public T_Viewport(SizeF sourceSize, Vector2D sourceUnits,
SizeF targetSize, Vector2D targetUnits,
Rotation targetRotation)
{
this.sourceSize = sourceSize;
this.sourceUnits = sourceUnits;
this.targetSize = targetSize;
this.targetUnits = targetUnits;
this.targetRotation = targetRotation;
// create 2D scaling & rotation & axis reflection
var normalizedTargetSize = Matrix2x2.RotationMatrix(targetRotation.ReverseRotation()) * targetSize;
float mx = normalizedTargetSize.Width / sourceSize.Width;
float my = normalizedTargetSize.Height / sourceSize.Height;
var reflection = Matrix2x2.Unit();
if (targetUnits.x * sourceUnits.x < 0)
{
reflection.x1y1 = -1;
}
if (targetUnits.y * sourceUnits.y < 0)
{
reflection.x2y2 = -1;
}
Matrix2x2 scaleRotateReflect = new Matrix2x2(mx, 0, 0, my) * Matrix2x2.RotationMatrix(targetRotation) * reflection;
// combine with translation into a 3D matrix
m = new Matrix3x3(scaleRotateReflect);
if (m.x1y1 < 0)
{
m.x3y1 = normalizedTargetSize.Width;
}
if (m.x1y2 < 0)
{
m.x3y2 = normalizedTargetSize.Width;
}
if (m.x2y1 < 0)
{
m.x3y1 = normalizedTargetSize.Height;
}
if (m.x2y2 < 0)
{
m.x3y2 = normalizedTargetSize.Height;
}
}
public static Matrix2x2 RotationMatrix(Rotation rotation, float unit = 1f)
{
switch (rotation)
{
case Rotation.Rotate90:
return(new Matrix2x2(0f, -unit, unit, 0f));
case Rotation.Rotate180:
return(new Matrix2x2(-unit, 0f, 0f, -unit));
case Rotation.Rotate270:
return(new Matrix2x2(0f, unit, -unit, 0f));
default:
break;
}
return(Matrix2x2.Unit(unit));
}