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Cryengine Source Code

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Re: Cryengine Source Code

#71

Post by skohan »

oneshot96 wrote: post #69
skohan wrote: post #44

Earlier quoted context omitted.

As a hobbyist who likes to tinker with game and interactive media development, a sentiment I often come across is that in 2020 it makes no sense to implement a game engine, and that I should just use something which already exists to avoid re-inventing the wheel. Code like this is one thing which helps me to calmly ignore than sentiment. I came across the same kind of thing when I was kicking the tires on the Unreal…

Well duh, this is a physics engine. Implement double jump by placing an invisible floor underneath the player object when you decrement the counter.

I cannot tell if you are joking or not, but needing to place an entity into the world for a single frame to accomplish this rather than simply applying an impulse to the player is precisely the kind of over-complication I'm referring to

Re: Cryengine Source Code

#72

Post by pm90 »

ConcernedCoder wrote: post #67
elwell wrote: post #53

Earlier quoted context omitted.

There are other reasons for separating logic into functions besides just keeping it DRY. It's an opportunity to encapsulate concerns and then, in some other place, compose the story poetically and clearly.

...which is NOT high on the list of concerns for a game title, what you want instead is massive performance gains, so you can do more with less, and in the end produce a better experience than your competitor. -- function calls/indirection/making your code 'easy' to understand, all have a RUNTIME cost, and many small costs add up to a large cost, the reasoning is really that simple.

I struggle to see how composing into functions adds a runtime cost when using modern compilers; as others have pointed out the compiler will inline it if the function is only used once.

This rationalization doesn’t make sense to me, especially for game engines which I assume are not limited to a release or 2 but are used to power multiple titles. If the software artifact is going to live for a long time, it’s probably worth the effort to make it easier to understand and test.

Re: Cryengine Source Code

#73

Post by nolaspring »

Nican wrote: post #13

This is on the front page again. Please take some time to read this wonderful function: https://github.com/CRYTEK/CRYENGINE/blob/release/Code/CryEng... EDIT: That whole function is a minefield. Just taking a quick look: * 814 lines of code * goto inside 3 nested for-loops * macros * commented out code * new/delete, with no RAII * thread specific variables and locks (?)

Also Requires visual studio

Re: Cryengine Source Code

#74

Post by layoutIfNeeded »

Nican wrote: post #13

This is on the front page again. Please take some time to read this wonderful function: https://github.com/CRYTEK/CRYENGINE/blob/release/Code/CryEng... EDIT: That whole function is a minefield. Just taking a quick look: * 814 lines of code * goto inside 3 nested for-loops * macros * commented out code * new/delete, with no RAII * thread specific variables and locks (?)

"You may not like it, but this is what peak performance looks like."

Re: Cryengine Source Code

#75

Post by messe »

Jasper_ wrote: post #45
Nican wrote: post #13

This is on the front page again. Please take some time to read this wonderful function: https://github.com/CRYTEK/CRYENGINE/blob/release/Code/CryEng... EDIT: That whole function is a minefield. Just taking a quick look: * 814 lines of code * goto inside 3 nested for-loops * macros * commented out code * new/delete, with no RAII * thread specific variables and locks (?)

I don't think it's the best code I've ever seen, but a lot of these are surface-level complaints. > * goto inside 3 nested for-loops. C has no pattern for breaking out of multiple for loops at the same time. Other languages like Java and JavaScript introduced "break label;" to handle this edge case. goto is perfectly acceptable to break out of multiple loops. > * new/delete, with no RAII They use RAII, but it's not a…

> C has no pattern for breaking out of multiple for loops at the same time. Other languages like Java and JavaScript introduced "break label;" to handle this edge case. goto is perfectly acceptable to break out of multiple loops.

Yeah, that's not what it does. The code looks like this:

    if (pgeom->Intersect(pentlist[i]->m_parts[j].pPhysGeomProxy->pGeom, gwd,gwd+1, &ip, pcontacts)) {
            got_unproj:
            if (dirUnproj.len2()==0) dirUnproj = pcontacts[0].dir;
            t = pcontacts[0].t;     // lock should be released after reading t
            return t;
    }       
    for(int ipart=1;ipartm_parts[j].flags) {
            gwd[2].R = Matrix33(qrot); 
            gwd[2].offset = pos + qrot*m_parts[ipart].pos;
            gwd[2].scale = m_parts[ipart].scale;
            gwd[2].v = -dirUnproj;
            if (m_parts[ipart].pPhysGeomProxy->pGeom->Intersect(pentlist[i]->m_parts[j].pPhysGeomProxy->pGeom, gwd+2,gwd+1, &ip, pcontacts))
                    goto got_unproj;
            }
    }
Notice (a) the if statement on the same line as the for loop, and (b) the fact that the goto jumps out of a conditional inside a for loop inside of a conditional into a conditional just before the for loop.

