//------------------------------------------------------------------------
Perspective premultiply(Perspective b)
{
Perspective a = new Perspective(this);
sx = a.sx * b.sx + a.shx * b.shy + a.tx * b.w0;
shx = a.sx * b.shx + a.shx * b.sy + a.tx * b.w1;
tx = a.sx * b.tx + a.shx * b.ty + a.tx * b.w2;
shy = a.shy * b.sx + a.sy * b.shy + a.ty * b.w0;
sy = a.shy * b.shx + a.sy * b.sy + a.ty * b.w1;
ty = a.shy * b.tx + a.sy * b.ty + a.ty * b.w2;
w0 = a.w0 * b.sx + a.w1 * b.shy + a.w2 * b.w0;
w1 = a.w0 * b.shx + a.w1 * b.sy + a.w2 * b.w1;
w2 = a.w0 * b.tx + a.w1 * b.ty + a.w2 * b.w2;
return(this);
}
public ICoordTransformer MultiplyWith(ICoordTransformer another)
{
if (another is Affine)
{
return(this * (Affine)another);
}
else if (another is Perspective)
{
Perspective p = new Perspective(this);
return(p * (Perspective)another);
}
else
{
return(new CoordTransformationChain(this, another));
}
}
ICoordTransformer ICoordTransformer.MultiplyWith(ICoordTransformer another)
{
if (another is Affine)
{
return(this * (Affine)another);
}
else if (another is Perspective)
{
Perspective p = new Perspective(this);
return(p * (Perspective)another);
}
else
{
return(null);
}
}
unsafe bool InternalGenerateQuadToQuad(double *qs_h, double *qdHead)
{
Perspective p = new Perspective();
if (!square_to_quad(qs_h))
{
return(false);
}
invert();
//---------------------------------
if (!p.square_to_quad(qdHead))
{
return(false);
}
multiply(p);
return(true);
}
// From trans_perspective
public Perspective(Perspective a)
{
sx = a.sx; shy = a.shy; w0 = a.w0;
shx = a.shx; sy = a.sy; w1 = a.w1;
tx = a.tx; ty = a.ty; w2 = a.w2;
}