VEX VOP SHOPs!! RnD for a personal project..

Well I have been pretty occupied by a personal project I have decided to take up in Houdini from start to finish. Its also a quite daunting task for now.

I have few tricks up my sleeve for some aspects of this....HOWEVER I definitely DO need to collect lots more!

So I set out on a RnD expeditition....and I do, now, FULLY REALISE enormity of the task....(better now than later..hahaha)

Yet I have decided to go ahead with it irrespective of whatever comes flying at me....

Not only I need to try and create some shaders that I'll be using for Environment and stuff....but also try and GET the lighting right..And in all honesty I say I have to improve my senses when it comes to Lighting.

Here's a test render of a cracked surface using a relatively low Poly Grid and my own Displacement Shader. It was only after I rendered this, that I realised that its pretty low on contrast and is not pretty crisp.

I tried PBR in Mantra, Global Illumination as well as some Ambient Occlusion..

& faced an issue with PBR though..

1) PBR did not really work for me because (I guess) it did not like my shaders :D

So I did try to search through the Hel dodcumentation but I need a way to incorporate PBR in

my shader for it to respond to it..

PBR is fundamentally a render engine which uses correct light simulations..So probably it will need some attributes to initiate things..

This certainly has been a challenging day...I hope get things right..and I'm running short on time!

EDIT: Though I mentioned the issue I faced with PBR (because of using my own shaders), It slipped my mind to also document its solution. I simply had to output my Lighting model's 'f' output to the Output's 'F' input....these are BSDF inputs which are needed for any ineraction with PBR (IMHO)..

thanks @danBode (at odforce) :)

Ambient Occlusion Baking..

Well this might not be the best way to demonstrate the workflow for baking occlusion or GI details on the geometry but will certainly get the point across.

As I mentioned in the earlier update of the Crater Project, I was trying to bake my Ambient Occlusion details onto the geometry.

Well I had finished a quick test for the same and thought of putting it up online.

Out of what I have been able to infer and conclude is probably pretty primitive..gotta look

up few other ways as well.

The workflow is pretty straight forward (only once you know how to go about it :) )

Make sure that you have UV attribute on geometry.

Create a light template and use a VEX Global Illumination as its light shader.

However the trickiest part is using the Mantra Command feature on the Mantra ROP.

The Mantra command for this is:

mantra -u /obj/name of object -b Float

This will render out just the baked Ambient Occlusion on the texture map which can then be used to fake Ambient Occlusion at almost real time.

The quality of baked Ambient Occlusion will depend upon the UVs. Make sure UVs are laid out properly. well you will see what would happen otherwise! Look at my baked image :(

Crater Project update #14--->Old Ghosts haunting newer efforts

Its been quite some time since the last update.

I had decided to take a break and experiment with some other stuffs like volumes and dynamics etc.

But what I had not thought of were my college assignments, which kinda sneaked in on me.

Anyways, here's the update for the crater project.

The contact shadows are still elusive. But I have not actually devoted much

time to those anyways. Most of my time has gone in trying to make shaders and texture the geometry appropriately. The crater feels like its been cut with a knife (or whatever manages to cut through the roads like butter).

Solution for this is? Well I have thought of using displacement maps to displace the geometry and make it look pretty uneven. I have even tried that out but somehow results have been far from what I had calculated. So I'm trying to understand the shader network for displacements by dissecting the built in ones.

Another solution to the same could be using a mountain SOP and trying to actually distort the model of the crater.

As for contact shadows, I want to bake the textures into the geometry (sans shaders) and then use a light template with a GI light shader to get an occlusion pass, which I could then use for the contact shadows. I also tried using takes to over-ride the materials or shaders applied to the geometry but there are around 10-12 shaders in the scene and I realised its really a cumbersome process to keep everything in one take (the concept is very comforting but cant say the same about the process)

So I tried baking the textures into the geometry using mantra command feature in the Mantra ROP and my machine FROZE....yea I it hung up my laptop. I have decided to give it more tries (probably after doing a bit more extensive RnD on the subject).

I'm pretty content with the lighting though..and believe whatever issues I feel are coming up due to lighting are actually because of *not up to the mark shading* done by me :)

Okie Dokie..enough for now.