Title: Orthogonal projection + slicing Post by: Patryk Kizny on June 13, 2015, 06:07:54 PM Hey,
Trying to recreate mandelbulb-like voxel rendering in fragmentarium. I added simple fractal slicing and tweaking a bit with coloring allows for more less BW export. I wonder how to get orthogonal projection in the DE-raytracer. I guess it is orthogonal at FOV = 0 (out of the box), but that won't work. Can anybody post a tweak to get simple ortho projection with the latest DE-raytracer? i guess thaat should be a piece of cake for the authors of the tracer. Much appreciated. Second thing - can you guys elaborate on simple tweaks to get rid of fractal 'interior' meat when rendering slices (I'm just clipping output with a thin box volume). Thanks! Title: Re: Orthogonal projection + slicing Post by: 3dickulus on June 13, 2015, 07:02:20 PM look in Examples/
try the 2D camera or use an "ortho" function as in IBL-Pathtracer.frag... Code: vec3 ortho(vec3 d) {Title: Re: Orthogonal projection + slicing Post by: 3dickulus on June 14, 2015, 12:33:59 AM are you looking for single pixel slices for building a point cloud from a series of images? there might already be such thing, maybe re:3Dprinting
p.s... the ortho function above (probably not what you want) would need to be tailored to your needs of course. Title: Re: Orthogonal projection + slicing Post by: Patryk Kizny on June 14, 2015, 01:06:20 PM Yes Dick, the ultimate goal is to implement pointcloud export.
As far as I understand doing it the proper way from scratch would be demanding as requires different approach than the one used for rendering. But since we already have a good workflow for automated merging of BW slice images into pointlclouds in Krakatoa I was thinking about a simple workaround and using existing DE-raytracer with a few changes to render out a sequence. If you have any better ideas - let me know. This morning I also had a thought - there are many folks interested in printing stuff and the workflow usually assumed rendering voxels, recreating object mesh and then STLing to print. Full of artifacts. But actually I don't see anything against one writing a program to directly print using the DE-estimation method. Or I missed something and it looks like daydreaming? Title: Re: Orthogonal projection + slicing Post by: 3dickulus on June 14, 2015, 01:27:48 PM using the "search" box (top right) type in point cloud and click the search button, you will see a lot of posts, some may have code or give you an idea of how to do it. I haven't looked into it specifically for Fragmentarium.
Title: Re: Orthogonal projection + slicing Post by: Syntopia on June 14, 2015, 10:44:31 PM The 'ortho' function is for creating an arbitrary orthogonal vector. It is not related to orthographic perspective. But I don't think you should use any projection if you want to render slices. Instead render the fractal in 2D. Look at 'examples/theory/mandelbulb-slicer.frag'. There are four panels when it runs: the lower left is a 2D slice.
This morning I also had a thought - there are many folks interested in printing stuff and the workflow usually assumed rendering voxels, recreating object mesh and then STLing to print. Full of artifacts. But actually I don't see anything against one writing a program to directly print using the DE-estimation method. Or I missed something and it looks like daydreaming? I did some time ago, while playing around with OpenGL in Java. I did a gpu accelerated DE -> OBJ exporter (using marching cubes which is the standard method). I created a few 3D prints using this technique: http://www.shapeways.com/product/GQMXP6ZMX/mandelbulb-iii The code is online (at https://github.com/Syntopia/Meshia/tree/master/meshia/src/net/hvidtfeldts) but it is to much of a mess to be really usable - but the marching cube implementation may serve as inspiration. Title: Re: Orthogonal projection + slicing Post by: Patryk Kizny on June 15, 2015, 10:48:07 AM Nice one, thanks! |