Re: [osg-users] Shadows : Creating multiple osgShadow::ShadowedScene
Hi Robert, On 29 May 2015 at 03:41, Robert Graf muzzlebu...@gmail.com wrote: Do you or anyone else here know if the view dependent shadow map in the OSG is based on the method of the following master thesis? I read a number of different papers, tried different implementations and came up with an approach that worked well for decent range of scenes. The technique also embodies several approaches - it supports multiple shadow maps and perspective shadow maps. It essentially boils down to rendering the scene from the light source direction, adjusting the frustum to provide better correlation between shadow texels and final screen space projection of the shadow map - all depth texture based shadow techniques use this broad approach, the different boils down to the management of the view frustum of the shadow render pass. Robert ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] Shadows : Creating multiple osgShadow::ShadowedScene
Thanks for the guidance on this Robert, it is great to know! Do you or anyone else here know if the view dependent shadow map in the OSG is based on the method of the following master thesis? Understanding the methodology of the technique will help me better understand the code in order to modify it. http://dcgi.felk.cvut.cz/theses/2010/hinkjan Thanks a bunch! -Robert -- Read this topic online here: http://forum.openscenegraph.org/viewtopic.php?p=63879#63879 ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] Shadows : Creating multiple osgShadow::ShadowedScene
Hi Robert, osgShadow doesn't currently have an ShadowTechniques that support multiple light sources, the closest to this is the ViewDependentShadowMap with it's support for multiple shadow maps, which currently is related to it's support of depth partitioning of the shadow map, but I've had it in mind that this would be generalized at a later date to support multiple light sources as well. This would require support in the shaders as well as the .cpp. Have a look at how it's implemented. You could implement your own ShadowTechinque using a similar approach, or subclass from ViewDependentShadowMap. I wouldn't recommend the approach you are suggesting though, using multiple ShadowedScene's would just complicate implementation and usage. Robert. On 25 May 2015 at 02:26, Robert Graf muzzlebu...@gmail.com wrote: Howdy all, What is a way to have a ShadowedScene update just its shadow texture unit in the pre-render for its children, and not have its children rendered during the main viewer pass? I'd like to set up multiple lights, each with its own shadow map. Each light/shadowmap combination will be a ShadowedScene. These ShadowedScene's will be pre-rendered, each in their own shadow map texture unit. Then in the main viewer pass, a custom fragment shader will use the different shadow map texture units for shadowing. For the main viewer pass, only the regular scene will be rendered, not any of the shadowed_scene's. The scene would look something like this: - root |--- shadowed_scene1 | |--- scene |--- shadowed_scene2 | |--- scene |--- shadowed_scene3 | |--- scene |--- scene Thanks! -Robert -- Read this topic online here: http://forum.openscenegraph.org/viewtopic.php?p=63804#63804 ___ 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] Shadows : Creating multiple osgShadow::ShadowedScene
Howdy all, What is a way to have a ShadowedScene update just its shadow texture unit in the pre-render for its children, and not have its children rendered during the main viewer pass? I'd like to set up multiple lights, each with its own shadow map. Each light/shadowmap combination will be a ShadowedScene. These ShadowedScene's will be pre-rendered, each in their own shadow map texture unit. Then in the main viewer pass, a custom fragment shader will use the different shadow map texture units for shadowing. For the main viewer pass, only the regular scene will be rendered, not any of the shadowed_scene's. The scene would look something like this: - root |--- shadowed_scene1 | |--- scene |--- shadowed_scene2 | |--- scene |--- shadowed_scene3 | |--- scene |--- scene Thanks! -Robert -- Read this topic online here: http://forum.openscenegraph.org/viewtopic.php?p=63804#63804 ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] Shadows : Creating multiple osgShadow::ShadowedScene
