Disclaimer:
If any or more of these points are already being processed by the heroes of ProRender, please dismiss it.
This list isn't built in any order; it's just which feature pops into my mind first. Sorry about that. Already got so many ideas to improve this great render even more!
Shader Editor
- Set the Uber node to 'IOR' as default instead of 'Metalness' since most materials are Dielectric. I'm also curious why ProRender uses a default value of 1.5 while Cycles uses a value of 1.45. Which one is better?
- Create a Layer Shader so multiple textures / colors can be stacked on top of each other (each with its own Blending Mode) instead of having to connect multiple Mix RGB nodes after one another. Make it look more like Photoshop.
I attached a simple concept image. I think I have seen this in C4DtoA. - Enable Box Mapping. Just a slider and a 'blend' works great.
- Enable Triplanar Mapping for the more experienced user who needs more options than just Box Mapping.
- Add more Noises. Cinema 4D has got about 20 different ones. Make them animatable (is that even a word?).
- Enable Node Wrangler so I can use the familiar shortcuts to see a preview of just a texture instead of the whole RPR Uber node. And many, many other options (please read this in the voice of Commandant Lassard).
- Create a Material Override option.
- Create a working Gradient texture. Change the Roughness of materials to a more physically accurate one like this example: 1 Tip to INSTANTLY BETTER Materials - Blender 2.8 Tutorial (Eevee & Cycles) - YouTube
- Create a working Hue/Saturation node.
- Create a working Displacement node. Think about adding it back into the RPR Uber node as an option instead of having to add an extra node for it. Combine. (I think it might have been combined with the RPR Uber node before). Please enable support for TIFF files.
- Make a Texture Image node which picks 'sRGB' or 'Non-color Data' by itself. It's really annoying to have to pick this for every. single. texture. always. I never needed to do this in Cinema 4D, only in Blender.
- Fix the Backscatter option. The manual says I have to increase the Backscatter Weight in order to get more Backscatter (which is just Translucency, right?), but while doing so my object just gets darker.
- Let users only pick Shaders / Nodes that are compatible with the RPR Uber node. It gets really confusing otherwise.
- I know it's currently not possible due to restrictions in Blender, but please change the layout of the RPR Uber node. Currently all inputs are separated from the options. For example: when I find 'Emission' in the list and enable it, its inputs are shown somewhere at the bottom of the RPR Uber node, which forces me to search for them again. Please make them show up next to the 'Emission' button so it's less clouded. I have attached a file which explains this. I know it's currently not possible, but maybe in the future?
- Is it possible to use colors for each option in the RPR Uber node? I mean, when I have enabled a few shaders, I see many, many options which all look alike ('Diffuse Weight', 'Reflection Weight', 'Refraction Weight'). For example, make all 'Diffuse' options a bit reddish, all 'Reflection' options a bit blueish and all 'Refraction' options a bit greenish. Just to separate them a bit more which makes it easier for users to see in which category they are plugging their texture into. Use dividers if needed.
- Create a Cycles-to-ProRender-material-converter. Make it so that no nodes will go lost in the process, so users can start rendering immediately instead of manually having to go through each one.
Rendering
- Create a Cryptomatte pass.
- Create a Render Log which afterwards shows what percentage of the render time was used for each object. This enables users to improve some heavy objects in order to improve render speed. Never seen this option in other renderers, so ProRender might be the first to support this
- Create a Look Dev mode so I can quickly see what a Noise (or other texture) looks like instead of having to render every time I change a value.
- Enable the embedded addon 'Auto Tile Size' so I don't have to test all possible tile sizes in order to get the right ones.
- Simplify / explain the RPR Denoiser. It probably works great, but I have no idea which one to pick for each render. Is it possible to build just two with easy names like 'Still denoiser' and 'Animation denoiser'? That way even a n00b user can't go wrong.
I'll be on holiday for a week so I won't be able to answer any questions for a while, I'm sorry.
I'm not whining about any missing features or bugs - I love ProRender and just want to help improve it even more. This is the best renderer I have ever seen! Fast rendering Motion Blur and Depth of Field - amazing. My iMac finally comes to live! Thank you so much guys!
