[TH3_L33T]

So I am having troubles with my camera and my player I have a 2D array full with tile map and the camera allows scrolling through all of it but when the camera hits the edge to let the player continue moving around relative to the camera. I am not exactly sure how to describe it but like a 2D top down view game.

Any help would be appreciated.

[Lord Ned]

Make the camera follow the player.
Then check if the camera is past an edge. If so, align it as close as you can.

Should let the player walk around freely (he should do his own checks against the edge of the world), and keep your camera from extending past.

[Tamschi]

I'm looking for a .NET library that lets me write (and read, if there's one that does both) videos by pushing frames and audio data.

Holly would be perfect, but I'm not good enough at wrapping with P/Invoke / C++/CLI to use it.

[swift and shift]

garry wrote one, but it's in C++ so expect to do some pretty heavy binding

[Tamschi]

swift and shift posted:

garry wrote one, but it's in C++ so expect to do some pretty heavy binding

Tamschi posted:

Holly would be perfect, but I'm not good enough at wrapping with P/Invoke / C++/CLI to use it.

[swift and shift]

oops, how did i miss that

[Armandur]

After compiling SFML2 for VS2010 C++ I'm getting a strange error when building, that I can't fix.
One of the headers in SFML (err.hpp) complains that it can't find ostream.

Output

1>ClCompile:
1>  Application.cpp
1>C:\lib\sfml2.0\include\SFML/System/Err.hpp(32): fatal error C1083: Cannot open include file: 'ostream': No such file or directory
1>
1>Build FAILED.

Application.cpp

#include <SFML/Graphics.hpp>

int main()
{
	sf::RenderWindow Window(sf::VideoMode(800, 600, 32), "SFML Sample Application");

	while (Window.IsOpened())
	{
		sf::Event Event;
		while (Window.PollEvent(Event))
		{
			switch (Event.Type)
			{
			case sf::Event::Closed:
				Window.Close();
				break;
			default:
				break;
			}
		}

		Window.Clear(sf::Color(0, 255, 255));
		Window.Display();
	}

	return 0;
}

[mechanarchy]

I have code resembling the following.

class Example
{
    // ctor, dtor, etc-tor

    template<typename R, typename T>
    R operator()(T a, T b) { /* code */ }
};

How do I actually go about calling the functor with a specific type? In this example, the return type. Simply doing

Example instance(ctor, args);
instance<int, bool>(true, false);

won't work. (I'm also guessing that this IS valid code, the compiler hasn't complained about it but I suppose it could be in undefined behaviour territory)

[AtomiCasd]

Armandur posted:

After compiling SFML2 for VS2010 C++ I'm getting a strange error when building, that I can't fix.
One of the headers in SFML (err.hpp) complains that it can't find ostream.

Output

1>ClCompile:
1>  Application.cpp
1>C:\lib\sfml2.0\include\SFML/System/Err.hpp(32): fatal error C1083: Cannot open include file: 'ostream': No such file or directory
1>
1>Build FAILED.

Application.cpp

#include <SFML/Graphics.hpp>

int main()
{
	sf::RenderWindow Window(sf::VideoMode(800, 600, 32), "SFML Sample Application");

	while (Window.IsOpened())
	{
		sf::Event Event;
		while (Window.PollEvent(Event))
		{
			switch (Event.Type)
			{
			case sf::Event::Closed:
				Window.Close();
				break;
			default:
				break;
			}
		}

		Window.Clear(sf::Color(0, 255, 255));
		Window.Display();
	}

	return 0;
}

You should post this on the sfml-dev.org forum, I believe laurent can help you out since it's a developer build and he's the one developing it.

[Jimbomcb]

I'm trying to create a handheld effect for a camera by interpolating the camera back and forth to random points within a range, however it just looks dumb and nothing at all like I want it to.

I know it's vague and barely a question but yeah, anyone have any input/ideas on how they would (by offsetting the position) achieve a sorta shaky handheld effect?

[ROBO_DONUT]

Jimbomcb posted:

I'm trying to create a handheld effect for a camera by interpolating the camera back and forth to random points within a range, however it just looks dumb and nothing at all like I want it to.

