Re: [osg-users] rain/snow accumulation on the screen
Hi all, I am also looking into this issue like Nik. the needs are: 1.Rain drops must appear on the screen when in fps (car driving) camera mode 2.They dont need to move, but their numbers will increase in time and make it difficult to see the environment. 3.When activated a wiper will rotate on the screen, clearing the raindrops as it touches them. similarly snow will accumulate on the windshield and wiper will clean them too. Can this be done with osg particle classes? What kind of new functionality may be needed if particle system is not enough to handle these tasks ? Or what specific features of osg can accomplish such tasks? Thanks in advance for any hints. -- Read this topic online here: http://forum.openscenegraph.org/viewtopic.php?p=34695#34695 ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] rain/snow accumulation on the screen
I'm going to preface my comment by saying I've never done an effect like this before. I am, however, interested in how this could be accomplished. Adding in the wiper effect adds a particularly difficult layer of complexity to an effect like this. I would still suggest using a shader to do this effect. You would have to update the wiper's position as a uniform value per frame. You can then choose to apply the raindrop texture to pixels on one side of the wiper and then dont apply the texture to pixels on the other side of the wiper. You can also do this if your procedurally creating the raindrops on the fly. Cheers, Steven -- Read this topic online here: http://forum.openscenegraph.org/viewtopic.php?p=34720#34720 ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] rain/snow accumulation on the screen
robertosfield wrote: Hi Nick, On Wed, Dec 1, 2010 at 10:15 AM, Trajce (Nick) Nikolov wrote: any ideas/hints how to implement rain/snow accumulation on the screen (like for a driving sim)? Bring a laptop to Scotland and sit outside. Right now you'll get an accumulation of snow on the screen. Waiting another week and we might be able to provide an accumulation of rain, although it's likely to ruin the laptop. Still you'd have achieved your mission :-) Robert. ___ osg-users mailing list http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org -- Post generated by Mail2Forum I spent a winter in Edinburgh as a young boy! Don't care to relive that winter again if I can help it! B, it defined cold for me! Thanks but no Thanks Robert! I guess that I have had all the Scotsman bred out of me in Sothern California, because I’d rather spend my winter near the Med if I got to live in that part of the world! Of course I also had issues with the schooling I got back then also - they maid you learn! D Glenn (a.k.a David Glenn) - Join the Navy and See the World ... from your Desk! -- Read this topic online here: http://forum.openscenegraph.org/viewtopic.php?p=34567#34567 ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] rain/snow accumulation on the screen
I'd use a pixel shader for the effects. Pass in the texture that represents the snow overlay and have the shader scale the alpha up and down as it accumulates. Rain would be handled the same way but you'd have to come up with a way to make the water droplets move around on the screen. That should be possible in the shader as well. Thank you! Cheers, Steven -- Read this topic online here: http://forum.openscenegraph.org/viewtopic.php?p=34455#34455 ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] rain/snow accumulation on the screen
Thanks Steven .. good hint! -Nick On Thu, Dec 2, 2010 at 11:56 PM, Steven Powers stevenapow...@gmail.comwrote: I'd use a pixel shader for the effects. Pass in the texture that represents the snow overlay and have the shader scale the alpha up and down as it accumulates. Rain would be handled the same way but you'd have to come up with a way to make the water droplets move around on the screen. That should be possible in the shader as well. Thank you! Cheers, Steven -- Read this topic online here: http://forum.openscenegraph.org/viewtopic.php?p=34455#34455 ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
[osg-users] rain/snow accumulation on the screen
Hi Community, any ideas/hints how to implement rain/snow accumulation on the screen (like for a driving sim)? -Nick ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] rain/snow accumulation on the screen
Hi Nick, On Wed, Dec 1, 2010 at 10:15 AM, Trajce (Nick) Nikolov nikolov.tra...@gmail.com wrote: any ideas/hints how to implement rain/snow accumulation on the screen (like for a driving sim)? Bring a laptop to Scotland and sit outside. Right now you'll get an accumulation of snow on the screen. Waiting another week and we might be able to provide an accumulation of rain, although it's likely to ruin the laptop. Still you'd have achieved your mission :-) Robert. ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] rain/snow accumulation on the screen
Hahahahahahah ... thanks Robert !!! -Nick On Wed, Dec 1, 2010 at 2:44 PM, Kim Bale kcb...@googlemail.com wrote: Genius. :) K. On 1 December 2010 10:24, Robert Osfield robert.osfi...@gmail.com wrote: Hi Nick, On Wed, Dec 1, 2010 at 10:15 AM, Trajce (Nick) Nikolov nikolov.tra...@gmail.com wrote: any ideas/hints how to implement rain/snow accumulation on the screen (like for a driving sim)? Bring a laptop to Scotland and sit outside. Right now you'll get an accumulation of snow on the screen. Waiting another week and we might be able to provide an accumulation of rain, although it's likely to ruin the laptop. Still you'd have achieved your mission :-) Robert. ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] rain/snow accumulation on the screen
actually, not a a bad idea ... people with John Nesh fortune could probably figure out the algorithm then ;-) -Nick On Wed, Dec 1, 2010 at 4:43 PM, Trajce (Nick) Nikolov nikolov.tra...@gmail.com wrote: Hahahahahahah ... thanks Robert !!! -Nick On Wed, Dec 1, 2010 at 2:44 PM, Kim Bale kcb...@googlemail.com wrote: Genius. :) K. On 1 December 2010 10:24, Robert Osfield robert.osfi...@gmail.comwrote: Hi Nick, On Wed, Dec 1, 2010 at 10:15 AM, Trajce (Nick) Nikolov nikolov.tra...@gmail.com wrote: any ideas/hints how to implement rain/snow accumulation on the screen (like for a driving sim)? Bring a laptop to Scotland and sit outside. Right now you'll get an accumulation of snow on the screen. Waiting another week and we might be able to provide an accumulation of rain, although it's likely to ruin the laptop. Still you'd have achieved your mission :-) Robert. ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] rain/snow accumulation on the screen