Hey thanks! Lots of stuff there.
Let me reply with thoughts:
Shader Editor
- Set the Uber node to 'IOR' as default instead of 'Metalness' since most materials are Dielectric. I'm also curious why ProRender uses a default value of 1.5 while Cycles uses a value of 1.45. Which one is better?
This seems like opinion.... some prefer metalness some IOR. We choose metalness to match principled
- Create a Layer Shader so multiple textures / colors can be stacked on top of each other (each with its own Blending Mode) instead of having to connect multiple Mix RGB nodes after one another. Make it look more like Photoshop. I attached a simple concept image. I think I have seen this in C4DtoA
Coming soon!
- Enable Box Mapping. Just a slider and a 'blend' works great.
- Enable Triplanar Mapping for the more experienced user who needs more options than just Box Mapping.
These aren't highest priority tbh. But we will get around to fixing
- Add more Noises. Cinema 4D has got about 20 different ones. Make them animatable (is that even a word?).
We are working something in a few months that will expand shader system massively. Stay tuned.
- Enable Node Wrangler so I can use the familiar shortcuts to see a preview of just a texture instead of the whole RPR Uber node. And many, many other options (please read this in the voice of Commandant Lassard).
I'm not sure what exactly we can do here. I think the thing is that Node Wrangler is hard coded for certain nodes. I'll look into the preview texture part.
- Create a Material Override option.
Do you have an example of this?
- Create a working Gradient texture. Change the Roughness of materials to a more physically accurate one like this example: 1 Tip to INSTANTLY BETTER Materials - Blender 2.8 Tutorial (Eevee & Cycles) - YouTube
The ramp node works. Is that what you're asking for.
- Create a working Hue/Saturation node.
On our list
- Create a working Displacement node. Think about adding it back into the RPR Uber node as an option instead of having to add an extra node for it. Combine. (I think it might have been combined with the RPR Uber node before). Please enable support for TIFF files.
It doesn't really make sense to have in the shader node. As a separate material input makes more sense here. We did some work to make this work similar to cycles recently. See the displacement thread
- Make a Texture Image node which picks 'sRGB' or 'Non-color Data' by itself. It's really annoying to have to pick this for every. single. texture. always. I never needed to do this in Cinema 4D, only in Blender.
This is easier said than done. As much as Andrew "blederguru" likes to harp on it . For example what if your texture node links to two different inputs, one that needs sRGB and not? What if you want to override. We'd rather follow the Blender convention here.
- Fix the Backscatter option. The manual says I have to increase the Backscatter Weight in order to get more Backscatter (which is just Translucency, right?), but while doing so my object just gets darker.
Can you provide an example? Don't want to guess at your shader setup.
- Let users only pick Shaders / Nodes that are compatible with the RPR Uber node. It gets really confusing otherwise.
What do you mean? Any nodes that are in the menu should work with uber.
- I know it's currently not possible due to restrictions in Blender, but please change the layout of the RPR Uber node. Currently all inputs are separated from the options. For example: when I find 'Emission' in the list and enable it, its inputs are shown somewhere at the bottom of the RPR Uber node, which forces me to search for them again. Please make them show up next to the 'Emission' button so it's less clouded. I have attached a file which explains this. I know it's currently not possible, but maybe in the future?
Ummm.... so you want something that you know is not possible in the Blender UI? Either way I'm involved in blender dev discussions. I'd agree a better solution in Blender would benefit all.
- Is it possible to use colors for each option in the RPR Uber node? I mean, when I have enabled a few shaders, I see many, many options which all look alike ('Diffuse Weight', 'Reflection Weight', 'Refraction Weight'). For example, make all 'Diffuse' options a bit reddish, all 'Reflection' options a bit blueish and all 'Refraction' options a bit greenish. Just to separate them a bit more which makes it easier for users to see in which category they are plugging their texture into. Use dividers if needed.
Hmm, let me look into that. Again with the above we can't change the blender UI limitations but maybe something can be done.
- Create a Cycles-to-ProRender-material-converter. Make it so that no nodes will go lost in the process, so users can start rendering immediately instead of manually having to go through each one.
