Following one man's task of building a virtual world from the comfort of his pajamas. Discusses Procedural Terrain, Vegetation and Architecture generation. Also OpenCL, Voxels and Computer Graphics in general.
Saturday, October 20, 2012
Fall colors
Here is a video showing the new skylight feature. Trees now can have different foliage. Adding fall colors was a nice way to test this. These trees share the same foliage texture, it is colorized on-the-fly by the shaders.
That's weird, I soon stopped looking at the shadows and the LOD transitions, I was simply walking around a nice place, looking at both the grass and the weird mountains.
No idea how all this will look at the end, but will be awesome. Even just as a "trekking" simulator!
This is just stunning. At 2:40 when you can see the far hillside, that view just left me speechless. Really beautiful work!
Couple of points about the sound:
a) footsteps are way too loud and consistent. There's also something wrong with the spacing of the sounds vs the speed of movement. b) bird songs need to be 'located' somehow, so if you're walking around they get louder and softer according to distance. That may not be possible or viable, of course. :)
Yes, popping is evident because it happens too close to the viewer. A simple solution is to push LOD switches further from the view, but this also means you must buffer a lot more and this may not be possible all the time.
Now, you would also notice foliage changes are far more noticeable than the terrain. This is due to the billboard resolution changing from one LOD to the next. I would like to have a consistent resolution across all LOD, but this would hurt the framerate.
Perhaps for the popping issue, could you make it so that it staggers the popping? It could be a quick and dirty way to get more milage out of your current method. I think the most jarring is when a good portion of the screen changes all at once. If it were done on a more random basis, it could trigger one of those optical illusion things that our brain does to ignore missing details. ( I dodn't know the name, but refer http://www.ted.com/talks/dan_dennett_on_our_consciousness.html @ 17min)
Another thing to address it would be some type of mip-map merging transitons. If you were to change the texture and the model separately (especially with the leaf volumes on the trees) Once the texture is decoupled, it could be faded in more slowly for a less jarring transition like a cross-blur or simple alpha blend. Of course you would also need to use a range based system to avoid flickering, but I suspect you already are using that for the pop system.
lastly, with the tree leaves waving back and forth, your pop has both a geometry, and a movement disparity that is likely triggering our "uncanny valley" response.
The game "Black & White" used the texture transitioning effect, and it's terrain had an interesting tessellation method that meant for more fine-grained LOD. Similarly, it had some ability to warp polygons to shape as you got closer. That game was known for it's amazing LOD system at the time, so it could be something to emulate. http://www.youtube.com/watch?v=1BTAI8KXeH8&t=2m0s Especially interesting was how it layered in the detail texture on the terrain, that part always amazed me.
Basically, the biggest way to get rid of LOD issues is to treat it more similarly to how the human eye focuses on things. As you get closer, they transition to more detail gradually, or if they are suddenly transitioned, it is not all at once.
I don't think its necessarily a fill rate issue, more to do with how you are handling the actual transition itself. Hense everyone referring to 'pop' in the movement sense. Sudden and Jarring.
For a more indepth discussion, I suggest reading this paper: http://www.cg.tuwien.ac.at/research/publications/2007/GIEGL-2007-UNP/GIEGL-2007-UNP-Preprint.pdf which covers some of the different transition methods. (I believe black & white uses "geomorphing" which may be feasible for your world due to the generated nature of the objects)
Absolutely loved the mountain view at 3:08. I guess my input this time would be that maybe the trees need more roots. That will add a little more variety to the ground and blend the trees into the landscape a little more.
Have you considered adding grape vines and other ropey plants? In my part of the world, which looks a lot like this video, we have wild grape vines that add a lot of interesting detail to our forests. Also they're fun to climb and swing on.
absolutely amazing progress, i check this blog multiple times a week and am always impressed with the results!
like everyone else here mentions, transitions are hurting this the most. i would almost give up the last level of detail just to not have that jarring cross fade transition. geomorphing and not updating the lod for everything uniformly sound like good ideas. another idea, do the push back of lod based upon peoples connection speed?
lastly the darkplaces engine has an interesting take on global illumination, its open source so you can probably contact the creator and just ask him how he managed it. it wouldn't however work as well for such large scenes but you could possibly cascade it.
Long time lurker here, Love that video. The atmosphere is great, just get a little further off the ground, smoothen the ride a bit, and make the walking noises less monotonous (maybe space the steps slightly arbitrarily? Nobody walks on terrain in one pace).
I also have a challenge: generate agricultural landscape: fields with crops that align logically to the landscape, and to roads etc with hedges and fences along the boundaries. I have searched a long time and found NÒT ONE project that procedurally generates agricultural landscape (There is a marked for this) maybe use a cell generation algorithm with the ceed points arranged along height-lines? Looking forward to seeing results :P
Yep, I saw that one a month ago. However, the fields generated in this report are very primitive. Not much more than a separate plot without a house on it. I would like to see someone give this: http://www.webbaviation.co.uk/gallery/d/47430-1/Bosworthfield-aa06487b.jpg a try The more medieval looking equivalent is, off course, also welcome.
As everyone said, the LOD definitely needs work, it is really just too jarring, and really destroys part of the experience. Even if you leave out the closest level of detail, it would be better than the jarring LOD change.
Furthermore, the leaves (especially in the beginning) kinda look like they were painted with a brush =3. Which isn't necessarily a bad thing.
Very nice. That is undeniably a place.
ReplyDeleteThat's weird, I soon stopped looking at the shadows and the LOD transitions, I was simply walking around a nice place, looking at both the grass and the weird mountains.