I know it's vague and barely a question but yeah, anyone have any input/ideas on how they would (by offsetting the position) achieve a sorta shaky handheld effect?

Try something like:

yaw_offset = scale * (cos(a*t) + cos(b*t) + cos(c*t));
pitch_offset = scale * (cos(d*t) + cos(e*t) + cos(f*t));

Where a, b, c, d, e, and f are a bunch of coprime coefficients for angular frequency.

[esalaka]

Guys

Is this still a valid description of frustum culling or is there some ~~NEW TECHNOLOGY~~ that simplifies it or makes the process more efficient?

[ROBO_DONUT]

esalaka posted:

Guys

Is this still a valid description of frustum culling or is there some ~~NEW TECHNOLOGY~~ that simplifies it or makes the process more efficient?

Frustum culling is basic geometry. The basic process doesn't change.
Obviously, some scene structures are better suited than others (i.e. hierarchical structures are better than flat structures), but anything you read in an old article probably still works today.

Speaking of which, I've been thinking about breaking the frustum/occlusion culling (well, it's just frustum culling now, but I've got occlusion culling planned out on paper) code from my engine and making it into a dedicated library. It's the sort of thing every game developer really needs, but AFAIK, there isn't really a good library for it right now, short of proprietary middleware.

[Jimbomcb]

ROBO_DONUT posted:

Try something like:

yaw_offset = scale * (cos(a*t) + cos(b*t) + cos(c*t));
pitch_offset = scale * (cos(d*t) + cos(e*t) + cos(f*t));

Where a, b, c, d, e, and f are a bunch of coprime coefficients for angular frequency.

looks awesome, thanks. just out of interest, why do the coefficients need to be coprime

[mechanarchy]

This error is pissing me right the fuck off.

main.cpp:307: error: no matching function for call to ‘layer::debug::Library::findFunction(const char [19])’

main.cpp

layer::debug::Library sqlite("/usr/lib/libsqlite3.so");

const char* (*whatwhat)() = sqlite.findFunction<const char*, void>("sqlite3_libversion"); // line 307

const char* ver3 = whatwhat();

::layer::info("blah says \"%s\"\n", ver3); // printf-equiv

Library is defined as

class Library
{
public:
	Library(const GString& path); // GString is typedef'd std::string
	~Library();
	
	void* findFunction(const GString& functionName) const;
	
	template<typename R, typename... T>
	R (*findFunction(const GString& funcName))(T... Ts) const
	{
		return (R (*)(...))findFunction(funcName);
	}
	
private:
	void* _libraryHandle;
	
};

Compiling with -std=c++0x -pedantic -Wall

Edited:

if I use the non-templated function and some bullshit casting, it works fine.

void* simple = sqlite.findFunction("sqlite3_libversion");

const char* (*simpleimpl)(void) = (const char* (*)(void))(simple);

::layer::info("blah says \"%s\"\n", simpleimpl());

[halofreak472]

Using QT4 in Ruby, how can I set a variable equal to what was entered into lineEdit? I've spent the past hour googling this, and I haven't had any luck. The results I got showed bits of code that were of no relevance to what I'm looking for.

[ROBO_DONUT]

Jimbomcb posted:

looks awesome, thanks. just out of interest, why do the coefficients need to be coprime

You get a longer period before the pattern repeats. It won't appear to be random movement if they have a small common factor.

[kaukassus]

creating an xml file with .net in c#, it works, but the generated file only uses 1 line like this:

<?xml version="1.0"?><Client><server>192.168.12.1</server></Client>

But i want it to look much more organized, like this:

<?xml version="1.0"?>
<Client>
	<server>192.168.12.1</server>
</Client>

This is the code I currently have:

            XmlTextWriter textWriter = new XmlTextWriter("preferences.xml", null);
            textWriter.WriteStartDocument();
            //Start write

            textWriter.WriteStartElement("Client");
            textWriter.WriteStartElement("server");
            textWriter.WriteString("192.168.12.1");
            textWriter.WriteEndElement();
            textWriter.WriteEndElement();


            //End Write
            textWriter.WriteEndDocument();
            textWriter.Close();

[NovembrDobby]

Hmm, you could try:

textWriter.Settings.NewLineOnAttributes = true;

[NovembrDobby]

On ubuntu 11.10 (64 bit), my cmake can't seem to find the xrandr library:



even though I can use it in the terminal:



(using cmake 2.8.5).

