DC Controller Code

[404NotFound]

Ok, I understand the type of code used in examples, where it's as such:

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MAPLE_FOREACH_BEGIN(MAPLE_FUNC_CONTROLLER, cont_state_t, st)
            if (st->buttons & CONT_DPAD_RIGHT)

but, what i'm wondering is how do i get a more powerful control scheme? As in I want to be able to register if two buttons are pressed simultaneously, and how to get multiple controllers working (up to 4)

I've read through all the old posts, even toastman's lengthy explanations, but I'm still not fully getting it here... ideally i'd write a class to do it for me (as that seems the easiest after a little initial work), but I still haven't learned classes yet.

I've also looked through siggler's SmashDC code, which I understand. It is as follows:

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void UpdateControls()
{
	UpdateControlSet( 0 );
	UpdateControlSet( 1 );
	UpdateControlSet( 2 );
	UpdateControlSet( 3 );
}

uint8 GetPortAddr( int port )
{
	uint8 addr;

	addr=maple_addr( port, 0 );

	return addr;
}

int PadInPort( int port )
{
	int retval=FALSE;

	if ( maple_device_func( port, 0 ) == MAPLE_FUNC_CONTROLLER )
		retval=TRUE;

	return retval;
}

void UpdateControlSet( uint8 index )
{
	uint8 mcont = 0;
	cont_cond_t cond;

	mcont = GetPortAddr( index );

	if (cont_get_cond(mcont, &cond))
	{
		//printf("Error getting controller status\n");
	}
	else
	{
		if (!(cond.buttons & CONT_DPAD_UP))
			ControlSets[index].Up=TRUE;
		else ControlSets[index].Up=FALSE;

		if (!(cond.buttons & CONT_DPAD_DOWN))
			ControlSets[index].Down=TRUE;
		else ControlSets[index].Down=FALSE;

		if (!(cond.buttons & CONT_DPAD_LEFT))
			ControlSets[index].Left=TRUE;
		else ControlSets[index].Left=FALSE;

		if (!(cond.buttons & CONT_DPAD_RIGHT))
			ControlSets[index].Right=TRUE;
		else ControlSets[index].Right=FALSE;

		if (!(cond.buttons & CONT_Y))
			ControlSets[index].ShootUp=TRUE;
		else ControlSets[index].ShootUp=FALSE;

		if (!(cond.buttons & CONT_A))
			ControlSets[index].ShootDown=TRUE;
		else ControlSets[index].ShootDown=FALSE;

		if (!(cond.buttons & CONT_X))
			ControlSets[index].ShootLeft=TRUE;
		else ControlSets[index].ShootLeft=FALSE;

		if (!(cond.buttons & CONT_B))
			ControlSets[index].ShootRight=TRUE;
		else ControlSets[index].ShootRight=FALSE;

		if (!(cond.buttons & CONT_START))
		{
			ControlSets[index].Exit=TRUE;
		}
		else
			ControlSets[index].Exit=FALSE;
	}
}

BUT Toastman said that 1.1.8 introduced a new controller API, so the above is probably not working code in 1.1.9. Can someone point out the differeneces?

[Viktor]

You can try to look at my wrapper class for controll input, you can find it on my page, http://www.vgsoftware.com/, there is also a example program with the class. But its all in C++ and uses classes so it helps if you know how to use classes.

/Viktor

[BlackAura]

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if (!(cond.buttons & CONT_A)) 

becomes

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if (st->buttons & CONT_A)

and the ports thingy is different now.

Just using C, you can get the status of whichever controller you like by using the following function. 0 is the first controller, 1 is the second, 2 is the third, and 3 is the fourth. It returns a pointer to the controller status, or NULL if there aren't that many controllers.

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cont_state_t padGetState(int padnum)
{
	maple_device_t	*dev;
	cont_state_t	*state;

	// Find a controller 
	dev = maple_enum_type(padnum, MAPLE_FUNC_CONTROLLER);
	if(!dev)
		return NULL;

	// Get controller state
	state = (cont_state_t *)maple_dev_status(dev);
	if(!state)
		return NULL;

	// Return the state structure
	return state;
}

Now, once we have that status structure, we need to know how to use it. You can get the status of the first controller like this

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cont_state_t *state;
state = padGetState(0);

Next, you need to know how to read a button. The variable buttons[/b] contains the status of all the buttons, stored as bits. Each bit represents one button, and if the bit is turned on (1) then the button is pressed. You can detect if the A button is pressed like this

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if(state-> buttons & CONT_A)
	....

