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Country Lane, Derbyshire, UK

Now on SteamVR:

https://steamcommunity.yuanyoumao.com/sharedfiles/filedetails/?id=951612838

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140 photos, taken in early January 2016. Processed using Reality Capture for foreground geometry and Agisoft PhotoScan for distant geometry and the skydome.

Built partly to test workflows and quality of source data prior to returning to the UK for Christmas, I thought I'd document some of my latest findings and further detail the processes involved.

The overall scene was pretty much built in the manner already documented here: https://developer.valvesoftware.com/wiki/Destinations/Advanced_Outdoors_Photogrammetry

The road surfaces were very damp from heavy rain the previous night - so due to the specularity baked into the source photos, the road textures had horrible blotchiness and discontinuities in brightness. I first separated the road surfaces out into a separate mesh and made some nice, sane UVs for them (planar projection from above, chopped into pieces so as to better utilise the UV space). Then in PhotoScan I built two new sets of textures for the scene - one using 'Mosaic' and the other 'Max Intensity'. The former was blended a bit better than Reality Capture's attempt (the software strives to preserve fantastic detail, but can admit defeat with poorer source images), while the latter Max Intensity texture ended up being an interestingly smooth, 'specular only' texture.

In Photoshop, I composited them together - a levels-tweaked Max Intensity layer overlaid on the Mosaic layer (luminosity blending at 50%), then with a high-passed Mosaic layer over those (overlay blending) in order to bring back some of the lost detail. Subsequent tweaking in Photoshop involved cloning to patch up the remaining discontinuities, then copying the ends of road UV islands to match up adjoining sections.

A further Reality Capture / PhotoScan hack involved separating out the grass verges close to the road into another mesh; I also generated textures for these in PhotoScan, and blended them over the Reality Capture versions as appropriate. (PhotoScan's averaging can potentially look better on super-complex surfaces projected on to simpler geometry - the results are a bit smoother than Reality Capture's detail-preserving version).

Cars were made by building rough bodies for them to fill out the dodgy, broken-by-specular skeletons left after reconstruction. They look pretty bad up-close, but fine from a distance - I need to investigate scanning such things a bit more.

Smoke from chimneys is from a simple particle system built using this tutorial as a basis: https://developer.valvesoftware.com/wiki/Dota_2_Workshop_Tools/Particles/Particle_Effect_Tutorial_1 - it turns out we have some nice smoke sprites in Destinations already, so I didn't need to make new ones.

Known flaws in source material: no photos looking at downslope of grassy bank (I need to make sure I capture such features better in future), and no photos above and beyond the hedges and walls (there's a garden that you can see the reconstruction break down on). Also, shoot at a lower ISO (the challenging light had me mess up exposure a bit, which was rescued in Lightroom) and generally take more photos anyway. More source material is always welcome!


Again, if you have any questions about this scene, or scene photogrammetry for VR in general, please don't hesitate to ask!