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About PolyVox

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  1. Might be worth checking this out: http://mosra.cz/blog/magnum.php
  2. Approximation of Normals in Screen Space

    If I understand you correctly then you can use the ddx/ddy instructions to compute a per-pixel normal in the fragment shader:   http://c0de517e.blogspot.nl/2008/10/normals-without-normals.html   I also have a code snippet here:   http://www.volumesoffun.com/polyvox/documentation/0.2.1/manual/Lighting.html#normal-calculation-for-cubic-meshes   Note that you will typically end up with a faceted appearance rather than smooth shading (which is fine for my application).
  3. I'm not sure if you seen it (or if it's useful) but Game Engine Gems 3 had an article on doing traditional stencil shadows in the geometry shader. Maybe you can modify that? See it here: http://http.developer.nvidia.com/GPUGems3/gpugems3_ch11.html
  4. Hi all, We've just made a new release of our PolyVox voxel terrain engine. You can read about PolyVox [url="http://www.volumesoffun.com/polyvox-about/"]here[/url] and see a list of projects using it [url="http://www.volumesoffun.com/polyvox-projects/"]here[/url]. Some key points:[list] [*]Written in C++ and available under the zlib license. [*]Independent of graphics API or rendering engine. [*]Can create both smooth and cubic-style terrain. [*]Raycasting support for picking and ambient occlusion. [*]Support for large volumes with compression and paging. [*]Provides image processing operations (resampling, blurring, etc). [*]Has an A* implementation for pathfinding through volume data. [/list] The new release contains a number of improvements to both the library and also to the surrounding development process. You can read the release announcement here: [url="http://www.volumesoffun.com/polyvox-version-0-2-released/"]http://www.volumesoffun.com/polyvox-version-0-2-released/[/url] Hope someone finds it useful :-)
  5. gaussian curvature on a 3D mesh

    I'm afraid I don't know about that, I've only used it for basic mesh viewing really.
  6. gaussian curvature on a 3D mesh

    MeshLab appears to have support for [i]mean[/i] curvature: http://meshlabstuff.blogspot.nl/2010/03/mean-curvature-cavity-map-zbrush-and.html Not sure how similar that is but it's open source and may be a starting point...
  7. Volumetric rendering engine or library

    You can check out: http://www.visualizationlibrary.org/ Also VTK might be interesting but it's quite heavyweight: http://www.vtk.org/ They'll both require some significant integration work I think...
  8. You might find the ImageMagick 'compare' tool useful. It has a number of metrics which you can use when comparing images: http://www.imagemagick.org/script/command-line-options.php#metric
  9. FumeFX for Sprites ?

    Also consider [url="http://www.positech.co.uk/content/explosion/explosiongenerator.html"]Explosion Generator[/url]?
  10. Sounds something like this? [url="http://www.ericrisser.com/stuff/Rendering3DVolumesUsingPerPixelDisplacementMapping.pdf"]http://www.ericrisser.com/stuff/Rendering3DVolumesUsingPerPixelDisplacementMapping.pdf[/url] Also looak at True Iposters in GPU Gems 3:[url="http://http.developer.nvidia.com/GPUGems3/gpugems3_ch21.html"]http://http.developer.nvidia.com/GPUGems3/gpugems3_ch21.html[/url]
  11. Voxel "chunk" storage

    In [url="http://www.volumesoffun.com/polyvox-about/"]PolyVox[/url] we seperate the storage of the volume data from the way surface extraction is perfomed. That is, the volume may or may not consist of a set of blocks, and even if it does then the size of these blocks may or may not be the same as the size of the extracted meshes. For example you might decide that 32x32x32 is the ideal size for storing blocks in memory, but 64x64x64 is better for the rendered meshes. Or maybe that you want the rendered blocks to be 16x16x128 but you don't want the memory to be broken into blocks at all (perhaps you'd rather use an octree?). So basically we focus on just providing fast volume data structures which are independant of the algorithm which is executed on them. Surface extraction is just one task you need to perform, and raycasting (for example) can have a different set of characteristics. That doesn't exactly answer your question... but maybe it's something to think about.
  12. Ah, I recognise it now :-) Because of the cars I though it was a museum or something. They must have been added seperatly.
  13. [quote name='Krypt0n' timestamp='1334542709' post='4931611']you can check out some voxel renderings in my gallery: [url="http://twitpic.com/photos/michael_hpp"]http://twitpic.com/photos/michael_hpp[/url] , sometimes I state which version I've used, I think the bottom most picture with the animated imp was CPU.[/quote] Nice pictures! Kind of off topic but where is this scene from: http://twitpic.com/8iohd5/full Is it a freely available test scene or something you aquired privately?
  14. High Quality Test Scenes

    There was another discussion thread recently which had a few good links in it. Check it out here: http://www.gamedev.net/topic/621237-demo-levels-for-engine-development/
  15. a normals problem with voxels

    [quote name='winsrp' timestamp='1332024351' post='4922909'] so the ddx and ddy checks the adjacent pixes, and it kinda makes a fake triangle of pixels to find where the perpendicular value to all 3 is. Right? [/quote] Yeah, I guess you could think of it like that.