Edited:

Fixed, had to install the dev versions of everything (e.g. libsndfile-dev)

[Within]

I'm getting some weird shit here. I'm writing a backup utility for all my stuff and I'm getting 'access denied' to non-system paths when using the System.IO.File.Copy method. I even changed the manifest to requireAdministrator and it didn't help.
Any ideas?

Edited:

One of the paths in question is: C:\Users\.\Desktop\Minecraft\Server

Edited:

Haha, that's unfortunate for me, I just realized I'm using File.Copy in an attempt to copy folders. Sorry - nevermind me.

[PieClock]

In LOVE is there any way I can open a directory in an explorer window?

[mechanarchy]

PieClock posted:

In LOVE is there any way I can open a directory in an explorer window?

I'm not too crash hot with love or lua but some quick googling says there's "os.execute". Just do that and call

os.execute("explorer \"directory name here with spaces\"")

[PieClock]

Yep, just stumbled upon that myself there now. Works great. Thanks

Though this is what I'm doing:

os.execute("C:\\windows\\explorer.exe /e, C:\\")

[Plastical]

This is for a problem on an assignment. I'm having trouble sorting three numbers in order of ascension without the use of array, here's what I have in Java so far:

System.out.println("Enter the first number: ");
int num1= input.nextInt();
				
System.out.println("Enter the second number: ");
int num2 = input.nextInt();
int minInput = Math.min(num1, num2);
int maxInput = Math.max(num1, num2);
		
System.out.println("Enter the third number: ");
int num3= input.nextInt();
minInput = Math.min(minInput, num3);
maxInput = Math.max(maxInput, num3);
				
System.out.println("Numbers in order: " + minInput + " " + maxInput);

The problem is that I can't seem to figure out how to get the middle value. Any help appreciated.

[mechanarchy]

Plastical posted:

This is for a problem on an assignment. I'm having trouble sorting three numbers in order of ascension without the use of array, here's what I have in Java so far:

code

The problem is that I can't seem to figure out how to get the middle value. Any help appreciated.

I'd skip the whole 'min' and 'max' approach and just check for all the combinations using "if a < b and a < c" sort of things.

Edited:

Not particularly glamorous, but it works for something of this small scale.

[Plastical]

mechanarchy posted:

I'd skip the whole 'min' and 'max' approach and just check for all the combinations using "if a < b and a < c" sort of things.

Edited:

Not particularly glamorous, but it works for something of this small scale.

I did this using 9 if statements. It wasn't beautiful and I had to create a temporary variable, but it worked. Thanks.

[mechanarchy]

Plastical posted:

I did this using 9 if statements. It wasn't beautiful and I had to create a temporary variable, but it worked. Thanks.

Yeaah... I kinda expected it would look a bit dreadful.

Edited:

Just decided to see how it was done. Here's a working python implementation:

a = int(raw_input("first: "))
b = int(raw_input("second: "))

theMin = min(a, b)
theMax = max(a, b)

c = int(raw_input("third: "))

theMid = 0

if min(c, theMin) == theMin and max(c, theMax) == theMax:
	# c is middle
	theMid = c
elif min(c, theMin) == theMin:
	# c is max
	theMid = theMax
	theMax = c
else:
	# c is min
	theMid = theMin
	theMin = c

print "minimum value:", theMin
print "middle value:", theMid
print "maximum value:", theMax

Edited:

It's completely different to what I suggested and far closer to what you had, but oh well. When I started writing it, this was how it turned out compared to what I'd planned.

[kaukassus]

what would be the best way to integrate Lua into c#?

[ief014]

kaukassus posted:

what would be the best way to integrate Lua into c#?

http://code.google.com/p/luainterface/

[Leonmyster]

I need some help with this problem. (C++)

2. Write a program that will prompt the user for a positive integer n, and will use a recursive function to convert n to binary. For example, if n is 19, the output shold be 10011. It should then print the binary number.

