Htydjtk

I want to achieve 3D effect in my picture. This is to show Electron beam lithography followed by lift-off process. I want to make a cross shaped hole in the top layer and fill it with a gray color material till half. How to achieve this with opacity and shading?

Thanks

    documentclass[pdf]{beamer}

    mode<presentation>{usetheme{Warsaw}} 

    usepackage{animate}

    usepackage{amsmath}

    usepackage{tikz}

    title{My Presentation}

    author[Raghuram Dharmavarapu]{Raghu}

    date{}



    usetikzlibrary{arrows,snakes,shapes,fadings}

begin{document}

begin{frame}[fragile,t]

frametitle{Fabrication of Metasurface}

hspace{-0.5cm}

begin{minipage}{0.44textwidth}

underline{Fabrication flow:}

vspace{0.5cm}

fontsize{10pt}{14pt}

begin{enumerate}

item<1-> only<1>{color{red!70!black}}Glass substrate

item<2-> only<2>{color{red!70!black}}Resist spin-coating

item<3-> only<3>{color{red!70!black}}Electron beam Lithography

item<4-> only<4>{color{red!70!black}}Development

item<5-> only<5>{color{red!70!black}}RF Sputtering(Silicon)

item<6-> only<6>{color{red!70!black}}Lift-Off

end{enumerate}

end{minipage}

begin{minipage}{0.55textwidth}

begin{tikzpicture}[scale = 0.74]

onslide<1->

    useasboundingbox (0.5,0) rectangle (10,8);

    filldraw[blue!40!black] (1.5,1) -- (9.5,1) -- (9.75,1.5) --(1.25,1.5)--cycle;

    shade[top color = blue!40!white, bottom color = blue!40!white!70] (1.25,1.5) --(9.75,1.5) -- (8,3.7) -- (3,3.7) --cycle;



onslide<2,3,4,5>

filldraw[blue!60!green,opacity = 0.6] (1.25,1.5) rectangle (9.75,1.75);

shade[top color = blue!60!green!70, bottom color = blue!60!green!70,opacity = 0.6] (1.25,1.75) --(9.75,1.75) -- (8.03,3.81) -- (2.97,3.81) --cycle;



onslide<3,4>

begin{scope}[shift = {(3,4)}]

shade[inner color=red!70!black, top color=red!75!white] (2.2,1.8)

    -- ++(0.6,0) -- ++(-0.3,-1.8) -- cycle;

  shade[left color=gray!50!white,right color=gray] (1.7,3)

    -- ++(1.6,0) -- ++(-0.3,-1) -- ++(-1,0) -- cycle;

  shade[left color=gray!50!white,right color=gray] (2.1,2)

    -- ++(0.8,0) -- ++(0,-0.2) -- ++(-0.8,0) -- cycle;

  draw[gray!80!black] (1.7,3) -- ++(1.6,0) -- ++(-0.3,-1)

    -- ++(-1,0) -- cycle;

  draw[gray!80!black] (2.1,2) -- ++(0,-0.2) -- ++(0.8,0)

    -- ++(0,0.2);

  node[thick,red!70!black] at ( -0,2) {footnotesize Electron Gun};

end{scope}

onslide<4>

foreach x/y in {0/0,0.7/0.5,-0.7/-0.5, -1/0, 1/0,0.7/-0.5,-0.7/0.5,0/0.7,0/-0.7}

{

begin{scope}[shift = {(4.5+x,1.4+y)},scale = 1,opacity = 1]

     clip[scale = 0.08,postaction={fill=blue!40!black}] 

     (11,16-2) -- (14,16-2) -- (13.9,17-2) 

     -- (15.5,17-2) --(15.2,18.25-2)

     --(13.7,18.25-2)--(13.6,19-2)--

     (11.4,19-2)--(11.3,18.25-2)--(9.8,18.25-2)

     --(9.5,17-2)--(11.1,17-2)--cycle;

     fill[blue,scale = 0.08] (9.8,18.25-3) --(9.8,18.25-2)

     --(9.5,17-2) --(9.5,17-3);

     filldraw[blue!60!white,scale = 0.08] (11.3,18.25-2) -- (11.3,18.25-3)

     --(9.8,18.25-3) --(9.8,18.25-2);

     fill[blue,scale = 0.08] (11.3,18.25-2) -- (11.3,18.25-3)