EDIT: Just realised the poster is referring to a different function.

IMO this one is more horrifying.

Re: Cryengine Source Code

#76

Post by Jasper_ »

messe wrote: post #75
Jasper_ wrote: post #45

Earlier quoted context omitted.

I don't think it's the best code I've ever seen, but a lot of these are surface-level complaints. > * goto inside 3 nested for-loops. C has no pattern for breaking out of multiple for loops at the same time. Other languages like Java and JavaScript introduced "break label;" to handle this edge case. goto is perfectly acceptable to break out of multiple loops. > * new/delete, with no RAII They use RAII, but it's not a…

> C has no pattern for breaking out of multiple for loops at the same time. Other languages like Java and JavaScript introduced "break label;" to handle this edge case. goto is perfectly acceptable to break out of multiple loops. Yeah, that's not what it does. The code looks like this: if (pgeom->Intersect(pentlist[i]->m_parts[j].pPhysGeomProxy->pGeom, gwd,gwd+1, &ip, pcontacts)) { got_unproj: if (dirUnproj.len2()==0…

That's in a different function, so I wasn't counting it, but sure. I mean, I would write it differently, but it's fairly readable. It's jumping to a common function epilogue once it finds something it can collide with. Seriously -- try reading through it rather than gawking at the goto.

Re: Cryengine Source Code

#77

Post by Jasper_ »

skohan wrote: post #71
oneshot96 wrote: post #69

Earlier quoted context omitted.

Well duh, this is a physics engine. Implement double jump by placing an invisible floor underneath the player object when you decrement the counter.

I cannot tell if you are joking or not, but needing to place an entity into the world for a single frame to accomplish this rather than simply applying an impulse to the player is precisely the kind of over-complication I'm referring to

Without having read any of the Unreal Engine movement code, there's a complication here, and that is that "jump" might be influenced by the floor that the player is standing on. The force impulse might be related to the slope in some way. You have to figure out what "double jump" means in the context of there being no floor.

Placing a floor that has the influences you want under the player is, in a sense, a hack, but not an entirely misguided one. A better design might be not relying on whatever the "jump" button does, but writing your own, e.g. applying an impulse to the player directly.

If this sounds like semantics, consider a game like Super Mario Galaxy, which has spherical worlds. How do you determine the correct impulse for which way a "jump" goes? This is where these sorts of complications come from.

Re: Cryengine Source Code

#78

Post by Nextgrid »

user5994461 wrote: post #70
Nican wrote: post #35

Earlier quoted context omitted.

Not going to lie, playing Crysis was a lot of fun, and I never knew this was the underneath function running it.

Crysis shipped with a full blow SDK that included most of its source code. You could actually rebuild the game from it, the 50MB dll that controlled the whole game. Old players maybe remember that the crysis multiplayer was the most cheated game in its era. It was totally unplayable due to all the cheating and that killed the game. One way to make cheats. You could load up the SDK in visual studio. Find the code that…

Was ammo in Crysis controlled client-side? I've always assumed such counters were stored server-side and thus a server won't apply a "fire" event if the player's ammo counter is at zero until it receives a "reload" event to reset the counter.

Re: Cryengine Source Code

#79

Post by squarefoot »

jokoon wrote: post #63
remram wrote: post #18

Earlier quoted context omitted.

> things that are not open source are rarely not well written I think you got lost in your triple negative there

yes, english is not my main language, thanks for the correction

Openness aside, working under constant pressure with crazy deadlines also paves the way for ugly/barely tested/hard to maintain code. Game studios often have extremely strict deadlines, but I've experienced this pressure also when working in government software; this code looks like examples from Dr Dobb's compared to the pile of crap we sometimes could barely stick together in the old days.

Re: Cryengine Source Code

#80

Post by userbinator »

Nican wrote: post #13

This is on the front page again. Please take some time to read this wonderful function: https://github.com/CRYTEK/CRYENGINE/blob/release/Code/CryEng... EDIT: That whole function is a minefield. Just taking a quick look: * 814 lines of code * goto inside 3 nested for-loops * macros * commented out code * new/delete, with no RAII * thread specific variables and locks (?)

I'd rather work with this than Enterprise Java.

At least the logic is all there and you only need to scroll to see it, instead of jumping around between a dozen or more different files.

Math-heavy code tends to look dense to those who are accustomed to more "mundane" LOB type applications.

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