ReplyDeleteNo idea how all this will look at the end, but will be awesome. Even just as a "trekking" simulator!
This is just stunning. At 2:40 when you can see the far hillside, that view just left me speechless. Really beautiful work!
ReplyDeleteCouple of points about the sound:
a) footsteps are way too loud and consistent. There's also something wrong with the spacing of the sounds vs the speed of movement.
b) bird songs need to be 'located' somehow, so if you're walking around they get louder and softer according to distance. That may not be possible or viable, of course. :)
PS. I really like the geology in this video!
Very cool! My only complaint would be the popping in effect of everything.
ReplyDeleteWith respect to the popping, is the data still being streamed at some throttled rate and that's why there's as much popping close in?
DeleteAlso, are you using billboards for distant terrain or is that all just descending complexity to the horizon?
Yes, popping is evident because it happens too close to the viewer. A simple solution is to push LOD switches further from the view, but this also means you must buffer a lot more and this may not be possible all the time.
DeleteNow, you would also notice foliage changes are far more noticeable than the terrain. This is due to the billboard resolution changing from one LOD to the next. I would like to have a consistent resolution across all LOD, but this would hurt the framerate.
Perhaps for the popping issue, could you make it so that it staggers the popping? It could be a quick and dirty way to get more milage out of your current method. I think the most jarring is when a good portion of the screen changes all at once. If it were done on a more random basis, it could trigger one of those optical illusion things that our brain does to ignore missing details. ( I dodn't know the name, but refer http://www.ted.com/talks/dan_dennett_on_our_consciousness.html @ 17min)
ReplyDeleteAnother thing to address it would be some type of mip-map merging transitons. If you were to change the texture and the model separately (especially with the leaf volumes on the trees) Once the texture is decoupled, it could be faded in more slowly for a less jarring transition like a cross-blur or simple alpha blend. Of course you would also need to use a range based system to avoid flickering, but I suspect you already are using that for the pop system.
lastly, with the tree leaves waving back and forth, your pop has both a geometry, and a movement disparity that is likely triggering our "uncanny valley" response.
The game "Black & White" used the texture transitioning effect, and it's terrain had an interesting tessellation method that meant for more fine-grained LOD. Similarly, it had some ability to warp polygons to shape as you got closer. That game was known for it's amazing LOD system at the time, so it could be something to emulate. http://www.youtube.com/watch?v=1BTAI8KXeH8&t=2m0s Especially interesting was how it layered in the detail texture on the terrain, that part always amazed me.
Basically, the biggest way to get rid of LOD issues is to treat it more similarly to how the human eye focuses on things. As you get closer, they transition to more detail gradually, or if they are suddenly transitioned, it is not all at once.
I don't think its necessarily a fill rate issue, more to do with how you are handling the actual transition itself. Hense everyone referring to 'pop' in the movement sense. Sudden and Jarring.
For a more indepth discussion, I suggest reading this paper: http://www.cg.tuwien.ac.at/research/publications/2007/GIEGL-2007-UNP/GIEGL-2007-UNP-Preprint.pdf which covers some of the different transition methods. (I believe black & white uses "geomorphing" which may be feasible for your world due to the generated nature of the objects)
Absolutely loved the mountain view at 3:08. I guess my input this time would be that maybe the trees need more roots. That will add a little more variety to the ground and blend the trees into the landscape a little more.
ReplyDeleteHave you considered adding grape vines and other ropey plants? In my part of the world, which looks a lot like this video, we have wild grape vines that add a lot of interesting detail to our forests. Also they're fun to climb and swing on.
absolutely amazing progress, i check this blog multiple times a week and am always impressed with the results!
ReplyDeletelike everyone else here mentions, transitions are hurting this the most. i would almost give up the last level of detail just to not have that jarring cross fade transition. geomorphing and not updating the lod for everything uniformly sound like good ideas. another idea, do the push back of lod based upon peoples connection speed?
lastly the darkplaces engine has an interesting take on global illumination, its open source so you can probably contact the creator and just ask him how he managed it. it wouldn't however work as well for such large scenes but you could possibly cascade it.
excellent work!
http://www.youtube.com/watch?v=8-5Z_031x00
ReplyDeletehttp://www.youtube.com/watch?v=tw1GncYrowc
Long time lurker here,
ReplyDeleteLove that video. The atmosphere is great, just get a little further off the ground, smoothen the ride a bit, and make the walking noises less monotonous (maybe space the steps slightly arbitrarily? Nobody walks on terrain in one pace).
I also have a challenge: generate agricultural landscape: fields with crops that align logically to the landscape, and to roads etc with hedges and fences along the boundaries. I have searched a long time and found NÒT ONE project that procedurally generates agricultural landscape (There is a marked for this) maybe use a cell generation algorithm with the ceed points arranged along height-lines? Looking forward to seeing results :P
ScrapHeap
Funny you should say that:
Deletehttp://hal.inria.fr/docs/00/69/45/25/PDF/template.pdf
Yep, I saw that one a month ago.
DeleteHowever, the fields generated in this report are very primitive. Not much more than a separate plot without a house on it. I would like to see someone give this: http://www.webbaviation.co.uk/gallery/d/47430-1/Bosworthfield-aa06487b.jpg a try
The more medieval looking equivalent is, off course, also welcome.
ScrapHeap
As everyone said, the LOD definitely needs work, it is really just too jarring, and really destroys part of the experience. Even if you leave out the closest level of detail, it would be better than the jarring LOD change.
ReplyDeleteFurthermore, the leaves (especially in the beginning) kinda look like they were painted with a brush =3. Which isn't necessarily a bad thing.