It doesn't matter if multiple buttons are pressed, because that code will only check for one button. If you want to do something when, say, A and B are pressed, you simply combine the test for A and B, like this:

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if( (state->buttons & CONT_A) && (state->buttons & CONT_B) )
	....

You can check the status of all the digital buttons on the controller in this way, you simply replace CONT_A with the name of whichever button you want. Here's the ones that are valid for a standard Dreamcast controller

• A = CONT_A
  B = CONT_B
  X = CONT_X
  Y = CONT_Y
  Start = CONT_START
  D-Pad Up = CONT_DPAD_UP
  D-Pad Down = CONT_DPAD_DOWN
  D-Pad Left = CONT_DPAD_LEFT
  D-Pad Right = CONT_DPAD_RIGHT

[EverStoned]

I was gonna say that.

Or at least the bit about the &&.

[toastman]

Or better yet,

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if( (state->buttons & (CONT_A | CONT_B)) ) 
 //Do stuff here

That will also test the buttons together.

[404NotFound]

K thx guys. I understand it all now.

[EvilSporkMan]

Or better yet,
Code:

if( (state->buttons & (CONT_A | CONT_B)) )
//Do stuff here


That will also test the buttons together.

Maybe you should explain how that's a "binary" OR and what exactly it does, so poor 404 doesn't have to use code he doesn't understand.

[404NotFound]

Or better yet,
Code:

if( (state->buttons & (CONT_A | CONT_B)) )
//Do stuff here


That will also test the buttons together.

Maybe you should explain how that's a "binary" OR and what exactly it does, so poor 404 doesn't have to use code he doesn't understand.

WTF... how did you know...

Yeah, i'm guessing there is a difference between && and &, || and |...

DOH, slipped my mind, & is a pointer.... scratch that.

[BlueCrab]

&& = Logical AND
|| = Logical OR
& = Bitwise AND
| = Bitwise OR

& can also be used to pass some variable by reference. (i.e. pointer)

Here's a page that explains Bitwise operators:
http://www.cs.cf.ac.uk/Dave/C/node13.ht ... 0000000000
Which is a part of this page (that contains a lot of information on C):
http://www.cs.cf.ac.uk/Dave/C/CE.html

[EvilSporkMan]

& isn't a pointer, it's "address of" when used before a variable.

int foo;
int *ptr = &foo;

And thank you, bitwise was the word I wanted

[EverStoned]

reference and constant reference are two different things...that should be noted.

[toastman]

& - a case study

There are many uses for &:

& - Bitwise AND
Using bitwise AND, you will compare the EACH AND EVERY BIT of both the left and right operand. The result will be any and all bits that the two sides have in common.
Example:
110011 & 100001 would return 100001 as those are the common bits.

&& - Logical AND
Logical AND will take two values and see if they are both TRUE, where TRUE is any non-zero number.
Example:
127 && 4 would return non-zero, 0 && 4 would return zero, 0 && 0 would return 0

&<variable>
This unfortunately is dependant on context
When used in a function header like so:

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int My_Function(int &watch_me);

It means to pass the variable "by reference". This means that watch_me is actually a pointer to the original variable. This means that anything you do to this variable in that function will remain after you exit the function.

When used anywhere else, it means to reference a variable, or get the address in memory. There's no good way I can explain it, I hope a short example helps:

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int *pointer;
int variable = 42;

/*To make pointer point to variable, you need to somehow get variable's address to pointer. This is one thing that referencing is good for.*/
pointer = &variable //Now pointer points to variable

There also some functions you'll see in KOS that have definitions like this
int KOS_function(int *wtf);
If you have a normal variable you wish to pass into there, you can also reference it, when you call the function.
KOS_function(&my_variable);

[404NotFound]

Ah i'm crystal now!

As in each controller alias has a different bit definition.. say CONT_A has 001000 and CONT_B has 100000, and you say this:

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if( (state->buttons & (CONT_A | CONT_B)) ) 

It means it does a bitwise OR, and produces 101000, and stores that code as the state of the controller, and since the bitwise state has the combination of both buttons, it then says "hey look, they are both pressed."

