Cfrgtkky

I fails to fill the right-angle mark with green color as follows.

documentclass[12pt]{standalone}

usepackage{pst-eucl,pst-calculate}

begin{document}

begin{pspicture}(-.6,-1)(4.85,4)

defb{3}

pstGeonode[PosAngle={-135,135,-45}](0,0){A}(0,b){B}(pscalculate{b*sqrt(2)},0){D}

pstTranslation[PosAngle=45]{A}{D}{B}[C]

pstMiddleAB{B}{C}{M}

pstInterLL[PointName=none]{A}{C}{M}{D}{E}

pstRightAngle[RightAngleSize=.2,fillstyle=solid,fillcolor=green]{M}{E}{C}

psline(A)(B)(C)(D)(A)(C)(M)(D)

end{pspicture}

end{document}

How to fill a right-angle mark with a color?

If node A is not the origin, then use the coordinate pair {AD,CD} which is {(4,3)} instead of {(C)} for the rotation of rput

documentclass[12pt]{standalone}



usepackage{pst-eucl,pst-calculate}

begin{document}

begin{pspicture}(-.6,-1)(4.85,4)

    defb{3}

    pstGeonode[PosAngle={-135,135,-45}](0,0){A}(0,b){B}(pscalculate{b*sqrt(2)},0){D}

    pstTranslation[PosAngle=45]{A}{D}{B}[C]

    pstMiddleAB{B}{C}{M}

    pstInterLL[PointName=none]{A}{C}{M}{D}{E}

    rput{(C)}(E){psframe[fillcolor=red,fillstyle=solid](0.2,0.2)}%%%%%

    psline(A)(B)(C)(D)(A)(C)(M)(D)

end{pspicture}

end{document}

With pst-eucl.tex from http://archiv.dante.de/~herbert/TeXnik/tex/generic/pst-eucl/ you can use:

pstRightAngle[RightAngleSize=.2,fillstyle=solid,fillcolor=green]{M}{E}{C}

documentclass[pstricks,12pt]{standalone}

usepackage{pst-eucl}

defb{3 }

begin{document}

begin{pspicture}(-.6,-1)(4.85,4)

pstGeonode[PosAngle={-135,135,-45,45}](0,0){A}(!0 b){B}(!b 2 sqrt mul 0){D}(D|B){C}

pstMiddleAB{B}{C}{M}

pstInterLL[PointName=none]{A}{C}{M}{D}{E}

pspolygon[fillstyle=solid,fillcolor=green](E)([nodesep=6pt]{C}E)([offset=6pt,nodesep=6pt]{C}E)([offset=6pt]{C}E)

psline(A)(B)(C)(D)(A)(C)(M)(D)

end{pspicture}

end{document}

Herbert's solution can be generalized by replacing his

rput{(C)}(E){psframe[fillcolor=red,fillstyle=solid](0.2,0.2)}%%%%%

with

pnode(C){c}% temporary 

pnode(E){e}% temporary

rput{!N-c.y N-e.y sub N-c.x N-e.x sub atan}(E){psframe[fillcolor=red,fillstyle=solid](0.2,0.2)}%%%%%

Red alert: the temporary nodes are important and needed because it is one of PSTricks' hidden features. We cannot substitute !N-C.y N-E.y sub N-C.x N-E.x sub atan for !N-c.y N-e.y sub N-c.x N-e.x sub atan.

The complete code is as follows. I translated all points with (1,1) vector just to see a non-trivial effect.

documentclass[12pt]{standalone}



usepackage{pst-eucl,pst-calculate}

begin{document}

begin{pspicture}[saveNodeCoors,showgrid](6,5)

    defb{3}

    pstGeonode[PosAngle={-135,135,-45}](1,1){A}(1,pscalculate{b+1}){B}(pscalculate{b*sqrt(2)+1},1){D}

    pstTranslation[PosAngle=45]{A}{D}{B}[C]

    pstMiddleAB{B}{C}{M}

    pstInterLL[PointName=none]{A}{C}{M}{D}{E}

    pnode(C){c}% temporary 

    pnode(E){e}% temporary

    rput{!N-c.y N-e.y sub N-c.x N-e.x sub atan}(E){psframe[fillcolor=red,fillstyle=solid](0.2,0.2)}%%%%%

    psline(A)(B)(C)(D)(A)(C)(M)(D)

end{pspicture}

end{document}