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[TheDarkStar]

In c++, is there a good way to be able to use curly brace-enclosed lists for object initialization? The idea is that instead of creating an array and then copying the values from the array into a matrix class, I can just initialize the matrix class with the list of values.

[Reelya]

Since C++11 it's supported initialization lists, so you can probably just declare the array inline with {} then feed it straight in, which should invoke the innate copy constructor (order the data inside the class how you want it fed in to simplify how this would work). Or you write a copy constructor in the class which takes the raw data and copies it in, if it doesn't recognize what to do with the data by itself.

[Reelya]

bump / double post, because I solve the problem TheDarkstar proposed. You can do it but you need to pull in an STL library that does it for you:

Code: [Select]

#include <initializer_list>

class Matrix4x4
{
public:
float data[16];

Matrix4x4(std::initializer_list<float> l)
{
             // create your matrix from the initializers here
};
};

int main()
{
Matrix4x4 m = { 0.0f, 0.0f, 0.0f, 0.0f, 0.0f,0.0f, 0.0f, 0.0f, 0.0f,0.0f, 0.0f, 0.0f, 0.0f,0.0f, 0.0f, 0.0f };

return 0;
}
Obviously there are many ways to get the data into the matrix that don't require the use of a library, but that's the cleanest way to get the initializer list behavior working properly in your client code.

[TheDarkStar]

bump / double post, because I solve the problem TheDarkstar proposed. You can do it but you need to pull in an STL library that does it for you:

Code: [Select]

#include <initializer_list>

class Matrix4x4
{
public:
float data[16];

Matrix4x4(std::initializer_list<float> l)
{
             // create your matrix from the initializers here
};
};

int main()
{
Matrix4x4 m = { 0.0f, 0.0f, 0.0f, 0.0f, 0.0f,0.0f, 0.0f, 0.0f, 0.0f,0.0f, 0.0f, 0.0f, 0.0f,0.0f, 0.0f, 0.0f };

return 0;
}
Obviously there are many ways to get the data into the matrix that don't require the use of a library, but that's the cleanest way to get the initializer list behavior working properly in your client code.

Thanks! Until now my solution was to initialize a matrix and then use an overloading assignment operator, but this code is cleaner and easier to use.

[DragonDePlatino]

What's a good human-readable, non-verbose format for storing data? In my game, I'm defining the information about game entities in JSON like this:

Spoiler (click to show/hide)

Code: [Select]

{
    "rogue": {
        "anim": {
            "timer": 0
        },
        "brain": {
            "type": "PLAYER"
        },
        "image": {
            "visibility": "VISIBLE",
            "texture": "rogue",
            "imagebox": [0, 0, 24, 40],
            "imageoff": [0, -20]
        },
        "player": {},
        "pos": {
            "loc": [0, 0],
            "dir": "SOUTH",
            "solidity": "SOLID"
        }
    },
    "kobold": {
        "anim": {
            "timer": 0
        },
        "brain": {
            "type": "MONSTER"
        },
        "image": {
            "visibility": "VISIBLE",
            "texture": "kobold",
            "imagebox": [0, 0, 24, 40],
            "imageoff": [0, -20]
        },
        "pos": {
            "loc": [0, 0],
            "dir": "SOUTH",
            "solidity": "SOLID"
        }
    }
}

Less verbose than XML, but I think I can do better. Ideally, my dream format would look like this:

Spoiler (click to show/hide)

Code: [Select]

rogue
    anim
        timer 0
    brain
        type "PLAYER"
    image
        visibility "VISIBLE"
        texture "rogue"
        imagebox [0 0 24 40]
        imageoff [0 20]
    player
    pos
        loc [0 0]
        dir "SOUTH"
        solidity "SOLID"
kobold
    anim
        timer 0
    brain
        type "MONSTER"
    image
        visibility "VISIBLE"
        texture "kobold"
        imagebox [0 0 24 40]
        imageoff [0 -20]
    pos
        loc [0 0]
        dir "SOUTH"
        solidity "SOLID"

Like python, everything would be whitespace dependent with very little punctuation. Does anything like this exist or would I need to come up with my own format? I really need to know before I move forward with my game because I'm going to be using the same format for *everything* including file locations, user data, save files, settings, etc.

