I read in stackoverflow before about Bresenham algorithm use for a particular environment like low-language, but I have to compare it in my report so any ideal for my report. How can I prove Bresenham is faster than DDA. Now I created a simple paint on winform C# and the time when I draw with 2 different method is likely equal, sometime DDA is faster. Here is my code in both method
Bresenham Algorithm
List<Point> vertices = new List<Point>();
int deltaX = xN - x0; int signX = deltaX >= 0 ? 1 : -1;
int deltaY = yN - y0; int signY = deltaY >= 0 ? 1 : -1;
if (deltaX == deltaY && deltaX * deltaY == 0) return vertices;
// |dy|/|dx| < 1 => |dy| < |dx| => m < 1
if (Math.Abs(deltaX) > Math.Abs(deltaY))
{
int _2deltaX = deltaX * 2 * signX;
int _2deltaY = deltaY * 2 * signY;
int p0 = _2deltaY - deltaX * signX;
// create array to contain vertices
vertices.Add(new Point(x0, y0));
int xCurrent = x0;
int yCurrent = y0;
while (true)
{
if (count >= (Math.Abs(deltaX) + 1)) return vertices;
if (p0 < 0)
{
xCurrent += signX;
// pk + 1 = pk + 2.∆y.signX
p0 = p0 + _2deltaY;
}
else
{
xCurrent += signX;
yCurrent += signY;
// pk+1= pk + 2.∆y.signX - 2.∆x.signY
p0 = p0 + _2deltaY - _2deltaX;
}
vertices.Add(new Point(xCurrent, yCurrent));
}
}
// |dy|/|dx| > 1 => |dy| > |dx| => m > 1
else if (Math.Abs(deltaX) <= Math.Abs(deltaY))
{
int _2deltaX = deltaX * 2 * signX;
int _2deltaY = deltaY * 2 * signY;
int p0 = _2deltaX - deltaY * signY;
// create array to contain vertices
vertices.Add(new Point(x0, y0));
int xCurrent = x0;
int yCurrent = y0;
while (true)
{
if (count >= (Math.Abs(deltaY) + 1)) return vertices;
if (p0 < 0)
{
yCurrent += signY;
// pk + 1 = pk + 2.∆x.signY
p0 = p0 + _2deltaX;
}
else
{
xCurrent += signX;
yCurrent += signY;
// pk+1= pk + 2.∆x.signY - 2.∆y.signX
p0 = p0 + _2deltaX - _2deltaY;
}
vertices.Add(new Point(xCurrent, yCurrent));
}
}
return vertices;
DDA Algorithm
List<Point> vertices = new List<Point>();
int deltaX = xN - x0; int signX = deltaX >= 0 ? 1 : -1;
int deltaY = yN - y0; int signY = deltaY >= 0 ? 1 : -1;
if (deltaX == deltaY && deltaX * deltaY == 0) return vertices;
int step = Math.Abs(deltaX) > Math.Abs(deltaY) ? Math.Abs(deltaX) : Math.Abs(deltaY);
// x(k + 1) = xk + x'
double stepX = deltaX * 1.0 / step;
double stepY = deltaY * 1.0 / step;
vertices.Add(new Point(x0, y0));
double xCurrent = x0;
double yCurrent = y0;
for (int i = 0; i < step; i++)
{
xCurrent += stepX;
yCurrent += stepY;
vertices.Add(new Point((int)Math.Round(xCurrent), (int)Math.Round(yCurrent)));
}
return vertices;