     --(11.4,19-3) --(11.4,19-2);

     filldraw[blue!60!white,scale = 0.08] (11.4,19-2) --(13.6,19-2) --(13.6,19-3) -- (11.4,19-3);

     fill[blue!60!green!70,scale = 0.08]

     (13.6,19-2) --(13.7,18.25-2) --(13.7,18.25-3) --(13.6,19-3);

     filldraw[blue!60!white,scale = 0.08]

     (13.7,18.25-2) --(15.2,18.25-2) --(15.2,18.25-3)

     --(13.7,18.25-3);

     fill[blue!60!green!70,scale = 0.08]

     (15.2,18.25-2) --(15.2,18.25-3)--(15.5,17-3)--(15.5,17-2);

end{scope}

}



onslide<5>

foreach x/y in {0/0,0.7/0.5,-0.7/-0.5, -1/0, 1/0,0.7/-0.5,-0.7/0.5,0/0.7,0/-0.7}

{

begin{scope}[shift = {(4.5+x,1.4+y)},scale = 1,opacity = 1]

     clip[scale = 0.08,postaction={fill=black!30!white}] 

     (11,16-2) -- (14,16-2) -- (13.9,17-2) 

     -- (15.5,17-2) --(15.2,18.25-2)

     --(13.7,18.25-2)--(13.6,19-2)--

     (11.4,19-2)--(11.3,18.25-2)--(9.8,18.25-2)

     --(9.5,17-2)--(11.1,17-2)--cycle;

     fill[blue,scale = 0.08] (9.8,18.25-3) --(9.8,18.25-2)

     --(9.5,17-2) --(9.5,17-3);

     filldraw[blue!60!white,scale = 0.08,draw = blue!70!white ] (11.3,18.25-2) -- (11.3,18.25-3) --(9.8,18.25-3) --(9.8,18.25-2);

5     fill[blue,scale = 0.08] (11.3,18.25-2) -- (11.3,18.25-3)

     --(11.4,19-3) --(11.4,19-2);

     filldraw[blue!60!white,scale = 0.08,draw = blue!70!white ] (11.4,19-2) --(13.6,19-2) --(13.6,19-3) -- (11.4,19-3);

     fill[blue!60!green!70,scale = 0.08]

     (13.6,19-2) --(13.7,18.25-2) --(13.7,18.25-3) --(13.6,19-3);

     filldraw[blue!60!white,scale = 0.08,draw = blue!70!white ]

     (13.7,18.25-2) --(15.2,18.25-2) --(15.2,18.25-3)

     --(13.7,18.25-3);

     fill[blue!60!green!70,scale = 0.08,draw = blue!70!white ]

     (15.2,18.25-2) --(15.2,18.25-3)--(15.5,17-3)--(15.5,17-2);

end{scope}

}

filldraw[bottom color = gray!20!white, top color = gray!80!white] (4.75,6.5) rectangle (6.25,6.75);

filldraw[orange!80!black,rotate = 50, shift = {(0.3,-8.5)}] (8,4.5) rectangle (8.25,3);

draw[thick,orange,->,densely dashed] (8.5,3.85) -- (5,6.5);

draw[thick,orange,->,densely dashed] (8.5,3.85) -- (5.5,6.5);

draw[thick,orange,->,densely dashed] (8.5,3.85) -- (6,6.5);

node[thick,red!70!black] at (9.25,4.25) {footnotesize Ions};

foreach x/y in {0/0,0.5/-0.5,-0.8/-1,0.8/-1.5,-1.5/-0.8,-2.1/-3,-1.5/-4,1.4/-4.2,

0/-5,2/-3.5,-0.2/-3.2,0.4/-2.1,-1/-5.5,0.9/-5.1,-3/-6,-3.5/-7.2,

-0.5/-5.6,2.7/-6.2,0/-7.5}

{

node[circle,shading=ball,minimum size=0.1mm,scale = 0.3,ball color = gray!80,shift = {(x,y)}] (ball) at (5.5,6.25) {};

