Thursday, March 29, 2012

Real-time path traced Babylonian city with mesh light + spaceship test

Some WIPs with Brigade 2:

The first scene demonstrates a moving mesh light flying over the city scene from the previous post. Mesh lights are a notorious source of noise in path tracing, but Brigade handles them pretty nicely (all videos and screenshots rendered with 2 GTX 580 GPUs) :

The following WIP shows an extremely detailed spaceship (free model from TurboSquid):

850k triangles rendered at 10-30 fps and 1280x720p render resolution: (be sure to watch this at 720p)

UPDATE: video with sun


Purely reflective:


These tests undeniably show that real-time high-res path tracing of highly detailed and complex scenes is possible today using just one or two GPUs. This is a major breakthrough and very hard to believe, most people were thinking this would be at least 10 years away. To be honest, I have a hard time believing it as well. I'm constantly OMGWTF when loading up a new model and seeing it in all its path traced glory :-)

Stay tuned for my next blogpost, in which I will show a highly detailed modern city.

Monday, March 26, 2012

Real-time path tracing: Babylonian city test

Another outdoor test with Brigade 2 of a massive city model ("Babylonian City", a SketchUp model by LordGood).

Real-time video, rendered at 1280x720 resolution on 2 GTX 580s at ~10 fps: (watch in 720p)

UPDATE: 30 fps video with "variable" blur

UPDATE 2: At the request of my Aussie mate Radiant, I've uploaded a real-time video in 1080p Full HD (1920x1080):

- 500k triangle scene
- lit by sky + sun
- 30 fps at 640x480, 10 fps at 1280x720 on 2 GPUs (faster without sun)
- brute force path tracing with max path depth 8 (maximum 7 diffuse light bounces, which is rarely attained, because most rays "escape" to the sky)

Sun disabled:

Textures disabled:

True cinema-quality lighting in real-time :-). More outdoor scenes soon.

Friday, March 23, 2012

Brigade color bleeding test 2: bloody town

Small color bleeding test with Brigade 2. The scene (SketchUp city scene by LordGood) is untextured to better show the diffuse color bleeding:

Real-time video (30 fps on 2x GTX 580):

In the next image, there are a bunch of interesting light effects happening on the houses on the left, such as bright sunlight reflecting from the pentices:

I wanted to create an outdoor scene with the same quality of lighting as Mirror's Edge (which uses very high quality, baked lightmaps and which I think is the most photorealistic looking game of this generation, see for example this pic and this one), but in real-time.

Tuesday, March 20, 2012

Real-time path tracing: Bunny, Dragon and Teapots Medieval meeting

I've added a few classic 3D objects to the scene from the previous post, the Stanford Dragon and the Utah teapot. The following screens and video show off the materials that are currently supported the Brigade path tracer and were rendered in real-time on 2 GTX 580 GPUs:



The realism you can achieve with this tech in real-time is utterly insane. These are some of the features you won't find in any real-time game engine: 

- global illumination with 100% accurate diffuse interreflections

- raytraced reflections and refractions on arbitrary shaped surfaces

- physically based glossy reflections

- caustics (under the glass dragon)

- perfect raytraced soft shadows, that don't eat any GPU memory 

- raytraced ambient occlusion (e.g. the darker spots under the teapots)

- combinations of multiple reflections, refractions, soft shadows and diffuse GI (e.g. a reflection of a shadow of a glass object) are automatically and robustly rendered without any artist intervention 

I will be using this scene for a simple game, probably a survival horror or a puzzle/adventure game. 

WIP update: just an idea for my survival horror game: this jolly character will chase the player through the streets:

Friday, March 16, 2012

Real-time path traced Stanford Bunny in ancient city WIP 1

Working on a new real-time path traced game scene (400k triangles) set in an ancient city and rendered with the Brigade path tracer. The scene is a freely available SketchUp scene created by LordGood. The bunny model is a 5k triangle version of the Stanford Bunny and is dynamic.

First WIP screens and video:

Youtube vid:

- 400k triangle scene
- dynamic objects, receiving the exact same lighting as the game world
- real-time rendered lighting, fully dynamic
- sun/sky light
- artifact free soft shadows, which consume no memory at all
- real-time diffuse global illumination (path traced)
- GPU path tracing on 2 GTX 580 GPUs 

Brigade essentially renders light map baking for games obsolete, including radiosity and VPL/LPV based GI methods. More videos with a greater diversity of materials (diffuse, refractive, glossy, reflective) will follow soon.

Thursday, March 15, 2012

Sunny real-time path traced Sponza!

Another real-time Brigade test with the sun on Sponza, a more challenging scene with lots of areas with indirect lighting.

Video (32 spp per frame):

The toad was modeled by Son Kim. The video is pretty dark in some areas, so to see all the details, I advise to watch it without too much environment light.

This scene is the gold standard to test how well a newly developed GI algorithm handles indirect lighting scenarios. With Brigade it is possible to render this scene at photorealistic quality in real-time on just two GTX580 GPUs (one Kepler GPU should easily surpass surpass this). 

Beautiful diffuse colour bleeding on the toad:

I've decided to work on a real game-like outdoor city scene, something like the open world city in Assassin's Creed, but with photoreal quality real-time path traced global illumination. I'm currently working on an ancient city scene (400k triangles, model from SketchUp). Expect a video with this model soon, showing dynamic sunlight and real-time updated GI (it renders effortlessly at 10-20 fps).