Anti aliasing by filtering using a weighted averaging scheme

gistfile1.js

var table = [
	[1,2,1],
	[2,4,2],
	[1,2,1],
];
var tableMaxDim = 3;
var tableSum = 16;
var filterStart = -1;
var filterEnd = 1;

function filter( i, j ) {
	
	// correct index position
	i++;
	j++;
	if( i >= tableMaxDim || j >= tableMaxDim || i < 0 || j < 0 ) {
		return 0;
	}
	
	return table[j][i]/tableSum;
};


// 7 x 7 pixel grid
var screenMaxY = 7;
var screenMaxX = 7;
// image consists of the infinitesimally thin line y = x in white on a black background
function image( x, y ) {
	return x === y ? 1 : 0;
};

var videoMemory = [];

for( var y = 0; y < screenMaxY; y++ ) {
	for( var x = 0; x < screenMaxX; x++ ) {
		
		// sum of j = -1 to 1
		//	sum of i = -1 to 1
		//		h(i,j)f(x+i,y+j)
		// where h(i,j) is the filter function
		// where f(x+i,y+j) represents the scene intensity at point (x,y)
		var inten = 0;
		for( var j = filterStart; j <= filterEnd; j++ ) {
			for( var i = filterStart; i <= filterEnd; i++ ) {
				inten += filter( i, j ) * image( x + i, y + j );
			}
		}
		videoMemory.push( inten );
	}
}

// ouput video screen buffer
// invert y axis
for( var i = 0, y = screenMaxY - 1; y >= 0; y-- ) {
	var row = [];
	for( var x = 0; x < screenMaxX; x++ ) {
		row.push( videoMemory[y*screenMaxX+x]*tableSum );
	}
	console.log( row );
}