K, sweetness.

[ragnarok2040]

Glad that I read this thread as I just made a function with (outa, outb) where those two variables plug into some equations and then spits out values into them, *_*.

/me corrects code

[toastman]

Ah i'm crystal now!

As in each controller alias has a different bit definition.. say CONT_A has 001000 and CONT_B has 100000, and you say this:

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if( (state->buttons & (CONT_A | CONT_B)) ) 

It means it does a bitwise OR, and produces 101000, and stores that code as the state of the controller, and since the bitwise state has the combination of both buttons, it then says "hey look, they are both pressed."

K, sweetness.

Yeah, something like that.

[nymus]

404, I like the way you figured it out, especially since you haven't had prior exposure to binary logic. Good for you man!

Anyways, here's a class i wrote for the contrtoller (KOS-1.1.9)

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#ifndef CONTROLLER_H
#define CONTROLLER_H


#include <kos.h>
/**
 * controller class for handling controllers
 */
 
class Controller {
	private:
	static int IN_USE[4]; //indices in use;//initalize to -1
	
	int mapleIndex; //location on Maple bus for KOS
	uint32 pushedLast; //millisecond
	
	uint32 delay; //millisecond
	
	public:
	Controller() {
		delay = 0;
		pushedLast = 0;
		mapleIndex = -1;//set false first
		
		int i=0;
		while(i < 4) { //four controller ports
			maple_device_t* dev = maple_enum_type(i, MAPLE_FUNC_CONTROLLER);
		
			if(dev) 
				if(IN_USE[i] == -1) {
					mapleIndex = i; //free slot
					IN_USE[i] = 1;
					break;
				}
		
			i++;
		}				
	}
	
	virtual ~Controller() { }
	
	uint32 getDelay() { return delay; }
	uint32 lastPush() { return pushedLast; }
	int getMapleIndex() { return mapleIndex; }
	
	Controller& setDelay(uint32 d) { delay = d; return *this;}
	
	uint32 checkController() {
		uint32 curTime;
		timer_ms_gettime(NULL, &curTime);
		
		if((curTime-pushedLast) > delay) {
			maple_device_t* dev = maple_enum_type(mapleIndex, MAPLE_FUNC_CONTROLLER);
			pushedLast = curTime;
			return ((cont_state_t*)maple_dev_status(dev))->buttons;
		}
		
		return 0;
	}
};
#endif

save it as "Controller.h" and use it as follows:

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int Controller::IN_USE = {-1, -1, -1, -1};

int main() {
	Controller c;

	/**
	 * Check if the contrtoller was found
	 */
	if(c.getMapleIndex() == -1) {
		printf("Error initialising controller!\n");
		return 0;
	}

	/* The DC Controller is very FAST so you can use this
	 * to slow down the button refresh
	 */
	
	c.setDelay(200);

	while(true) {
		uint32 result = c.checkController();
		
		if(result & (CONT_A | CONT_X)) printf("A and X pushed.\n");
				
		else if((result & CONT_DPAD_UP)) printf("UP pushed.\n");
			
		else if((result & CONT_DPAD_DOWN)) printf("DOWN pushed.\n");
				
		else if((result & CONT_DPAD_RIGHT)) printf("RIGHT pushed.\n");
			
		else if((result & CONT_START)) {
			printf("Bored already?\n");
			 return 0;						
		}
	}
}

[Phantom]

Ah i'm crystal now!

As in each controller alias has a different bit definition.. say CONT_A has 001000 and CONT_B has 100000, and you say this:

Code: Select all

if( (state->buttons & (CONT_A | CONT_B)) ) 

It means it does a bitwise OR, and produces 101000, and stores that code as the state of the controller, and since the bitwise state has the combination of both buttons, it then says "hey look, they are both pressed."

That code checks if CONT_A or CONT_B is pressed (or both). If one or both of those buttons is pressed, the result of the bitwise AND will be unequal to zero, i.e. 'true'.

EDIT: See BlackAura's post earlier in this thread for an example of how to check for two buttons being pressed at the same time.

EDIT 2: I just noticed that this thread is over a week old, so this reply is probably useless by now.. bleh.