public static POINTI ToPointC(this XY point)
{
return(POINTI.Ceiling(point.ToPoint()));
}
public static POINTI ToPointR(this XY point)
{
return(POINTI.Round(point.ToPoint()));
}
/// <summary>
/// sets up the SpringGrid springs and points so that it can be drawn
/// </summary>
/// <param name="gridSize"></param>
/// <param name="spacing"></param>
public void SetGridSizeAndSpacing(Rectangle gridSize, System.Numerics.Vector2 spacing)
{
_gridSize = gridSize;
var springList = new List <Spring>();
// we offset the gridSize location by half-spacing so the padding is applied evenly all around
gridSize.Location -= spacing.ToPoint();
gridSize.Width += (int)spacing.X;
gridSize.Height += (int)spacing.Y;
var numColumns = (int)(gridSize.Width / spacing.X) + 1;
var numRows = (int)(gridSize.Height / spacing.Y) + 1;
_points = new PointMass[numColumns, numRows];
// these fixed points will be used to anchor the grid to fixed positions on the screen
var fixedPoints = new PointMass[numColumns, numRows];
// create the point masses
int column = 0, row = 0;
for (float y = gridSize.Top; y <= gridSize.Bottom; y += spacing.Y)
{
for (float x = gridSize.Left; x <= gridSize.Right; x += spacing.X)
{
_points[column, row] = new PointMass(new System.Numerics.Vector3(x, y, 0), 1);
fixedPoints[column, row] = new PointMass(new System.Numerics.Vector3(x, y, 0), 0);
column++;
}
row++;
column = 0;
}
// link the point masses with springs
for (var y = 0; y < numRows; y++)
{
for (var x = 0; x < numColumns; x++)
{
if (x == 0 || y == 0 || x == numColumns - 1 || y == numRows - 1) // anchor the border of the grid
{
springList.Add(new Spring(fixedPoints[x, y], _points[x, y], 0.1f, 0.1f));
}
else if (x % 3 == 0 && y % 3 == 0) // loosely anchor 1/9th of the point masses
{
springList.Add(new Spring(fixedPoints[x, y], _points[x, y], 0.002f, 0.02f));
}
const float stiffness = 0.28f;
const float damping = 0.06f;
if (x > 0)
{
springList.Add(new Spring(_points[x - 1, y], _points[x, y], stiffness, damping));
}
if (y > 0)
{
springList.Add(new Spring(_points[x, y - 1], _points[x, y], stiffness, damping));
}
}
}
_springs = springList.ToArray();
}
public static POINTI ToPointT(this XY point)
{
return(POINTI.Truncate(point.ToPoint()));
}
public static void Translate(ref Rectangle rect, System.Numerics.Vector2 vec)
{
rect.Location += vec.ToPoint();
}
