speedup things

[Unregistered]

How could one make the dos-screen draw faster ?
I *think* that the length of the loop directly affects the execution time, no ?

well here is my code (only the part that draws the screen), if u have any suggestions lets hear em

int draw()
{
	while(yc<=mym && xc<=mxm)
	{
		if(cm[xc][yc]=='\n')
		{
			printf("\n");
			while(b!=0)
			{
				printf("\b");
				b--;
			}
			yc++;
			xc=0;
		}
		if(xc==xl && yc==yl && nm[xc][yc]==0)
		{
			textcolor(character);
			cprintf("@");
			nowrite=1;
		}
		if(flag==1)
		{

		}
		else
		{
			switch(cm[xc][yc])
			{
				/* CONSTRUCTS */
				case '#':
				if(nocolor==0) textcolor(wall);
				break;
				case '.':
				if(nocolor==0) textcolor(grass);
				break;
				case ',':
				if(nocolor==0) textcolor(floor);
				break;
				case '~':
				if(nocolor==0) textcolor(water);
				break;
				case '/':
				if(nocolor==0) textcolor(door);
				break;
				case '+':
				if(nocolor==0) textcolor(doorc);
				nm[xc][yc]=2;
				break;
				case 'E':
				if(nocolor==0) textcolor(enter);
				break;
				default:
				textcolor(def);
				break;
			}
		}
		if(nowrite!=0);
		else if(flag!=0) cprintf("%c",cm[xc-1][yc]);
		else cprintf("%c",cm[xc][yc]);
		xc++;
		b++;
		nowrite=0;
		flag=0;
	}
	xc=0;
	yc=0;
	b=0;
}

thx in advance for any support

[quzah]

if(flag==1)
{

}
else

I'll assume you meant to do this for some vital reason.

switch(cm[xc][yc])
			{
				/* CONSTRUCTS */
				case '#':
				if(nocolor==0) textcolor(wall);
				break;
				case '.':
				if(nocolor==0) textcolor(grass);
				break;
				case ',':
				if(nocolor==0) textcolor(floor);
				break;
				case '~':
				if(nocolor==0) textcolor(water);
				break;
				case '/':
				if(nocolor==0) textcolor(door);
				break;
				case '+':
				if(nocolor==0) textcolor(doorc);
				nm[xc][yc]=2;
				break;
				case 'E':
				if(nocolor==0) textcolor(enter);
				break;
				default:
				textcolor(def);
				break;

This would be much better using a lookup table:

enum { L_wall, L_grass, L_water, L_door, L_doorc, L_enter, L_max };

struct {
    char c;
    int color;
} lookup[] =
{
    { '#', wall },
    { '.', grass },
    { ',', floor},
    { '~', water },
    { '/', door },
    { '+', doorc },
    { 'e', enter },
    { 0, def },
}

Then you slightly modify how you store the data and use the lookup table to pull the correct character and color.

Quzah.

[Unregistered]

Originally posted by quzah

This would be much better using a lookup table:

enum { L_wall, L_grass, L_water, L_door, L_doorc, L_enter, L_max };

struct {
    char c;
    int color;
} lookup[] =
{
    { '#', wall },
    { '.', grass },
    { ',', floor},
    { '~', water },
    { '/', door },
    { '+', doorc },
    { 'e', enter },
    { 0, def },
}

Could u please clarify this a bit or maybe a link to a tutorial ? im no expert in C... *yet*

[quzah]

Do you know what a structure is?
Do you know what an array is?
Do you know how to initialize a structure at declaration?
Do you know how to initialize an array at declaration?

This combines all of the above.

First I made a structure. Since I didn't care if I ever made an instance of this structure, I didn't bother giving it a name. So, we have so far:

struct
{
    char c;
    int i;
}

So you have a structure which contains a character and an integer.

Then we tack on declaring an array, whose size we don't specify, called 'lookup'. This gives us:

struct
{
    char c;
    int i;
} lookup[] =

Since it's size isn't declared, we have to initialize this when we create the variable. To initialize a structure at creation, you do this:

struct <my struct name> <my var name> = { <structure elements> };

So we end up with:

struct
{
    char c;
    int i;
} lookup[] = 
{
    { <the character value>, <the integer value> },
     ... repeat for each additional structure you make ...

};

Got all that?

Quzah.

[Hammer]

>enum { L_wall, <snip>
....
>{ '#', wall },
Are the enum names meant to match the names used in the array? (they have L_ missing)

[quzah]

Originally posted by Hammer
>enum { L_wall, <snip>
....
>{ '#', wall },
Are the enum names meant to match the names used in the array? (they have L_ missing)

Nope.

for( x = 0; x < L_max; x++ )
{
    printf("%c, %d\n", lookup[x].c, lookup[x].i );
}

textcolor( lookup[L_door].i );
cell = lookup[L_wall].c;

He had his defines for colors, as such, you can't use those as simple enums, because their spot in the array more than likely doesn't match their corresponding numeric color value.

Quzah.