12 hours ago, JoeJ said:

What i mean is that solving for forces in multibody constrained dynamics is a much harder problem, than testing for visibility in graphics.

This is like me saying that Art is a harder problem because it requires learning Anatomy rather than calculating Velocity. It's completely unbalanced.

Dynamics is a advance physics problem for computers, Like Anatomy is a advanced art problem.

12 hours ago, JoeJ said:

All of them try to do proper simulations based on correct equations of motion. This can't be faked in a way we can fake graphics by precalculated GI.

Of course they can and we do it all the time. Especially in racing games; some of them do use physics but most don't. Right now in my space game, I am faking DeltaV flight using Lerping; a trick I stole from a older game that used it to make a stable network game.

12 hours ago, JoeJ said:

Collision shapes are always accurate. Using a different representation for graphics does not make physics inaccurate, wrong or faked. Actually it's the graphics that is faked, if you want so.

It's not graphics if you can't see it. Making the collision boxes, pure physics. Unless you decide to make them visible to the player.

By the very nature of graphics, only physics that isn't visible, like the ray tracing of WOWS isn't graphics. Graphics Physics is a subgroup of physics just like Gameplay physics is a subgroup.

Look, I am not saying physics based games are bad or anything.

What I am saying is that we use more physics for graphics than we do for gameplay. Since you mentioned motion I will show you the formula used by animation players: 

It's Newton's second law. All animations in games follow this formula. All graphics elements in games uses physics.

If you think of physics as a resource, you will see we use it more for graphics than we do for gameplay. With actual game play mechanics depending on a lot less complicated formulas than rendering.

45 minutes ago, Scouting Ninja said:

Look, I am not saying physics based games are bad or anything.

You just mixing a terms "phisics simulation" and "phisic simulation engine component". It is not a same. Any games, excluding a card games,etc are phisic based.  Difference is it involve approaches that physic simulation engine have "from box" or  bring some other approaches only. Realy, game design is aprocess of adjustin a gaming engine universal abilities to concrete game concepts. Some approaches simulated by engine is independed from game concepts, otherwice it just not works. This part of approches adjusted by 100% data-driven way. But other approaches depends from game concepts, just becouse gaming phisics simulation is alweys compromise betwin accuracy, speed  and gameplay concepts. So engine developer just can not predict wich compromise have be selected for concrete game. So this part of features have be coded/designed at game development time.

For exammple let see to DooM's-like doors. Of course, it generally simulated by keyframe animation. But it still a phisic simulation, becouse animation have to match  position limits, movement direction and speed constraints. So for this usecase keyfame animation is not a replacemet of simulation, it is a precalculated optimization of simulation.

32 minutes ago, Scouting Ninja said:

Dynamics is a advance physics problem for computers, Like Anatomy is a advanced art problem.

Computers do not solve probelms. People solve problems using computers.

I've studied physics simulation, graphics, anatomy, all of them for much, much longer than 3-4 years now, and i can say physics is the hardest problem to solve mathematically.

This does not mean an artist that can draw anatomically correct images out of his head deserves less respect than the guy writing a physics engine. There is just no point to compare those very different skills. But writing a physics engine requires more skill in math than a game renderer for games, because the problems are much harder to solve. You would agree if you would be more skilled in physics yourself.

This does not mean physics guys ARE more skilled than graphics guys. I only talk about minimal requirements to pull off those things. Also there are difficult fieldes in CG as well, but i only talk about current state of the art in games.

50 minutes ago, Scouting Ninja said:

13 hours ago, JoeJ said:

All of them try to do proper simulations based on correct equations of motion. This can't be faked in a way we can fake graphics by precalculated GI.

Of course they can and we do it all the time. Especially in racing games; some of them do use physics but most don't. Right now in my space game, I am faking DeltaV flight using Lerping; a trick I stole from a older game that used it to make a stable network game.

If you make a simple racing game, yes you can do it without a need to solve anything. Also a typical space game does not have any physics problem to solve. You can just apply newtons laws to individual bodies. But that's as easy as rasterizing a circle. 