On 1/12/2010 6:15 PM, Trajce (Nick) Nikolov wrote: Hi Community, any ideas/hints how to implement rain/snow accumulation on the screen (like for a driving sim)? -Nick A company I used to work for which did driving sims, mining trucks in fact, just used a series of bitmaps - I might be using totally the wrong buzzwords here, I've had my after work beer and the correct terms escape me. The bit maps were generated by the graphics people and we just loaded them up and overlayed them as needed. There was a series of overlays that corresponded to: 1) A few drops 2) More drops 3) Even more drops 4) quite a few drops ... ... ... ... n) That many drop that in combination with a dusty windscreen, remember this is of a mining truck in an iron ore mine in Australia, that the windscreen has become mud. Then the user would turn on the wipers and a new set of overlays would be used which corresponded to the windscreen wipers going. These overlays were created by our graphic artists and we just dumped them into the scene at the speed we needed to simulate the rain. In other words the screen/rain/mud was not done dynamically with a snazzy algorithm, it was basically good old page flipping animation. Nick, does this make sense? If not I'll revisit the topic in the morning, it's currently 11.15pm, and try and make more sense. Regards, Andrew ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] rain/snow accumulation on the screen
Pixelmaps or billboard textures might be the OpenGL terminology. Animation studios might use the term Particle Systems. 1980's game programmers would probably use the term sprites, especially if their motion changed when you moved. In this case blowing off as the vehicle moved. For snow, they would be partially transparent at the edges (alpha -0 ) and darker in the middle, so that when they were pasted on top together, they would make that area of the screen go dark. Not sure about the description of rain accumulation - if it were the effect of water trickling down the window, Doing trickling raindrops would be tricky - you would definitely need a particle system with a surface threshold algorithm (marching cubes/triangles) and some surface tension physics to generate the geometry to do refraction. On the inside of the window, you'd want condensation effects - that would just be partially transparent gray. On Wed, Dec 1, 2010 at 3:17 PM, Andrew Lowe a...@wht.com.au wrote: On 1/12/2010 6:15 PM, Trajce (Nick) Nikolov wrote: Hi Community, any ideas/hints how to implement rain/snow accumulation on the screen (like for a driving sim)? -Nick A company I used to work for which did driving sims, mining trucks in fact, just used a series of bitmaps - I might be using totally the wrong buzzwords here, I've had my after work beer and the correct terms escape me. The bit maps were generated by the graphics people and we just loaded them up and overlayed them as needed. There was a series of overlays that corresponded to: 1) A few drops 2) More drops 3) Even more drops 4) quite a few drops ... ... ... ... n) That many drop that in combination with a dusty windscreen, remember this is of a mining truck in an iron ore mine in Australia, that the windscreen has become mud. Then the user would turn on the wipers and a new set of overlays would be used which corresponded to the windscreen wipers going. These overlays were created by our graphic artists and we just dumped them into the scene at the speed we needed to simulate the rain. In other words the screen/rain/mud was not done dynamically with a snazzy algorithm, it was basically good old page flipping animation. Nick, does this make sense? If not I'll revisit the topic in the morning, it's currently 11.15pm, and try and make more sense. Regards, Andrew ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] rain/snow accumulation on the screen
Thank you !!! Andrew, your approach was the first that crossed my mind But not too much of a fan of it. More into what Michael is proposing ... Thanks again -Nick On Wed, Dec 1, 2010 at 7:56 PM, Michael Robb msar2...@gmail.com wrote: Pixelmaps or billboard textures might be the OpenGL terminology. Animation studios might use the term Particle Systems. 1980's game programmers would probably use the term sprites, especially if their motion changed when you moved. In this case blowing off as the vehicle moved. For snow, they would be partially transparent at the edges (alpha -0 ) and darker in the middle, so that when they were pasted on top together, they would make that area of the screen go dark. Not sure about the description of rain accumulation - if it were the effect of water trickling down the window, Doing trickling raindrops would be tricky - you would definitely need a particle system with a surface threshold algorithm (marching cubes/triangles) and some surface tension physics to generate the geometry to do refraction. On the inside of the window, you'd want condensation effects - that would just be partially transparent gray. On Wed, Dec 1, 2010 at 3:17 PM, Andrew Lowe a...@wht.com.au wrote: On 1/12/2010 6:15 PM, Trajce (Nick) Nikolov wrote: Hi Community, any ideas/hints how to implement rain/snow accumulation on the screen (like for a driving sim)? -Nick A company I used to work for which did driving sims, mining trucks in fact, just used a series of bitmaps - I might be using totally the wrong buzzwords here, I've had my after work beer and the correct terms escape me. The bit maps were generated by the graphics people and we just loaded them up and overlayed them as needed. There was a series of overlays that corresponded to: 1) A few drops 2) More drops 3) Even more drops 4) quite a few drops ... ... ... ... n) That many drop that in combination with a dusty windscreen, remember this is of a mining truck in an iron ore mine in Australia, that the windscreen has become mud. Then the user would turn on the wipers and a new set of overlays would be used which corresponded to the windscreen wipers going. These overlays were created by our graphic artists and we just dumped them into the scene at the speed we needed to simulate the rain. In other words the screen/rain/mud was not done dynamically with a snazzy algorithm, it was basically good old page flipping animation. Nick, does this make sense? If not I'll revisit the topic in the morning, it's currently 11.15pm, and try and make more sense. Regards, Andrew ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
