LÖVE

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love.graphics.translate(dx, dy)
love.graphics.rotate(1.2)
love.graphics.translate(-dx, -dy)

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shear=function(_,a,b)
    if a or b then
        c.a=a or c.a
        c.b=b or c.b
    elseif not (a or b) then
        a=math.abs(c.a)
        b=math.abs(c.b)
        a=(a/(a+45))
        b=(b/(b+45))
        graphics.scale(1-a,1-b)
        graphics.shear(c.a/45,c.b/45)
    end
end

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Rotation Matrix is
cos(r) -sin(r)
sin(r) cos(r)

now when you apply is to an vector
x y
you will get
x*cos(r)-y*sin(r) y*cos(r)+x*sin(r)

Scale Matrix:
S 0
0 S
Shear Matrix is:
1 Sx
Sy 1

Now the Problem is
now when you first apply scale to an vector
x y
you will get 
x*S y*S
now Shear Matrix gives
x*S+y*S*Sx y*S+x*S*Sx

Now remember what we wan't
So first we can replace S with cos(r)
So we will get
x*cos(r)+y*cos(r)*Sx y*cos(r)+x*cos(r)*Sx
Now Sx and is a little bit more complicated
it should be
Sx=-sin(r)/cos(r)
Sy=sin(r)/cos(r)
an we get the rotation function as:
x*cos(r)-y*sin(r) y*cos(r)+x*sin(r)

So we should fill
Scale(cos(r),cos())
Shear(-sin(r)/cos(r),sin()/cos(r))

But now there is a problem
When rotation is 90° cos becomes zero

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local kx, ky = -math.tan(angle/2), math.sin(angle)
love.graphics.shear(kx, 0)
love.graphics.shear(0, ky)
love.graphics.shear(kx, 0)