I talked about constrained multibody dynamics and made this clear. Try to write a simulator which can handle stacks of rigid bodies with different masses by calculating contact forces. Than you know what i mean. (And please now do not link to another paper from Erin Catto that proposes one way to get there just because everybody else links to them. And pleas no more laws of Newton - i've heard of them, no need you show me)

The rest of your post is not worth to be adressed. Again you place some unrelated facts everybody already knows in a trial to strengthen your own weak argumentation, and again you assume the way YOU perceive the process of making games is the way WE make games, which implies that ALL games are made in a way YOU think. In other words: You know it all.

I prefer the assumption that i know almost nothing - this is much closer to the truth, not only for me but for all of us 

7 hours ago, JoeJ said:

If you make a simple racing game, yes you can do it without a need to solve anything. Also a typical space game does not have any physics problem to solve. You can just apply newtons laws to individual bodies.

Anycase yo have to detect and habdle collisions. How to handle depend from how much accurate and relistic simulation required by game concepts. But collisions is key feature in both cases. Othervice it will be racing of relativic horces in spherical vacuum.

Really it could not be compared how much phisics uses rendering,  dynamics simulation or game mechanics. Its all are uses phisics but different branchs. So it can be compared how mach calculation Its require. Just game mechanic commonly uses approach that can be integrated analiticaly, so uses less processor instructions, synamic simulation uses approaches that have be integrated numericaly, so uses more processor instructions. 

4 hours ago, Fulcrum.013 said:

Really it could not be compared how much phisics uses rendering,  dynamics simulation or game mechanics. Its all are uses phisics but different branchs.

Agree, and as you already have pointed out, we can boil down pretty much everything to physics and finally math.

However, if we talk about physics in games, probably most of us think about rigid body simulation including stacks of boxes under gravity, joints for ragdolls, motors, etc. If you ask a gamer what physics in games means to him, he'll probably answer gravity gun in HL2, a game where the whole world is based on advanced physics simulation. 

So this is my personal definition of the term, and looking at the OP video the whole thread seems to follow this definition as well.

13 hours ago, Scouting Ninja said:

If you think of physics as a resource, you will see we use it more for graphics than we do for gameplay. 

This thread is not about the majority of games NOT utilizing worlds based on physics simulation. It is about the minority of games that do so. Clearly there is interest in massive particle / rigid body simulation involving resting contact. Somebody interested in this probably wants to use it for gameplay an not just eye candy, considering the high performance cost this takes and what you have to sacrifice.

Other things, e.g. ballistic or spaceship trajectories, precomputed door animations, PBR shading... all of this involves physics and has been discussed, but it is not only easy to implement in comparison to the above (no large problems with multiple unknowns), it is also off topic.

This is why an argument like 'WE use it more for graphics than we do for gameplay' does not hold here and is unrelated IMHO.

6 hours ago, JoeJ said:

but it is not only easy to implement in comparison to the above (no large problems with multiple unknowns)

Really ridgid bodys dynamic  is simple like as loop counter. Complexive is analitical geometry, that involved to computation of loop increment. Animated doors just have geometry conditions precomputed. Approximating body by stack of spherical particlles is just a way to simplify involved analitical geometry. Sphere-sphere and sphere - plane is simpliest of collision detection algos, also it crazzy efficient. It involves dot products only, that even CPU can compute each cycle per core. Also prediction of impacts for spheres is a simpliest of predictions algos, it is require just to find  a distance betwin 2 straight lines at 4D space only. 

Really, anything genious is simply. Complexive is to find how to done complex task by simple tools.

2 hours ago, Fulcrum.013 said:

Really, anything genious is simply. Complexive is to find how to done complex task by simple tools.

Great words

On 6/17/2018 at 10:37 PM, JoeJ said:

which implies that ALL games are made in a way YOU think.

First, I never meant to offend or to challenge your ideals. Second, I never said ALL, I said MOST.

