Talk:Skybox (2D) with Terragen
Terragen, is not freeware, and making a sky 960 and then resize it to 1024, is not good at all. /hipshot
- "Terragen is free for personal non-commercial use." —Ts2do 19:12, 16 Sep 2005 (PDT)
- Of course, but you cannot use all functions if you don't have the full version, then its no longer freeware. And that is why he suggest using 960^2 instead of directly 1024^2 since the latter is not possible in the trial version. And as I see it, its better creating 512^2 skies with terragen if you can't make 1024^2 skies. All Valves skies are 512^2 and they work good. --Hipshot 05:27, 17 Sep 2005 (PDT)
- Ok, now I changed the resolution from 960 til 512 and 2048 til 1024. Also, I removed the section about sizing up 960^2 textures to 1024. Its not good to rezise a texture upwards, the added information when sizing up a texture just makes it worse quality vise. Making a envmap 2048 with terragen is not recomended, the huge size is insane to render if you want maximum quality also, times six, since you need six textures to make a env map. The quality of terragen skies in high resolution can also be debated since its current cloud rendering, which is kinda bad. Six material textures, at 2048^2 would use a insane amouth of memory compared to 1024^2 and not to say 512^2.
- A bilinear upscale from 960px to 1024px isn't going to noticeably degrade the quality of a Source-style skybox, as Source-style skyboxes are naturally soft (this is for a pseudo-DoF effect; any sharp details should be sky_camera miniatures). I concur that 2K skies probably aren't worth it for this reason (even on a 4K monitor), but I'd still argue that 1K skies make sense, especially when using compression (as you should usually be doing). While all of Valve's skies may have been 512px 17 years ago, 1024px skies are now much more common.
The main problem is that upscaling from 960px to 1024px without accounting for the wrapping between the textures will cause sharp seams on the borders of each face.The easiest way to account for this would be a convoluted process of converting to a cylindrical projection, tiling the image before upscaling, cropping after upscaling, and then converting back to box projection using SkyPaint. That is way too much effort for the average user to understand, so I'd recommend just sticking with 512px and not compressing the skyboxes (to avoid the artefacts/color banding that are more noticeable at the sub-HD resolution).
— SirYodaJedi (talk) 09:54, 13 October 2022 (PDT)- Update from the future: don't do it the way I mentioned; that will result in distortion on the top and bottom faces. I was able to successfully upscale dmcp from 256px to 1024px using an even more convoluted method involving fitting the images together in
and tiling and stuff, but I only did that because 
source ports don't have a way to designate skyboxes as always filtered regardless of gl_texturemodelike they are in
; if you are making a skybox from scratch, don't have resolution constraints, and have texture filtering on, then 512 is plenty (if texture filtering isn't on, then 1024 is plenty).
— SirYodaJedi (talk) 15:06, 12 December 2023 (PST)
- Update from the future: don't do it the way I mentioned; that will result in distortion on the top and bottom faces. I was able to successfully upscale dmcp from 256px to 1024px using an even more convoluted method involving fitting the images together in
- A bilinear upscale from 960px to 1024px isn't going to noticeably degrade the quality of a Source-style skybox, as Source-style skyboxes are naturally soft (this is for a pseudo-DoF effect; any sharp details should be sky_camera miniatures). I concur that 2K skies probably aren't worth it for this reason (even on a 4K monitor), but I'd still argue that 1K skies make sense, especially when using compression (as you should usually be doing). While all of Valve's skies may have been 512px 17 years ago, 1024px skies are now much more common.
- Ok, now I changed the resolution from 960 til 512 and 2048 til 1024. Also, I removed the section about sizing up 960^2 textures to 1024. Its not good to rezise a texture upwards, the added information when sizing up a texture just makes it worse quality vise. Making a envmap 2048 with terragen is not recomended, the huge size is insane to render if you want maximum quality also, times six, since you need six textures to make a env map. The quality of terragen skies in high resolution can also be debated since its current cloud rendering, which is kinda bad. Six material textures, at 2048^2 would use a insane amouth of memory compared to 1024^2 and not to say 512^2.
- Of course, but you cannot use all functions if you don't have the full version, then its no longer freeware. And that is why he suggest using 960^2 instead of directly 1024^2 since the latter is not possible in the trial version. And as I see it, its better creating 512^2 skies with terragen if you can't make 1024^2 skies. All Valves skies are 512^2 and they work good. --Hipshot 05:27, 17 Sep 2005 (PDT)
Correct Terragen 2 camera angles
I've noticed that (at-least when using TG2) the camera angle aren't correct; they need to be offset. Here's the proper angles:
0 270 0 Front 0 0 0 Left 0 90 0 Back 0 180 0 Right 0 0 90 up 0 0 -90 Down
This will make it so when the Sun's heading is '0', the light_environment should also be "-[height] 0 0" I don't know why this is, or maybe I'm wrong; but it seems to work properly so I can copy directly from TG2 into source and the sun will aim correctly. --Glitchvid 02:02, 27 October 2013 (PDT)
