D'oh! YEARS I've wasted not knowing this.
And of course now the knowledge has an expiration date. On Tue, Jun 24, 2014 at 8:11 PM, Matt Lind <ml...@carbinestudios.com> wrote: > You don't need expressions. The rotation can be corrected with a > create_transform node: > > 1) Render > [Render] Render > Pass Options... > 2) In the pass PPG, click the Environment's "Add" button and choosing > "Environment" shader from the popup dialog. Double click the shader to > inspect in a PPG. > - choose your image > - adjust shader settings as desired. > 3) Open scene explorer and press "U" to inspect the current pass. > 4) Select the "Environment" property under the pass root. > 5) Press "7" to open the rendertree. You should see the blue > "Environment" shader connected to the orange current Pass. Your image clip > should be connected to the "tex" input of the environment shader. > 6) From the shader presets, click and drag Processing > Math > > Create_transform into the rendertree workspace. Connect its output to the > "transform" input of the environment shader. > - adjust transform as desired. > > > Matt > > > > > > -----Original Message----- > From: softimage-boun...@listproc.autodesk.com [mailto: > softimage-boun...@listproc.autodesk.com] On Behalf Of Nancy Jacobs > Sent: Tuesday, June 24, 2014 2:27 PM > To: softimage@listproc.autodesk.com > Subject: Re: Ideas for star fields? > > Good point, if I use expressions to correct the rotation problems re the > environment map and any SI world null rotation parameters... They have to > be connected in a strange manner, at least as of 2014. Don't imagine > they've fixed that... > > Thanks, > Nancy > > On Jun 24, 2014, at 1:22 PM, Matt Lind <ml...@carbinestudios.com> wrote: > > > If you're just going to create a sphere with specks on it, why don't you > use an environment shader? That does the same work without having to > create a sphere, deal with camera rigs, or mess up your ray depth > computations in the render. > > > > > > Matt > > > > > > > > > > > > > > > > -----Original Message----- > > From: softimage-boun...@listproc.autodesk.com > > [mailto:softimage-boun...@listproc.autodesk.com] On Behalf Of > > Ponthieux, Joseph G. (LARC-E1A)[LITES] > > Sent: Tuesday, June 24, 2014 6:25 AM > > To: softimage@listproc.autodesk.com > > Subject: RE: Ideas for star fields? > > > > Oh and one other thing. You may find that constraining the star field > sphere position directly to your camera and forcing the sphere orientation > to remain in sync with the scene will produce the best results. Render the > stars out as a pass and comp everything over them as the base image. By > doing this the "stars" will always maintain an exact distance from the > camera and since stars are such an incredible distance from us in space the > illusion is remarkably similar. It will also make the appearance of the > stars much more predictable as you can set them for what you want and you > no longer have to worry about that appearance changing other than camera > orientation. > > > > -- > > Joey Ponthieux > > LaRC Information Technology Enhanced Services (LITES) Mymic Technical > > Services NASA Langley Research Center > > __________________________________________________ > > Opinions stated here-in are strictly those of the author and do not > represent the opinions of NASA or any other party. > > > > > >> -----Original Message----- > >> From: softimage-boun...@listproc.autodesk.com [mailto:softimage- > >> boun...@listproc.autodesk.com] On Behalf Of Ponthieux, Joseph G. > >> (LARC- E1A)[LITES] > >> Sent: Tuesday, June 24, 2014 9:13 AM > >> To: softimage@listproc.autodesk.com > >> Subject: RE: Ideas for star fields? > >> > >> The problem is that you are using Hubble images. Hubble images are > >> high res and beautiful but often are only representative of a single > >> focal point in space. What you want is a "star map" that is a > >> cylindrical projection suited for your sphere. You will find the maps > >> you need at this link. In particular the high res Tycho maps are > probably what you want. > >> > >> http://svs.gsfc.nasa.gov/vis/a000000/a003500/a003572/ > >> > >> When you map these onto your sphere you will notice that the center > >> of your sphere of the focal point of a "disc" or "ring" of stars. > >> You'll see the "ring" form on the inner side of the sphere. There > >> were three maps historically, Tycho, Hipparcos, and Yale. The > >> following links contain them but these do not look like the highest res > versions. > >> > >> http://www.nasa.gov/multimedia/3d_resources/assets/tycho8.html > >> > >> http://www.nasa.gov/multimedia/3d_resources/assets/hipp8.html > >> > >> http://www.nasa.gov/multimedia/3d_resources/assets/yale8.html > >> > >> > >> Each was created at different resolutions and star counts. One is > >> synthetic I think, and that I believe is the Yale map based upon the > >> Tycho catalog. The map is of higher contrast and may lack a lot of > >> the intermediate or diminished stars so it may be useful in some > >> circumstances. You'll have to figure out what the basic appearance is > >> that you are looking for and a combination of the maps may be what > >> you want. As you probably have already discovered, you won't be able to > let your camera get too close to the texture surface as > >> the stars will become abnormally large and the illusion will be lost. > Its best if > >> you scale the sphere as large as you can and keep the surface as far > >> from the camera as possible to reach the effect you want. > >> > >> If you want a moving starfield, the best way to achieve that is > >> generate a massive field of small triangles set to constant white. > >> The distance apart, size, and randomness will have to be worked out. > >> You can do this as particles as well, but if the particles are set to > >> pixel height you'll lose the sense of perspective and distance as you > fly through them. > >> > >> -- > >> Joey Ponthieux > >> LaRC Information Technology Enhanced Services (LITES) Mymic Technical > >> Services NASA Langley Research Center > >> __________________________________________________ > >> Opinions stated here-in are strictly those of the author and do not > >> represent the opinions of NASA or any other party. > >> > >>> -----Original Message----- > >>> From: softimage-boun...@listproc.autodesk.com [mailto:softimage- > >>> boun...@listproc.autodesk.com] On Behalf Of Nancy Jacobs > >>> Sent: Monday, June 23, 2014 5:43 PM > >>> To: Softimage Listserve > >>> Subject: Ideas for star fields? > >>> > >>> Hello, > >>> > >>> I'm needing a star field kind of background for a scene, and looking > >>> for > >> ideas > >>> to create it. I have been using Hubble images wrapped around a > >>> sphere, around the scene, but I'm finding it doesn't read well, even > >>> with very high- res Hubble images. > >>> > >>> So, I'm wondering about other ways to create star fields. Has to be > >>> 360 degrees, seamlessly -- and I don't have the capability to deal > >>> with that in a compositing situation. > >>> > >>> So....any ideas? > >>> > >>> Thanks, > >>> Nancy > > > > > > > > >
