on Mac computers.
Vulkan doesn't run natively on Mac, but gets run through a translation library called MoltenVK. How well does MoltenVK actually work? There was only one way to find out...
Google Draco is a library that aims to do for mesh data what MP3 and OGG did for music. It does not reduce memory usage once a mesh is loaded, but it could reduce file sizes and improve download times. Although mesh data does not tend to use much disk space, I am always interested in optimization. Furthermore, some of the NASA models I work with are very high-poly, and do take up significant disk space. Google offers a very compelling chart showing a compression ratio of about 95%:
Ho
As I have explained before, I plan for Ultra Engine to use glTF for our main 3D model file format, so that your final game models can be easily loaded back into a modeling program for editing whenever you need. glTF supports a lot of useful features and is widely supported, but there are a few missing pieces of information I need to add into it. Fortunately, this JSON-based file format has a mechanism for extensions that add new features and data to the format. In this article I will describe th