On 6/17/2018 at 10:37 PM, JoeJ said:

You would agree if you would be more skilled in physics yourself.

Where words fail me actions don't. The game I am working on was delayed because of work, it will be done before the end of this year. I will send you a copy when done. You can judge for yourself what I can do. As I will be judging you by the games you make. Good luck

6 hours ago, Scouting Ninja said:

First, I never meant to offend or to challenge your ideals. Second, I never said ALL, I said MOST.

I think i already tried to adjust my point towards including the ratio given by the word 'most' in the next post. You always pick something i say out of context so it turns arguable, but you refuse to comment my arguments. I comment your points, you quote me just to introduce new points, becoming more and more unrelated. It seems the only reason you quote me at all is just to continue argumentation, instead just saying: maybe i was wrong about that tiny detail that was wrong.

13 hours ago, Fulcrum.013 said:

Really ridgid bodys dynamic  is simple like as loop counter.

To me it is not, it is an open research topic.

However, if you, somebody who is more involved in physics than myself i guess, says it is simple,

i realize my own statement 'physics is harder than graphics' is either too subjective ore just stupid.

I take it back, oops i was wrong and sorry.

But again, a statement like 'Physics can even be considered a graphics element most of the time, only there to make things look more realistic or dynamic.' IMHO is misplaced in a thread starting with a video about rigid body dynamics and downplays the application of this field.

6 hours ago, Scouting Ninja said:

Where words fail me actions don't. The game I am working on was delayed because of work, it will be done before the end of this year. I will send you a copy when done. You can judge for yourself what I can do. As I will be judging you by the games you make.

Your words would not fail if you would be able to accept they might have been wrong later on. My fault is i'm too provocative so i make it hard for you. Sorry for that - i'll try to improve myself.

I can't take the challenge, because i did not work on a game the last decade. But looking towards the copy anyways - for fun, not to judge you.

I think you can do a lot. You know a lot about everything, enough to make games. I don't think i underestimate your skills. But sometimes your thoughts appear shortsighted to me. This is because we have very different perspective / starting point:

Your goal is to achieve state of the art with your work on games. State of the art is all there is and there is nothing after it.

My goal is to improve state of the art with my work on technology. State of the art is just the start. Finding out what comes next is my work. So i see and think about many things you do not. Physics simulation in games is a sleeping princess with huge potential. It opens up more possibilities and is more important for realism than photorealistic rendering. 

You once said you spend some time to learn 'most' about any field, but learning all the remaining details would take too much time. Better to progress in learning the next field, so you are capable of everything well enough to produce results in the end.

This makes sense and is good practice, but it also implies: likely you're not a expert in most things. Sounds provoking but that's not what i intend. I can just hope you see what i mean. I've made a small physics engine in the past, including constrained multibody stuff, and you remember my work about walking ragdolls. This is why i think i know more about physics than you do, and why i allow myself trying to correct you.

So, looking towards the next debate where we manage to upset each other and hopefully have some fun, ;D

but be sure i respect you as a person, your skills and the help you provide.

7 hours ago, JoeJ said:

Physics can even be considered a graphics element most of the time, only there to make things look more realistic or dynamic

Really, it depends from game concepts. Some developers have as target to develop a arcade games. Its game mechanics usualy use non-realistic phisics. For example space arcade usualy use a aproaches that make a piloting of spasechip similar to piloting of airplane, but its can not by similar by phisics laws. So they just raplece real phisics by dummy game mechanics like maximal speed and turn radius. Simulate a realistic space piloting is not so hard, but it would be about impossible to play. Just becouse real spaceship controlled by  two sticks and orbital piloting require a very advancet pilots skills. Really, top air force pilots spending a years of training to become a spaceships pilots. So space simulation game just can not be phisical realistic, until it ordered by NASA for real spacepilots trainig purposes.

But other games really have to involve a realistic phisics into their game mechanics to be playable. For example a air combat simulators.