[Mephisto]

Like python, everything would be whitespace dependent with very little punctuation. Does anything like this exist or would I need to come up with my own format? I really need to know before I move forward with my game because I'm going to be using the same format for *everything* including file locations, user data, save files, settings, etc.

The example provided is almost but not quite YAML. It's still got some punctuation but not as much as JSON. For some reason I don't really see it in use much. The only thing in recent memory I've seen is in Rails confs.

Check out this sample.

[DragonDePlatino]

Wow, YAML looks pretty great!

Spoiler (click to show/hide)

Code: [Select]

rogue:
    anim:
        timer: 0
    brain:
        type: player
    image:
        visibility: visible
        texture: rogue
        imagebox: [0, 0, 24, 40]
        imageoff: [0, 20]
    player:
    pos:
        loc: [0, 0]
        dir: south
        solidity: solid
kobold:
    anim:
        timer: 0
    brain:
        type: monster
    image:
        visibility: visible
        texture: kobold
        imagebox: [0, 0, 24, 40]
        imageoff: [0, -20]
    pos:
        loc: [0, 0]
        dir: south
        solidity: solid

I can live with the colons and the lack of quotation marks is a plus. Unfortunately, it's far more complex than my needs so all of the existing libraries require a lot installation and boilerplate code. At this point I'm considering just rolling my own format. There are JSON parsers out there done in 200 LOC so how hard could it be?

[Skyrunner]

According to the internet, YAML is better suited for config files and JSON is better as a serializable data format and API communication format -- probably because you can tell when you're missing a part of a file with JSON and you can't do that with YAML.

[Shadowlord]

It's pretty easy to roll your own config file reader. I made one for ini-style files a few years ago, since I didn't want to edit xml files or w/e.

[breadman]

What's a good human-readable, non-verbose format for storing data?

TOML is nice, as something of a cross between YAML and .ini config file format.  Granted, for this particular example, it's not quite as pretty as YAML:

Spoiler (click to show/hide)

Code: [Select]

[rogue]
    anim = { timer = 0 }
    brain = { type = "PLAYER" }
    player = {}
    [rogue.image]
        visibility = "VISIBLE"
        texture = "rogue"
        imagebox = [0, 0, 24, 40]
        imageoff = [0, 20]
    [rogue.pos]
        loc = [0, 0]
        dir = "SOUTH"
        solidity = "SOLID"
[kobold]
    anim = { timer = 0 }
    brain = { type = "MONSTER" }
    [kobold.image]
        visibility = "VISIBLE"
        texture = "kobold"
        imagebox = [0, 0, 24, 40]
        imageoff = [0, -20]
    [kobold.pos]
        loc = [0, 0]
        dir = "SOUTH"
        solidity = "SOLID"

[tonnot98]

I programmed a swastika with a turtle in class today.

It was actually a valid answer for the online lesson.

[McTraveller]

I programmed a swastika with a turtle in class today.

It was actually a valid answer for the online lesson.

This makes me imagine tonnot98 sitting at a desk with a turtle in the chair next to him. They have some programmable swastika, and are working on it together like pair-programming heroes.

[itisnotlogical]

I thought of a swastika with a hand on each end, and each hand is holding some comically unrelated item, one of which is a turtle.

[tonnot98]

Since I feel that I must elaborate, I drew a swastika using the turtle graphics program.

[Reelya]

Since I feel that I must elaborate, I drew a swastika using the turtle graphics program.

I thought of a swastika with a hand on each end, and each hand is holding some comically unrelated item, one of which is a turtle, which is drawing a swastika with a hand on each end, and each hand is holding ...

FTFY