Right now we're focused on converting nodes automatically from blender. We're making that dramatically better in coming months.
Rendering
- Create a Cryptomatte pass.
On roadmap
- Create a Render Log which afterwards shows what percentage of the render time was used for each object. This enables users to improve some heavy objects in order to improve render speed. Never seen this option in other renderers, so ProRender might be the first to support this
RenderMan has something similar (I should know, I wrote this: Diagnostics ) It would be nice to do something like this.
- Create a Look Dev mode so I can quickly see what a Noise (or other texture) looks like instead of having to render every time I change a value.
How do you think this should be exposed
- Enable the embedded addon 'Auto Tile Size' so I don't have to test all possible tile sizes in order to get the right ones.
You don't have to set a tile size in RPR unless you're doing the tiled option. The sizes shouldn't make a huge difference in RPR.
- Simplify / explain the RPR Denoiser. It probably works great, but I have no idea which one to pick for each render. Is it possible to build just two with easy names like 'Still denoiser' and 'Animation denoiser'? That way even a n00b user can't go wrong.
Basically use the AI denoiser. Always
Shader Editor
- Set the Uber node to 'IOR' as default instead of 'Metalness' since most materials are Dielectric. I'm also curious why ProRender uses a default value of 1.5 while Cycles uses a value of 1.45. Which one is better?
This seems like opinion.... some prefer metalness some IOR. We choose metalness to match principled
True, it's probably just an opinion. But when I look at Principled BSDF, I see both 'Metalness' and 'IOR'. It seems to be possible to use them in combination, instead of forcing users to choose between them. And as far as I know, the global amount of used metal shaders in scenes is much lower than dielectric shaders. Hence my suggestion to use 'IOR' as default value instead, or to make a combination of both 'Metalness' and 'IOR' (like Principled BSDF as you suggested).
- Enable Box Mapping. Just a slider and a 'blend' works great.
- Enable Triplanar Mapping for the more experienced user who needs more options than just Box Mapping.
These aren't highest priority tbh. But we will get around to fixing
Ah, that's a pity. These options save everyone so much time as we (almost) don't need to UV unwrap anything anymore (which takes too much time). If I'm right, you said somewhere that integrating Displacement currently has a bigger priority. I would disagree. Displacement is only rarely used in scenes for a few objects where Normal Maps are not enough to create realism, while Box Mapping is continuously used for many, many of objects in our scenes to save lots of time.
- Create a Material Override option.
Do you have an example of this?
Yes, please open Blender, go to menu 'Properties > View Layer > Override'. There you can pick any Material to temporarily override all used Materials in a scene. This can be handy when you e.g. only need to render a Mask ID pass (in case you forgot to check it the first time) and saves lots of render time as the Material is really just a white Emission shader. Currently I have to replace every 
Material by hand to achieve this.
- Create a working Gradient texture. Change the Roughness of materials to a more physically accurate one like this example: 1 Tip to INSTANTLY BETTER Materials - Blender 2.8 Tutorial (Eevee & Cycles) - YouTube
The ramp node works. Is that what you're asking for.
Sorry, but it doesn't. Not really. Just try to give the cube a vertical Gradient. The current Gradient node only rotates around the Z axis. Or am I missing an RPR update?
- Make a Texture Image node which picks 'sRGB' or 'Non-color Data' by itself. It's really annoying to have to pick this for every. single. texture. always. I never needed to do this in Cinema 4D, only in Blender.
This is easier said than done. As much as Andrew "blederguru" likes to harp on it . For example what if your texture node links to two different inputs, one that needs sRGB and not? What if you want to override. We'd rather follow the Blender convention here.
Just curious: how does Cinema 4D achieve this then? I never had to pick anything using C4D.....
- When a user has set his scene to use Prorender, please make it so that every new Material automatically uses a RPR Uber shader instead of the Principled BSDF shader. Now I have to manually change this for EVERY Material I make in Prorender.
- When building a Layer Shader, please add the good ol' "Levr" Blending Mode from Cinema 4D. This saves so much time when creating a design. (http://www.peranders.com/tutorials/tutorials.php?index=5, search for 'levr')
- Let's please try to decrease the amount of nodes needed to build a proper Material even more (hence the request for a Layer shader) and add an 'Invert' slider to the Image Texture node. Add this basic option to all other Color-like nodes and ditch the then redundant Invert node.
