Greetings Planetsiders,As I joined the Terragang 3 days ago I am glad to find a community that commited which pushed me to invest myself into Terragen. However the learning curve is steep and I have many questions, for now only regarding animation, cloud shaping, cloud distribution, render layers and general render issues. Feel free to bring your input on whatever point nor general idea about where I might be wrong, right and how you would do it. As time will go on I will update all my progress here.
My project : I chose Terragen for it's realistic volumetrics rendering. I have to create a scenery for a 1920*1080p animation (30sec faked sequence-shot) taking place in the sky. I only need clouds as you never see the ground. It takes place in a summer blue sky, the sun is still, high noon. Around 10 models are filmed on a green screen. One by one they are supposed to pose laying on photorealistic puffy clouds. As the camera travels, goes up, down and pan between the different characters, almost no camera rotations are involved. Also, I have transitions allowing me to cut seamlessly from one scene to another by passing through a cloud.
My Modus Operandi: • I create my early scene in Blender so I can export my cameras animation as an .FBX to Terragen 4 Pro.
• I import preview images cards attached to Null Objects also set in Blender to preview where my models are supposed to be during my animation.
• Both my camera and my models are oversized (let's say here a human is around 100meters tall) so the clouds they are laying on have the same level of details that the one you can see from your window. It also allows to have small details in clouds shapes, main features and animation (the size of evolution noise for example).
• I create multiple Cloud Layers within my atmosphere answering different purposes:
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Background clouds field: to have a coherent background during the whole clip
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Middleground clouds field: to have some kind of parralax effect over the background clouds field during the whole clip ( I need to use a distance shader to avoid those clouds to appear to close to the camera)
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Principal clouds: which are multiple individual clouds layers grouped together, shaped and placed one by one as some clouds need to be located at specific areas (ex: where a character is sitting). I also might have to create additional cloud cards splitting some of those clouds in two to have some of the cloud passing in front of a character (ex: in front of a hand or the hips as they are sitting, maybe I can skip the cards here and create some animated cloud alpha masks to apply on a characters mask in AE)
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Foreground clouds: to enhance the depth of the scene by bringing a discrete foreground cloud card between the models and the camera
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Transition clouds: those are individual clouds shaped and placed one by one as some need to be located at specific areas. As the camera needs to dives in and out from them I will render them as cloud cards.
• I render each Cloud Layer separately with Pixelplow in 360p, standard renderer, 2d motion blur with low Anti Aliasing (2), low GI settings (Prepass at 2,2,X / GI in cloud quality at Sequence Quality x1 / Voxel Scattering Quality at 100) optimized with 10 millions of voxels, each of them is rendered in .EXR with a Render Layer Element and extra output images Cloud Alpha, Cloud RGB and Cloud Depth in .EXR. Then I assemble them in After Effect for previewing and early compositing.
• After that I finetune short sequences (30frames) on key moments in higher resolution (720p), standard renderer, 3d motion blur with higher AA (4), higher GI settings (prepass at 2,2,X / GI in cloud quality at Sequence Quality x2 / Voxel Scattering Quality at 300) and optimized with 10 millions of voxels.
• If the previous settings suits me I render each Cloud Layer separately with a 1080p resolution, standard renderer, 3d motion blur, higher AA (6) or higher GI settings (prepass at 4,4,X / GI in cloud quality at Sequence Quality x8 / Voxel Scattering Quality at 300) and optimized with 30 millions of voxels.
My interrogations:1 - Render separated groups of Clouds with Render Layer group: AnsweredI create a dedicated group to render each layer of clouds separately from another within my scene. However, the Easy Cloud 01 located into the Object Group 01 rendered into visible with all other objects set to invisible creates a black image both on the RTP and render, unless I plug it directly into the Platnet 01 athmosphere shader and add the Planet 01 into the Object group. Is there a dedicated process to render only a specific Cloud Layer without disconnecting all the other from the node tree nor duplicating a Planet in each render group?
Edit:
Kevin Kipper's input: Cloud layers can not be isolated by using the Render Layer's OBJECT groups. They are two different types of items. To isolate a Cloud Layer you need to render separate passes, or add new planet objects to your project and create a Cloud Layer within its internal node network. You can disable the Planet from rendering as needed. Group the planet to itself and add it to the Render Layers group.
2 - Not that flat belly cloud: AnsweredAs I will explore through the nodes to sculpt better clouds I am curious to know if parameters exist to quickly create clouds with a not that flat belly and more rounded shape on their bases.
Edit:
Kevin Kipper's input: For cloud sculpting please refer to the online Wiki documentation for cloud layers, specifically the Cloud Profile settings here:
https://planetside.co.uk/wiki/index.php?title=Cloud_Layer_v3#Tweaks_Tab3 - Saw in HQ renders: flickering shadows: While rendering my previews, I know I shouldn't aim for lowest settings possible but rather for something coherent with the final result I expect. However, if i dont have noise at high resolution and settings tests, I have issues with light flickering through the belly of clouds (similar to a thunderlike effect) when rendering an animated cloud (slow drift + evolution) in 1080p, standard renderer, micropoly details at 0.5, AA 8, prepass 4,2,8 / automatic GI cache / GI in Clouds at Sequence Quality x4, max ray depth 2, Quality: rendering method 3D(volumetric), smallest scale at 0.1 and Optimisation: voxel scattering quality at 200 with 30m voxels and acceleration cache set to none. As I am writing that I just read that Oshyan suggests a GI Blur Radius between 300-500 and Richard Fraser recommands to go around 800.
4 - Cloud Cards and reverse cloud cards: AnsweredAs you create cloud cards for close cloud details nor animations (ex: my foreground clouds or my transition clouds), what is the opposite way to avoid clouds from a dedicated layer to appear too close to the camera? Is it by using some kind of Boolean set to difference and attached to your camera or by going into render layer/layer settings/near clipping distance and keyframe here depending of the needs? Maybe even a reverse cloud card setting somewhere?
Edit:
WAS's input: The distance shader allows you to attach a camera, and use it's scalar gradient from 0-1 to mask out clouds close, or far away from the camera. This will work with an animated camera, as well. Documentation here:
https://www.planetside.co.uk/wiki/index.php/Distance_Shader5 - Render farm and GI cache:Rendering on Pixelplow means automatic GI cache file and no blendmode for animation. Is it better to submit them a file prepared to bake only GI settings (meaning I only check write to GI cache file, set a folder then send them my .TGD), then gather them into an updated file to resend it with an interpolated blend mode set to X?
6 - Rendering optimisation for an animation containing only clouds:There are no magical settings that makes a render looks good we agree on that. However here I only need to focus on an animation featuring clouds in 1080p with the less noise possible and rid of flickering. Feel free to share configurations that would look optimized for you as I will do the same while progressing through my project.
7 - Essential extra output images for compositing in Blender / After Effects:Going through Pixelplow allows you to also create extra output images, for now I can only think to use Cloud RGB, Cloud Alpha, Cloud Depth.
As I will continue to go through the wiki, explore more the forum and consider each one of your inputs I will update every steps and progress I make here posting .TGD, stills and clips. I hope it will create an interesting case about using Planetside's amazing volumetrics for VFX and compositing.
In the meantime I wish you all the best and I thank you all in advance. Take care! Sincerely, MC.