}

node[red!80!black] at (8,6.675) {footnotesize Silicon target} ;

onslide<6->

foreach x/y in {0/0,0.7/0.5,-0.7/-0.5, -1/0, 1/0,0.7/-0.5,-0.7/0.5,0/0.7,0/-0.7}

{

begin{scope}[shift = {(4.5+x,1.4+y)},scale = 1,opacity = 1]

    filldraw[gray!30!white,scale = 0.08] (11,16) -- (14,16) -- (13.9,17) -- (15.5,17) --(15.2,18.25)--(13.7,18.25)--(13.6,19)--(11.4,19)--(11.3,18.25)--(9.8,18.25)--(9.5,17)--(11.1,17)--cycle;

    filldraw[gray!90!white,scale = 0.08] (9.5,17)--(9.6,15.5)--(11.05,15.5)--(11,16)--(11.1,17)--cycle;

    filldraw[gray!90!black,scale = 0.08] (11,16) -- (11.1,15) -- (13.9,15) -- (14,16)-- cycle;

    filldraw[gray!90!white,scale = 0.08] (15.5,17) --(15.4,15.5) --(13.95,15.5) --(14,16) -- (13.9,17) --cycle;

end{scope}

}

onslide<1->

end{tikzpicture}

end{minipage}

end{frame}



end{document}

EDIT

I was able to achieve what I wanted shown in below figure. But when I actually copied it into my main tex file it is behaving strangely, it is showing comingup onslide material in white color over existing slides. I was using setbeamercovered in one of my slides in my main tex file. If I remove that slide its working perfectly but when I include it it is causing problem like shown below.

Working solution in separate text file.

When copied into main text it is giving output as

EDIT

I solved it by using setbeamercovered{invisible} command.

You could do something like this:

documentclass[pdf]{beamer}

mode<presentation>{usetheme{Warsaw}} 

usepackage{animate}

usepackage{amsmath}

usepackage{tikz}

title{My Presentation}

author[Raghuram Dharmavarapu]{Raghu}

date{}



usetikzlibrary{arrows,snakes,shapes,fadings}

begin{document}

   begin{frame}

frametitle{Fabrication of Metasurface}

begin{tikzpicture}[scale = 1]

onslide<1->

    useasboundingbox (0,0) rectangle (10,8);

    begin{scope}

    filldraw[blue!40!black] (1.5,1) -- (9.5,1) -- (9.75,1.5) --(1.25,1.5)--cycle;

    shade[top color = blue!40!white, bottom color = blue!40!white!70] (1.25,1.5) --(9.75,1.5) -- (8,3.5) -- (3,3.5) --cycle;

    end{scope}



onslide<2->

filldraw[blue!60!green,opacity = 0.6] (1.25,1.5) rectangle (9.75,1.75);

 shade[top color = blue!60!green!70, bottom color = blue!60!green!70,opacity = 0.6] (1.25,1.75) --(9.75,1.75) -- (8.03,3.61) -- (2.97,3.61) --cycle;



onslide<3>

begin{scope}[shift = {(3,4)}]

shade[inner color=red!70!black, top color=red!75!white] (2.2,1.8)

    -- ++(0.6,0) -- ++(-0.3,-1.8) -- cycle;

  shade[left color=gray!50!white,right color=gray] (1.7,3)

    -- ++(1.6,0) -- ++(-0.3,-1) -- ++(-1,0) -- cycle;

  shade[left color=gray!50!white,right color=gray] (2.1,2)

    -- ++(0.8,0) -- ++(0,-0.2) -- ++(-0.8,0) -- cycle;

  draw[gray!80!black] (1.7,3) -- ++(1.6,0) -- ++(-0.3,-1)

    -- ++(-1,0) -- cycle;

  draw[gray!80!black] (2.1,2) -- ++(0,-0.2) -- ++(0.8,0)

    -- ++(0,0.2);

end{scope}

onslide<4->

begin{scope}[shift = {(1,-1.3)},scale = 3,opacity = 1]

%     filldraw[gray!50!white,scale = 0.08] (11,16) -- (14,16) -- (13.9,17) -- (15.5,17) --(15.2,18.25)--(13.7,18.25)--(13.6,19)--(11.4,19)--(11.3,18.25)--(9.8,18.25)--(9.5,17)--(11.1,17)--cycle;

% 

% 

%      filldraw[gray!70!white,scale = 0.08] (11,16) -- (14,16) -- (13.9,17) -- (13.7,18.25)--(11.3,18.25)--(11.1,17)--cycle;

%      filldraw[blue!60!green!70,scale = 0.08] (9.5,17)--(9.6,14.5)--(11.05,14.5)--(11,16)--(11.1,17)--cycle;

%     filldraw[blue!60!green,scale = 0.08] (11,16) -- (11.1,14) -- (13.9,14) -- (14,16)-- cycle;