#include <iostream>
using namespace std;

int convertToBinary(int);

int main()
{
	int n;
	cout << "Enter non-zero integer or 0 to stop: ";
	cin >> n;
	while (n != 0)
	{
		int binary = convertToBinary(n);
		cout << "The binary of integer " << n << " is " << binary << ".\n";

		cout << "Enter non-zero integer or 0 to stop: ";
		cin >> n;
	}
	cout << "Bye!\n";
}

int convertToBinary(int n)
{
	if (n == 0)
		return 0;
	return convertToBinary(n/2) + n%2;
}

I don't know where to go from here, it's adding the numbers together, and that's not what I want. Any ideas on what I'm doing wrong?

[Octave]

Leonmyster posted:

I need some help with this problem. (C++)

2. Write a program that will prompt the user for a positive integer n, and will use a recursive function to convert n to binary. For example, if n is 19, the output shold be 10011. It should then print the binary number.

#include <iostream>
using namespace std;

int convertToBinary(int);

int main()
{
	int n;
	cout << "Enter non-zero integer or 0 to stop: ";
	cin >> n;
	while (n != 0)
	{
		int binary = convertToBinary(n);
		cout << "The binary of integer " << n << " is " << binary << ".\n";

		cout << "Enter non-zero integer or 0 to stop: ";
		cin >> n;
	}
	cout << "Bye!\n";
}

int convertToBinary(int n)
{
	if (n == 0)
		return 0;
	return convertToBinary(n/2) + n%2;
}

I don't know where to go from here, it's adding the numbers together, and that's not what I want. Any ideas on what I'm doing wrong?

Well for one thing, you want it to build a string, while instead it's adding integers together.

[Leonmyster]

Octave posted:

Well for one thing, you want it to build a string, while instead it's adding integers together.

How would I incorporate the string? From what I understand, I can't return it as a string because it's an integer, convertToBinary that is.

My knowledge of strings aren't too good, since my previous professor never taught us string, while this one is all about it.

[Octave]

Leonmyster posted:

How would I incorporate the string? From what I understand, I can't return it as a string because it's an integer, convertToBinary that is.

My knowledge of strings aren't too good, since my previous professor never taught us string, while this one is all about it.

I'd like to preface this with the fact that my C++ is very limited but for starters, you can change the return type to be a string

string convertToBinary(int n)
{
	static string result; // Static so that it will remain between calls of this function rather than being initialized every time
        if (n == 0)
		return 0;
        result.append((n % 2) ? "1" : "0");
	return convertToBinary(n/2);
}

Haven't tested this yet, but it's a start.

[Ziks]

That would just return 0. Maybe try something like:

string convertToBinary( int n )
{
    if( n == 0 )
        return "0";

    return convertToBinary( n / 2 ).append( toString( n % 2 ) ); 
}

Edited:

No idea how to append to a string in C++ though, maybe with a stream

[esalaka]

A lot of the time you want to use stringstreams to convert things into strings.
Read more about 'em here.

Should explain the concept adequately, seeing as you know how streams work already (cin, cout).

Maybe I should learn how to read

[Octave]

Okay, fixed some things, this works but the output is reversed, looking for a string reversal function now...

string convertToBinary(int n)
{
        static string buf;
        if (n == 0) return buf;
        buf.append((n % 2) ? "1" : "0");
        return convertToBinary(n/2);
        
}

[ROBO_DONUT]

Avoid recursion when it isn't beneficial. If you use it in places where there aren't small upper bounds on the depth of the recursion, you risk a stack overflow. Not to mention the function call overhead.
This would probably be better:

string convertToBinary(int n)
{
	int bits = 8 * sizeof(int);
	int mask = 1 << bits - 1;
	string result;
	for (int i=0; i < bits; i++) {
		result.append(n & mask ? "1" : "0");
		mask >>= 1;
	}
	return result;
}

[Ziks]

Instead of reversing the string at the end you could construct it in the opposite order. Also, I'm not sure you can declare static variables inside a method C++, although it has been a while since I last used it.

[ROBO_DONUT]

Ziks posted:

Also, I'm not sure you can declare static variables inside a method C++, although it has been a while since I last used it.

It's a function, not a method.