Rendering
- Create a Look Dev mode so I can quickly see what a Noise (or other texture) looks like instead of having to render every time I change a value.
How do you think this should be exposed
I'm not sure what you mean by 'exposed'. Is it possible to use Cycles' Look Dev mode as Look Dev mode for RPR as well since it just enables users to instantly see their changes?
- Enable the embedded addon 'Auto Tile Size' so I don't have to test all possible tile sizes in order to get the right ones.
You don't have to set a tile size in RPR unless you're doing the tiled option. The sizes shouldn't make a huge difference in RPR.
As a matter of fact, it actually does make a huge difference. It saved me lots of time to set the Tiles to 2048 instead of 16 (as I used to do while CPU rendering).
- Simplify / explain the RPR Denoiser. It probably works great, but I have no idea which one to pick for each render. Is it possible to build just two with easy names like 'Still denoiser' and 'Animation denoiser'? That way even a n00b user can't go wrong.
Basically use the AI denoiser. Always
Can you show me how to accomplish this? I only see four Filter Types in menu 'Properties > View Layer > RPR Denoiser':
1. Bilateral
2. Local Weighted Regression
3. Edge Avoiding Wavelets
4. Machine Learning
Which one of them is the 'AI denoiser'?
Many thanks for your patience to comment on my list. I love RPR and hope to be able to contribute.
Thank you for your reply, Brian!
Shader Editor
1. View layer override. That should be doable.
Don't know if that's the same thing as Material Override, but I guess you know what I mean
2. Gradiant. Can you attach a scene of what you're doing?
Haha I'm pretty new to this community, so I don't know how to attach scenes to this message.
It's actually pretty simple though:
***Just try to give the default cube a vertical Gradient (top to bottom).***
You'll see that the current Gradient node only rotates around the Z axis. Please fix this error since the Gradient node is pretty useless now.
3. Global switch to make new materials Uber. I think we can do that too. Also we added an "Upgrade principled to Uber" button in the material properties.
I actually meant this feature to be default in RPR, not to be a switch. Since you guys from ProRender built the Uber node to be better than the Principled BSDF node, I thought you'd make the Uber node default when a user has switched to ProRender in their scene.
4. How come I never had to pick 'sRGB' or 'Non-color Data' in Cinema 4D or any other 3D program? Why does only Blender appear to need this for every texture? Just curious
5. When building a Layer Shader, please add the good ol' "Levr" Blending Mode from Cinema 4D. This saves so much time when creating a design. (http://www.peranders.com/tutorials/tutorials.php?index=5, search for 'levr') See the levr.gif file I attached.
6. Let's please try to decrease the amount of nodes needed to build a proper Material even more (hence the request for a Layer shader) and add an 'Invert' slider to the Image Texture node. Add this basic option to all other Color-like nodes and ditch the then redundant Invert node.
7. Is it possible to create a Bevel node like the one in Cycles? This also saves a lot of time since I don't have to really make Bevels for every object.
Rendering
1. Create a Look Dev mode so I can quickly see what a Noise (or other texture) looks like. Look Dev works so much faster after each little value tweak than having to render everything with Rendered Mode.
2. Enable the embedded addon 'Auto Tile Size' so I don't have to test all possible tile sizes in order to get the right ones. Rendering with the right Tile Size really makes a huge difference in render times!
3. Good point by Kurt Wilson: please make rendering with a transparent background possible.
Thanks again, have a great weekend!
PS: although I deleted the whole 'Box / Triplanar Mapping' discussion, this still has top priority for me and other users. Would be great if you could build it to save us plenty of time!!!
Errrr that's a bit too technical for me I gues 
It's just that I can't rotate the gradient the way I'm used to in Cycles, that's all.
I have recently updated my list. Would you mind taking a look at it (and responding) again?
O that's great! Thank you so much!
I can imagine that not all points in my list are clear to you.
Are there any more points in the list that I can make a test file for to explain it better?
It's no problem for me if that helps you making RPR even better!
