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Hi all, Is there a way of creating unlit billboard materials (or unlit materials deriving from mesh_base)? My use case is: I'm rendering a galaxy and there are no light sources within the world. I was using sphere meshes with an emissive material which is working very well. That said, as I'm plotting 100k+ nodes I don't need the geometry overhead of spheres; a flat plane billboard with an alpha texture would easily suffice. I've been playing around with both billboard and mesh_base materials but cannot get them to render visibly without a light in the scene. Any assistance would be greatly received and i hope the above makes some sense. Best regards and many thanks in advance, Matt.

After migrating to version 2.7 repositioning of billboards in my application has drastically slowed done. Actually it's about 20 times slower than in version 2.6.1.1. Here is the code start = std::chrono::high_resolution_clock::now (); for ( int id = 0; id < pBillboadrs->getNumBillboards (); id++ ) { double dRadius = fFarClipping-150.0; int iStarID = mapBillboardID2StarID[id]; double x, y, z; y = dRadius * StarSky[iStarID].ObservParam.Alt.cos () * StarSky[iStarID].ObservParam.Az.cos (); x = dRadius * StarSky[iStarID].ObservParam.Alt.cos () * StarSky[iStarID].ObservParam.Az.sin (); z = dRadius * StarSky[iStarID].ObservParam.Alt.sin (); Math::vec3 position ( x, y, z ); pBillboadrs->setBillboardPosition ( id, position ); } end = std::chrono::high_resolution_clock::now (); auto lag = std::chrono::duration<double, std::ratio<1, 1>> ( end - start ); char str[128]; sprintf_s ( str, 128, "StarSky: 'setBillboardPosition' for %i billboards in %f seconds\n", pBillboadrs->getNumBillboards (), lag.count () ); Log::message ( str ); Number of billboards is 7987. Loop execution time is 0,082163 seconds for version 2.6.1.1 and 1,46314 seconds for vesion 2.7. All math in loop is OK. If I comment line with setBillboardPosition the loop is very fast in all versions. The same problem is with billboards size change. Simular code for changing size has become very slow.

We've been experiencing a bug for a while where our tree billboards would flicker black in a really obnoxious way, that looked a lot like z-fighting. Recently though I've tracked it down and discovered that it isn't caused by z-fighting after all. We assumed it was so dark because it was caused by shadowed billboards being sorted incorrectly and showing up in front of other trees, but it's actually a problem with alpha testing not working properly. The first attached image shows this problem manifesting itself in a line. This is the point where the juniperoxy billboard intersects the willow billboard (the tree). You can see this in the second image where alpha test is turned off for the juniperoxy. Looking at the 4th image, you can see it's not just rendering black pixels there, it's actually rendering the transparent portion of the billboard image as opaque. For some reason when two billboard polys intersect in a certain way, it renders part of the image at 100% opaque alpha. In the short term, I've worked around this by painting a green tree pattern into the black portions of the tree billboards, and it's reduced the amount of flickering the user can see, however it's still very noticeable on groups of trees with some color variation. Is there a fix for this? We're on version 2.2.1, btw.

I noticed a while ago that the billboard lighting changes more dramatically than it should when the camera rotates. Attached are some screenshots illustrating what I mean. The sun angle is almost straight overhead in these. The first screenshot is looking slightly down, and the billboards look ok. The second screenshot is looking straight out over the terrain and the billboards receive no lighting from the sun at all. The third screenshot is looking directly down at the ground, and the billboards receive full lighting. The difference between looking straight across the terrain versus looking down makes it very difficult to balance the ground cover to where it blends overall. I'm also not convinced that the lighting is coming from the correct angle. In the fourth screenshot I circled the sun in red, but the lighting is clearly coming from 90 degrees to the right, as indicated by the blue arrow. I've also attached the impostor's normal map used in the screenshots. vegetation_juniperoxy_large_impostor_n.rar

Weve put quite a lot of effort into creating some billboards, that 1) Scale automatically so they are always the same pixel size on screen 2) Automatically adjust offsets to keep the billboards where we need them in relation to a real world object. 3) Use of materials to allow us to fade these billboards in and out This has already been quite a lot of work, that you feel there must be an easier way of doing this. We just want a label (admittedly quite a fancy graphic label) to hover over an object at a fixed size that can be faded in and out any suggestions on a better way of doing this. Our latest problem is the billboards are (quite rightly) being obscured by other real world objects, which we dont want. These labels need to be 'on top' If we have to continue with the billboard approach, is there a way we can stop a billboard being obscured by other world objects?

Is there any way of controlling how small / large a billboard ( or any other object really) grows/shrinks to. Ideally i want a billboard placed in the world that doesnt change size, no matter how far from the object you are.