Game Development

I'm struggling with this stuff. I need to send a request to the server to do some processing, then get the result back. Asking for a file seems easy enough. But what if I want to run a script on the server and get output from it? I'm stuck.

Kevin van der Velden

Dec 4 '13 at 17:30, by Josh Petrie

i.e., "don't ask to ask, just ask."

@Jovito how so? As far as the client concerned it's just calling a file

Almo

I use php to do that.

user92578

Why does adding the virtual to this virtual ~CBounding(); cause a linking error?

Kevin van der Velden

It neither knows nor cares that it's dynamically generated

@Tyyppi_77 depends on the linking error

Jovito

@KevinvanderVelden What's your point?

Almo

3:09 PM

hmm virtual destructor?

doesn't sound right to me

each class gets a destructor, so there's no need to virtual it.

I think

:)

Kevin van der Velden

@Jovito that there is no difference between asking sending a request to a server for some processing and a request for a file. Excepting the URL

user92578

It's a C++ thing @Almo

TreDubZedd

Vitrual destructors are vital in C++

Kevin van der Velden

@Almo uuh, in C++? Yes make every destructor virtual

user92578

Yeah

Almo

3:10 PM

I thought they already were

Kevin van der Velden

(Where every means: Basically every one where there's inheritence involved in any way)

user92578

Yeah

Kevin van der Velden

@Almo nothing is virtual unless you say it's virtual =p

user92578

I'm getting memory leaks because destructors are not getting called

Kevin van der Velden

MOAR virtuals!

TreDubZedd

3:11 PM

C++ doesn't assume anything, except that you, the developer, know what you're doing.

user92578

pastebin.com/SBwjmSTM

TreDubZedd

In the case where C++ is mistaken on that count, you, the developer, will suffer the consequences.

user92578

I can't see why adding a "virtual" would break anything

TreDubZedd

Have you implemented the destructors for the sub-classes?

Kevin van der Velden

Wait, do you have a destructor with arguments?

user92578

3:13 PM

@TreDubZedd yeah, I just figured that

user92578

@KevinvanderVelden no

user92578

is that even possible?

Kevin van der Velden

It is possible to type it, it is not possible to use it =p

user92578

now runs fine with CBoundingCircle desctuctor implemented

Kevin van der Velden

Ooh I see

If you make something virtual you need it to exist, cause it will be referenced in the vtable

Jovito

3:14 PM

@KevinvanderVelden so you're saying when I request a script it should give me back the result?

Kevin van der Velden

@Jovito yep, same as with a static file, no difference what so ever to javascript.

Jovito

say, a python script, for instance...

same?

Kevin van der Velden

Yep, javascript can't care about what is running on the server

TreDubZedd

All the browser knows (javascript included) is Request-Response.

SpartanDonut

Well... you aren't literally requesting a script

Jovito

3:15 PM

hm

SpartanDonut

Just saying that in case it isn't obvious

Kevin van der Velden

It's all just locations and locations are configurable anyway so you can write your script in python and say it's called "index.asp"

If you can open the URL in the browser via the URL bar you'll get the same result from an AJAX call

TreDubZedd

Conversely, if you can make an AJAX call, you can open the same in the browser (though it may look odd)

Jovito

ok, but the script would have to return something that js understands right?

Kevin van der Velden

JS just get's whatever the script returns, whatever you program the JS to understand it will understand

Also: I dislike the term AJAX. It means Asynchronous Javascript And XML. Noone uses XML with it, why are we still calling it AJAX?

Almo

3:20 PM

hahaha

good point

user92578

XML all the things!

TreDubZedd

AJSON?

user92578

(I use XML)

TreDubZedd

doesn't exactly roll off the tongue

Kevin van der Velden

AJAJ ;p

TreDubZedd

3:21 PM

sounds like someone needs the Heimlich

user92578

haha

SpartanDonut

@KevinvanderVelden because jquery

Jovito

What I meant to ask is if you can just return, for instance, a python built-in type, a string. It seems to me that it wouldn't work. Woudn't I have to return to the client whatever the result is as xml or json?

SpartanDonut

Also XMLHttpRequest

@Jovito XML and JSON certainly are common but not required

Kevin van der Velden

@Jovito yes, the ultimate channel you are sending data over is text (well, unless you are insane). It needs to be some text based format

SpartanDonut

3:27 PM

XMLHttpRequest

XMLHttpRequest (XHR) is an API available to web browser scripting languages such as JavaScript. It is used to send HTTP or HTTPS requests to a web server and load the server response data back into the script. Development versions of all major browsers support URI schemes beyond http and https, in particular, blob URLs are supported. Data from the response can be used to alter the current document in the browser window without loading a new web page, and despite the name of the API, this data can be in the form of not only XML, but also JSON, HTML or plain text. The response data can also b...

Jovito

I'm still somewhat confused about how this works but anyway, I'll go over the concepts again and hopefully it will click. Thanks.

Kevin van der Velden

Javascript <-> text channel <-> HTTP Server <-> Your python script

SpartanDonut

My gut says you aren't familiar with web servers and how a script would provide a result through a URL perhaps?

If so, maybe investigate building a REST service with python

Jovito

@SpartanDonut Yep, I just started learning back-end, messed around with flask and django and node, but I haven't quite grasped some concepts yet.

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