%     filldraw[blue!60!green!70,scale = 0.08] (15.5,17) --(15.4,14.5) --(13.95,14.5) --(14,16) -- (13.9,17) --cycle;



     clip[scale = 0.08,postaction={fill=blue!40!black}] 

     (11,16-2) -- (14,16-2) -- (13.9,17-2) 

     -- (15.5,17-2) --(15.2,18.25-2)

     --(13.7,18.25-2)--(13.6,19-2)--

     (11.4,19-2)--(11.3,18.25-2)--(9.8,18.25-2)

     --(9.5,17-2)--(11.1,17-2)--cycle;

     fill[blue,scale = 0.08] (9.8,18.25-3) --(9.8,18.25-2)

     --(9.5,17-2) --(9.5,17-3);

     filldraw[blue!60!white,scale = 0.08] (11.3,18.25-2) -- (11.3,18.25-3)

     --(9.8,18.25-3) --(9.8,18.25-2);

     fill[blue,scale = 0.08] (11.3,18.25-2) -- (11.3,18.25-3)

     --(11.4,19-3) --(11.4,19-2);

     filldraw[blue!60!white,scale = 0.08] (11.4,19-2) --(13.6,19-2) --(13.6,19-3) -- (11.4,19-3);

     fill[blue!60!green!70,scale = 0.08]

     (13.6,19-2) --(13.7,18.25-2) --(13.7,18.25-3) --(13.6,19-3);

     filldraw[blue!60!white,scale = 0.08]

     (13.7,18.25-2) --(15.2,18.25-2) --(15.2,18.25-3)

     --(13.7,18.25-3);

     fill[blue!60!green!70,scale = 0.08]

     (15.2,18.25-2) --(15.2,18.25-3)--(15.5,17-3)--(15.5,17-2);

end{scope}

end{tikzpicture}

end{frame}

end{document}

However, I would really like to draw your attention to this great answer, which allows you to draw things in 3d perspective. If I was you, I would redraw your diagram with these tools.

documentclass[pdf]{beamer}

mode<presentation>{usetheme{Warsaw}} 

usepackage{animate}

usepackage{amsmath}

usepackage{tikz}

usepackage{tikz-3dplot}

usetikzlibrary{overlay-beamer-styles}

usepgfmodule{nonlineartransformations}

% Max magic

makeatletter 

% the first part is not in use here

deftikz@scan@transform@one@point#1{%

  tikz@scan@one@pointpgf@process#1%

  pgf@pos@transform{pgf@x}{pgf@y}}

tikzset{%

  grid source opposite corners/.code args={#1and#2}{%

   pgfextract@processtikz@transform@source@southwest{%

     tikz@scan@transform@one@point{#1}}%

   pgfextract@processtikz@transform@source@northeast{%

     tikz@scan@transform@one@point{#2}}%

  },

  grid target corners/.code args={#1--#2--#3--#4}{%

   pgfextract@processtikz@transform@target@southwest{%

     tikz@scan@transform@one@point{#1}}%

   pgfextract@processtikz@transform@target@southeast{%

     tikz@scan@transform@one@point{#2}}%

   pgfextract@processtikz@transform@target@northeast{%

     tikz@scan@transform@one@point{#3}}%

   pgfextract@processtikz@transform@target@northwest{%

     tikz@scan@transform@one@point{#4}}%

  }

}



deftikzgridtransform{%

  pgfextract@processtikz@current@point{}%

  pgf@process{%

    pgfpointdiff{tikz@transform@source@southwest}%

      {tikz@transform@source@northeast}%

  }%

  pgf@xc=pgf@xpgf@yc=pgf@y%

  pgf@process{%

    pgfpointdiff{tikz@transform@source@southwest}{tikz@current@point}%

  }%

  pgfmathparse{pgf@x/pgf@xc}lettikz@tx=pgfmathresult%

  pgfmathparse{pgf@y/pgf@yc}lettikz@ty=pgfmathresult%

  %

  pgfpointlineattime{tikz@ty}{%

    pgfpointlineattime{tikz@tx}{tikz@transform@target@southwest}%

      {tikz@transform@target@southeast}}{%

    pgfpointlineattime{tikz@tx}{tikz@transform@target@northwest}%

      {tikz@transform@target@northeast}}%

}



% Initialize H matrix for perspective view

pgfmathsetmacroH@tpp@aa{1}pgfmathsetmacroH@tpp@ab{0}pgfmathsetmacroH@tpp@ac{0}%pgfmathsetmacroH@tpp@ad{0}

pgfmathsetmacroH@tpp@ba{0}pgfmathsetmacroH@tpp@bb{1}pgfmathsetmacroH@tpp@bc{0}%pgfmathsetmacroH@tpp@bd{0}

pgfmathsetmacroH@tpp@ca{0}pgfmathsetmacroH@tpp@cb{0}pgfmathsetmacroH@tpp@cc{1}%pgfmathsetmacroH@tpp@cd{0}

pgfmathsetmacroH@tpp@da{0}pgfmathsetmacroH@tpp@db{0}pgfmathsetmacroH@tpp@dc{0}%pgfmathsetmacroH@tpp@dd{1}



