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Ray Tracing with POV-Ray: 25 scenes in 25 days (2013)

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Re: Ray Tracing with POV-Ray: 25 scenes in 25 days (2013)

#61

Post by TylerE »

BubRoss wrote: post #57
TylerE wrote: post #49

Earlier quoted context omitted.

POV-Ray disagrees. It renders CSG . It never converts to polygons. So stop saying what a 30 year old program does is "impossible".

I didn't say it was impossible, I'm talking about why these other geometry types aren't typically used instead of polygons. I asked 'how do you trace rays against it' because to do it directly is not fast, yet you are left with all the problems I stated that you skipped over. Think about what it would take to directly trace lots of overlapping primitives. What you gain from tracing it directly is minimal and what you…

Look at the POV-Ray source code. It does it. Again, I am literally telling you how the software under discussion works. and you keep insisting it is not so. It's open source!

Re: Ray Tracing with POV-Ray: 25 scenes in 25 days (2013)

#62

Post by DanBC »

ur-whale wrote: post #60

This has not aged well. Modern OpenSource renders like e.g. luxcorerender produce way more realistic images: https://luxcorerender.org/gallery/

I'm not sure it's fair to compare a gallery of images created while learning the software with a gallery of images created by people who are very familiar with their software.

Re: Ray Tracing with POV-Ray: 25 scenes in 25 days (2013)

#63

Post by holoduke »

CrLf wrote: post #50
klodolph wrote: post #33

I loved POV-Ray in the 1990s and early 2000s. The thing is—it’s ridiculous to try and make something remotely complicated or organic with POV-Ray, unless you are using some modeling program that can export to POV-Ray format. POV-Ray scenes were dominated by procedural textures and geometric primitives, for the most part. The rendering engine was very strong, and supported all sorts of features like area lighting, dep…

POV-Ray was my introduction to programming, before actual programming. Graph paper and a lot of trial and error. My longest render was 50 hours for a single 640x480 image, with caustics and area lighting. 50 hours of a Pentium 100 MHz buzzing near my bed.

How long would it take now on a modern machine? :) 5 , 10min?

Re: Ray Tracing with POV-Ray: 25 scenes in 25 days (2013)

#64

Post by holoduke »

anthk wrote: post #25
TylerE wrote: post #16

Earlier quoted context omitted.

> It features a lot of effects (radiosity, HDR maps, etc.) which are added on top of its basic functionality Huh? POV-Ray has supported radiosity for literally decades, since sometime around 1995.

Yep, I'm tired of these kids saying PovRay coudn't do shit as if PovRay had in 1997 the same capabilities of an Irix machine from 1987. They couldn't even be more wrong with that. I remember seeing photoreallistic images made with PovRay in 1997 you coudn't even do with a GPU today in real time. Kids today have a lot of ignorance on the 90's technologies, guess why they confuse the 80's and the 90's a lot thanks to t…

You are right, but the same can be said between 85 and 95. The evolution of realtime 3d graphics was insane. From some low FPS 3d line engines to full blown textured 3d engines.

Re: Ray Tracing with POV-Ray: 25 scenes in 25 days (2013)

#65

Post by TylerE »

CyberDildonics wrote: post #58
TylerE wrote: post #8

Earlier quoted context omitted.

That’s the beauty of CSG though... it’s volumetric, not surface based

How would that make it easier to work with?

You can do things like take shape A and then subtract shape B from it and all works, no matter how complex the intersection.

Re: Ray Tracing with POV-Ray: 25 scenes in 25 days (2013)

#66

Post by holoduke »

morsch wrote: post #40
anthk wrote: post #25

Earlier quoted context omitted.

Yep, I'm tired of these kids saying PovRay coudn't do shit as if PovRay had in 1997 the same capabilities of an Irix machine from 1987. They couldn't even be more wrong with that. I remember seeing photoreallistic images made with PovRay in 1997 you coudn't even do with a GPU today in real time. Kids today have a lot of ignorance on the 90's technologies, guess why they confuse the 80's and the 90's a lot thanks to t…

> From 30Mhz and 5 1/4 floppies to ~450/600 MHZ a bunch of GB in 1999. From rare instances of people accessing their local BBS at 9600 Baud to accessing a worldwide communications network as a matter of course, often at broadband speed. The past 20 years really have been rather dull in comparison.

When you are inside a time or period not a lot of change is felt, but once you look back you can see incredible changes. You mention that last 20 years are dull. I think that the last 10 years are the era of smart phone revolution. A pretty big thing. Certainly belongs in the top 50 most impactful inventions and adoptations in human history. In 200 years from now the late 00s will be seen as the start of global connectivity.

Re: Ray Tracing with POV-Ray: 25 scenes in 25 days (2013)

#68

Post by holoduke »

tlb wrote: post #30
klodolph wrote: post #29

Earlier quoted context omitted.

I think you may have missed what the parent comment was saying—that the polygons can be made smooth before render time. This is not a question of just faking it with normals. Instead, you can actually just work with a polygonal mesh and then post-process it to make it actually smooth. The classic technique for this is Catmull-Clark subdivision. If you think polygons on screen are offensive, you can just run the algor…

Yes, but then any edges that should have been sharp get rounded too.

You can apply the algorithm on a subset of vertices. Exclude all the sharp edges. An extra falloff algorithm can make it even better

Re: Ray Tracing with POV-Ray: 25 scenes in 25 days (2013)

#69

Post by W-Stool »

gorgoiler wrote: post #53
CrLf wrote: post #50

Earlier quoted context omitted.

POV-Ray was my introduction to programming, before actual programming. Graph paper and a lot of trial and error. My longest render was 50 hours for a single 640x480 image, with caustics and area lighting. 50 hours of a Pentium 100 MHz buzzing near my bed.

Pentium? Pentium! We were lucky to have half a 486 and even then it were powered by ferrets, wi’owt e’en DX floating point coprocessor to its name.

Monty Python voice: "You were lucky!"

Re: Ray Tracing with POV-Ray: 25 scenes in 25 days (2013)

#70

Post by holoduke »

dahart wrote: post #45
BubRoss wrote: post #7

Earlier quoted context omitted.

Polygons can be smoother and subdivided efficiently at render time without artifacts, which is how they are used now. Nurbs and other curved surface representations end up with huge problems pragmatically when it comes to tools, workflow, visualization, texture coordinates, keeping the surfaces together etc. The list is long. Polygons are very simple in all these areas and can be made smooth at render time so you get…

This seems like a strange way to frame it. Polygons aren’t what get subdivided. Subdivision surfaces & NURBS are what get subdivided, and those are routinely used in production and have tooling. Polygons by themselves don’t get any smoother or provide the advantages you’re talking about, nor do they solve all problems of workflow, tex coords, stitching, etc.

You can apply subdivision on any type of geometry. Even voxels. Tesselation is also a form of subdividing.
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