Howdy all, What are some approaches for using the OSG to render a scene with 6 shadow-casting spot lights using the ShadowMap technique? A couple of ideas that came to mind: 1) Use multiple ShadowedScene's with each one having a ShadowMap technique that sets a unique shadow texture unit for each shadow map. ShadowMap has a function setTextureUnit() for doing this. Could these shadowed scenes be rendered in a pre-pass, such as under a slave camera or RenderBins, and have the resulting shadow texture units be available for a main-pass fragment shader? 2) Make a local clone of ShadowMap, and modify it to support 6 lights with a dedicated shadow texture unit for each light. A fragment shader would be added using the ShadowMap.addShader() method, that does per-pixel lighting and does look-ups into all 6 shadow texture units. 3) Make a local clown of ShadowedScene, and modify it so that _shadowSettings and _shadowTechnique are dynamic arrays, effectively allowing multiple ShadowSettings/ShadowTechnique pairs to be inserted. Each inserted ShadowMap technique would be assigned a unique texture unit number. This has a number of questionable architecture issues. Something similar to #1 above would be ideal, without modifying OSG much, but may not be possible. #2 seems like it should work, but would require some development. #3 sounds like it would be over-complicated or unfitting for the OSG framework. Any thoughts or opinions? Thanks guys! -Robert Graf -- Read this topic online here: http://forum.openscenegraph.org/viewtopic.php?p=63762#63762 ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] Shadows : Creating multiple osgShadow::ShadowedScene
Let's take an example: ShadowTechnique SHADOWMAP It creates a texture and installs a shader program which makes shadow effects by using the created texture. So what you think happens by the second shadowScene? On traversal it will create a new texture, by default install it in the same texture unit, and install a shader using just this newly created shadow texture. What you expect is a shader program using 2 shadow textures. But this one you have to write yourself. - Werner - On Tuesday 28 September 2010 06:29:50 Saravanan Sivaprahasam wrote: Thanks for the reply. But could any one explain me why it is not possible to add two osgShadow::ShadowedScene to the root node Thank you! Cheers, Saravanan -- Read this topic online here: http://forum.openscenegraph.org/viewtopic.php?p=32115#32115 ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org -- TEXION Software Solutions TEXION GmbH - Rotter Bruch 26a - D 52068 Aachen - HRB 14999 Aachen Fon: +49 241 475757-0, Fax: +49 241 475757-29, web: http://www.texion.eu Geschäftsführer/Managing Director: Werner Modenbach ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
[osg-users] Shadows : Creating multiple osgShadow::ShadowedScene
Hi, I'm rendering shadows using osgShadow::ShadowMap method. For large outdoor scenes with various objects, the rendered shadows look pixelated and self shadows on objects are not correct. I've increased the shadow map resolution to 4096, but still it is not correct. So i have created two shadowed scenes (osgShadow::ShadowedScene ) each having a separate light source and shadow map of 4096 resolution. The second osgShadow::ShadowedScene that is added (last) as a child to root node is getting rendered, while the first shadowed scene added to root is not getting rendered. Please provide some suggestions to get the shadows rendered correctly Thank you! Cheers, Saravanan -- Read this topic online here: http://forum.openscenegraph.org/viewtopic.php?p=32093#32093 ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
Re: [osg-users] Shadows : Creating multiple osgShadow::ShadowedScene
Hi Saravanan, Try other shadowing techniques, Parallel Split Shadow Maps (pssm) or Light Space Perspective Shadow Maps (lispsm). They should be better suited for your case. Cheers, Wojtek Lewandowski -- From: Saravanan Sivaprahasam saransivapraha...@rediffmail.com Sent: Monday, September 27, 2010 2:18 PM To: osg-users@lists.openscenegraph.org Subject: [osg-users] Shadows : Creating multiple osgShadow::ShadowedScene Hi, I'm rendering shadows using osgShadow::ShadowMap method. For large outdoor scenes with various objects, the rendered shadows look pixelated and self shadows on objects are not correct. I've increased the shadow map resolution to 4096, but still it is not correct. So i have created two shadowed scenes (osgShadow::ShadowedScene ) each having a separate light source and shadow map of 4096 resolution. The second osgShadow::ShadowedScene that is added (last) as a child to root node is getting rendered, while the first shadowed scene added to root is not getting rendered. Please provide some suggestions to get the shadows rendered correctly Thank you! Cheers, Saravanan -- Read this topic online here: http://forum.openscenegraph.org/viewtopic.php?p=32093#32093 ___ 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] Shadows : Creating multiple osgShadow::ShadowedScene
Thanks for the reply. But could any one explain me why it is not possible to add two osgShadow::ShadowedScene to the root node Thank you! Cheers, Saravanan -- Read this topic online here: http://forum.openscenegraph.org/viewtopic.php?p=32115#32115 ___ osg-users mailing list osg-users@lists.openscenegraph.org http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