%Initialize H matrix for main rotation

pgfmathsetmacroH@rot@aa{1}pgfmathsetmacroH@rot@ab{0}pgfmathsetmacroH@rot@ac{0}%pgfmathsetmacroH@rot@ad{0}

pgfmathsetmacroH@rot@ba{0}pgfmathsetmacroH@rot@bb{1}pgfmathsetmacroH@rot@bc{0}%pgfmathsetmacroH@rot@bd{0}

pgfmathsetmacroH@rot@ca{0}pgfmathsetmacroH@rot@cb{0}pgfmathsetmacroH@rot@cc{1}%pgfmathsetmacroH@rot@cd{0}

%pgfmathsetmacroH@rot@da{0}pgfmathsetmacroH@rot@db{0}pgfmathsetmacroH@rot@dc{0}pgfmathsetmacroH@rot@dd{1}



pgfkeys{

    /three point perspective/.cd,

        p/.code args={(#1,#2,#3)}{

            pgfmathparse{int(round(#1))}

            ifnumpgfmathresult=0else

                pgfmathsetmacroH@tpp@ba{#2/#1}

                pgfmathsetmacroH@tpp@ca{#3/#1}

                pgfmathsetmacroH@tpp@da{ 1/#1}

                coordinate (vp-p) at (#1,#2,#3);

            fi

        },

        q/.code args={(#1,#2,#3)}{

            pgfmathparse{int(round(#2))}

            ifnumpgfmathresult=0else

                pgfmathsetmacroH@tpp@ab{#1/#2}

                pgfmathsetmacroH@tpp@cb{#3/#2}

                pgfmathsetmacroH@tpp@db{ 1/#2}

                coordinate (vp-q) at (#1,#2,#3);

            fi

        },

        r/.code args={(#1,#2,#3)}{

            pgfmathparse{int(round(#3))}

            ifnumpgfmathresult=0else

                pgfmathsetmacroH@tpp@ac{#1/#3}

                pgfmathsetmacroH@tpp@bc{#2/#3}

                pgfmathsetmacroH@tpp@dc{ 1/#3}

                coordinate (vp-r) at (#1,#2,#3);

