#include "timer.h"

#define fb_width  1024
#define fb_height 1024 

static char surface [ fb_width * fb_height ];


void drawPixel ( unsigned x, unsigned y ) {
	*(surface + y * fb_width + x) = 1;
}


void bresenham ( unsigned x1, unsigned y1, unsigned x2, unsigned y2 ) {
	unsigned x, y;
	int dx, dy;
	int incx, incy;
	int balance;


	if ( x2 >= x1 ) {
		dx = x2 - x1;
		incx = 1;
	} else {
		dx = x1 - x2;
		incx = -1;
	}

	if (y2 >= y1) {
		dy = y2 - y1;
		incy = 1;
	} else {
		dy = y1 - y2;
		incy = -1;
	}

	x = x1;
	y = y1;

	if ( dx >= dy ) {
		dy <<= 1;
		balance = dy - dx;
		dx <<= 1;

		while ( x != x2 ) {
			drawPixel ( x, y );
			if ( balance >= 0 ) {
				y += incy;
				balance -= dx;
			}
			balance += dy;
			x += incx;
		}
		drawPixel ( x, y );
	} else {
		dx <<= 1;
		balance = dx - dy;
		dy <<= 1;

		while (y != y2) {
			drawPixel ( x, y );
			if ( balance >= 0 ) {
				x += incx;
				balance -= dy;
			}
			balance += dx;
			y += incy;
		}
		drawPixel ( x, y );
	}
}

#define loops 1

int main ( ) {
	unsigned a;
	unsigned loop, z;
	START_TIMER ( );

//	for ( loop = 0; loop < loops; loop ++ ) {
		for ( z = 0; z < fb_width; z++ ) {
			// Draws in all directions
			bresenham ( 0,0, fb_height - 1, z );
			bresenham ( 0,0, z, fb_height - 1 );
 
			bresenham ( fb_height-1,0, z,fb_height - 1 );
			bresenham ( fb_height-1,0, 0,z );
 
			bresenham ( fb_height-1,fb_height-1, 0, z );
			bresenham ( fb_height-1,fb_height-1, z, 0 );
 
			bresenham ( 0,fb_height-1, z, 0 );
			bresenham ( 0,fb_height-1, fb_height-1, z );
		}
//	}

	STOP_TIMER ( );
	return 0;
}