| public Rotate ( float angle, float x0, float y0 ) : bool | ||
| angle | float | |
| x0 | float | |
| y0 | float | |
| return | bool | |
public bool Rotate(float angle, float x0, float y0)
{
float3 unity = new float3(new float2(x0, y0));
unity.Unit();
fTransformMatrix = float3x3.Rotate(angle, unity);
XFORM xm = new XFORM();
Translate(-x0, -y0); // make (x0,y0) the origin
double rad = angle * (Math.PI / 180);
xm.eM11 = (float)Math.Cos(rad);
xm.eM12 = (float)Math.Sin(rad);
xm.eM21 = -xm.eM12;
xm.eM22 = xm.eM11;
xm.eDx = 0;
xm.eDy = 0;
Combine(xm); // rotate
Translate(x0, y0); // move origin back
return true;
}
