Hello, I’m currently working on a Skydome for Portfolio renders and I want to have a Platform which only reflects the model and makes the rest transparent. It also shouldn’t reflect the World/Background.
I also have a reference from Genshin Impacts Handbook:
Thanks in advance!!
I do not understand what you mean by this two things:
Do you want this like glass and show something below ?? Also if the is reflective then it will reflect the background… so you have 1. reflection of and BG 2. no BG at all 3. BG behind non-BG reflection
Okay so I want to only let the object reflect on the surface and the rest is fully transparent so you can see what’s below the platform.
So… then make your platform more transparent… here setting the Alpha value of my used Principled Shader to 0.4… (the green suzanne is under the platform) or use a Glass shader… or use a any Mix Shader and a Transparent BSDF :
I think I have a way. It involves altering the background material so it shows differently in reflections and refractions compared with looking at it directly.
You can see here that the glowing objects reflect on the plane, the blue slab is visible through it, but the background doesn’t reflect and isn’t visible through it.
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Here is what you do in the world shader:
In this setup, the bottom background node represents what you will see if you look at the background directly (you can plug your HDRI in it). The top background node is what will be visible in reflections and refractions (you can give it a flat color that’s close to your HDRI).
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The ground material needs to use Eevee’s raytraced refractions for its transparency for this trick to work.
The transparency needs to be done with transmission, not alpha.
The roughness should be set to 0 so the reflection is as sharp as possible. Unless you are looking for a blurry reflection, then this is the place to do it.
The render method needs to be dithered so the reflections and refractions work (this will be a bit noisy, so you might need to increase the render samples).
Raytraced transmission needs to be active. You will also need to activate raytracing in the render settings (looks like you already did from your image).
The thickness should be set to slab mode, as we are dealing with a flat platform, and a small thickness value is set in the material (so it refracts like a thin glass pane and not like a solid mass of glass).
The IOR will affect the look of the reflection and transparency.
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In the render settings, there are a few changes that should be made for the reflections to look as nice as possible.
The resolution is set to 1:1, the precision to 1 and the denoising is deactivated. These options should give you the clearest reflections. You could use denoising if you want a faster render, though I would disable the “temporal accumulation” setting, it can degrade lighting quality quite a bit.
Because we are using dithered reflections on the material, the render is going to need a decently high number of samples anyway (128 seems fine with denoising), so you might as well disable fast GI and get the best raytracing quality, as you will have enough samples for it anyway.
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Finally, I have used a reflection plane light probe to get the best quality reflections. A flat surface like this is the perfect use of it.
Here is the file.
plane_reflections.blend (747.8 KB)