            fi

        },

        coordinate/.code args={#1,#2,#3}{

           pgfmathsetmacrotpp@x{#1} %<- Max' fix

            pgfmathsetmacrotpp@y{#2}

            pgfmathsetmacrotpp@z{#3}

        },

}



tikzset{

    view/.code 2 args={

        pgfmathsetmacrorot@main@theta{#1}

        pgfmathsetmacrorot@main@phi{#2}

        % Row 1

        pgfmathsetmacroH@rot@aa{cos(rot@main@phi)}

        pgfmathsetmacroH@rot@ab{sin(rot@main@phi)}

        pgfmathsetmacroH@rot@ac{0}

        % Row 2

        pgfmathsetmacroH@rot@ba{-cos(rot@main@theta)*sin(rot@main@phi)}

        pgfmathsetmacroH@rot@bb{cos(rot@main@phi)*cos(rot@main@theta)}

        pgfmathsetmacroH@rot@bc{sin(rot@main@theta)}

        % Row 3

        pgfmathsetmacroH@m@ca{sin(rot@main@phi)*sin(rot@main@theta)}

        pgfmathsetmacroH@m@cb{-cos(rot@main@phi)*sin(rot@main@theta)}

        pgfmathsetmacroH@m@cc{cos(rot@main@theta)}

        % Set vector values

        pgfmathsetmacrovec@x@x{H@rot@aa}

        pgfmathsetmacrovec@y@x{H@rot@ab}

        pgfmathsetmacrovec@z@x{H@rot@ac}

        pgfmathsetmacrovec@x@y{H@rot@ba}

        pgfmathsetmacrovec@y@y{H@rot@bb}

        pgfmathsetmacrovec@z@y{H@rot@bc}

        % Set pgf vectors

        pgfsetxvec{pgfpoint{vec@x@x cm}{vec@x@y cm}}

        pgfsetyvec{pgfpoint{vec@y@x cm}{vec@y@y cm}}

        pgfsetzvec{pgfpoint{vec@z@x cm}{vec@z@y cm}}

    },

}



tikzset{

    perspective/.code={pgfkeys{/three point perspective/.cd,#1}},

    perspective/.default={p={(15,0,0)},q={(0,15,0)},r={(0,0,50)}},

}



tikzdeclarecoordinatesystem{three point perspective}{

    pgfkeys{/three point perspective/.cd,coordinate={#1}}

    pgfmathsetmacrotemp@p@w{H@tpp@da*tpp@x + H@tpp@db*tpp@y + H@tpp@dc*tpp@z + 1}

    pgfmathsetmacrotemp@p@x{(H@tpp@aa*tpp@x + H@tpp@ab*tpp@y + H@tpp@ac*tpp@z)/temp@p@w}

    pgfmathsetmacrotemp@p@y{(H@tpp@ba*tpp@x + H@tpp@bb*tpp@y + H@tpp@bc*tpp@z)/temp@p@w}

    pgfmathsetmacrotemp@p@z{(H@tpp@ca*tpp@x + H@tpp@cb*tpp@y + H@tpp@cc*tpp@z)/temp@p@w}

    pgfpointxyz{temp@p@x}{temp@p@y}{temp@p@z}

}

tikzaliascoordinatesystem{tpp}{three point perspective}



makeatother

tikzset{set mark/.style args={#1|#2}{

postaction={decorate,decoration={markings,

mark=at position #1 with {coordinate(#2);}}}}}

title{My Presentation}

author[Raghuram Dharmavarapu]{Raghu}

date{}



usetikzlibrary{shapes,fadings}

begin{document}

foreach X in {0,0.08,...,0.8,0.72,0.64,...,0}

{begin{frame}[t]

frametitle{Fabrication of Metasurface}

tdplotsetmaincoords{77}{0}

pgfmathsetmacro{vq}{5}

begin{tikzpicture}[scale=pi,%tdplot_main_coords

  view={tdplotmaintheta}{tdplotmainphi},

            perspective={

                p = {(0,0,10)},

                q = {(0,vq,1.25)},

            }

  ]

  path[tdplot_screen_coords] (-1.5,0.1) rectangle (1.5,2.7);

  filldraw[blue!40!black]

   (tpp cs:-1,-1,1)  -- (tpp cs:1,-1,1)

   -- (tpp cs:0.9,-0.9,0.8) -- (tpp cs:-0.9,-0.9,0.8) -- cycle;

  shade[top color = blue!40!white, bottom color = blue!40!white!70] 

  (tpp cs:-1,-1,1)  -- (tpp cs:1,-1,1) -- (tpp cs:1,1,1) -- (tpp cs:-1,1,1) 

  -- cycle;

  %onslide<2->

  begin{scope}

   filldraw[blue!60!green,opacity = 0.6] 

   (tpp cs:-1,-1,1)  -- (tpp cs:1,-1,1)

   -- (tpp cs:1,-1,1.1) -- (tpp cs:-1,-1,1.1)  -- cycle;

   shade[top color = blue!60!green!70, bottom color = blue!60!green!70,opacity = 0.6] 

    (tpp cs:-1,-1,1.1)  -- (tpp cs:1,-1,1.1) -- (tpp cs:1,1,1.1) -- (tpp cs:-1,1,1.1) 

    -- cycle;

  end{scope}

  %onslide<3->

  begin{scope}[tdplot_screen_coords,shift={(-0.75,1.5)},scale=0.3]

  shade[inner color=red!70!black, top color=red!75!white] (2.2,1.8)

    -- ++(0.6,0) -- ++(-0.3,-1.8) -- cycle;

  shade[left color=gray!50!white,right color=gray] (1.7,3)

    -- ++(1.6,0) -- ++(-0.3,-1) -- ++(-1,0) -- cycle;

  shade[left color=gray!50!white,right color=gray] (2.1,2)

    -- ++(0.8,0) -- ++(0,-0.2) -- ++(-0.8,0) -- cycle;

  draw[gray!80!black] (1.7,3) -- ++(1.6,0) -- ++(-0.3,-1)

    -- ++(-1,0) -- cycle;

  draw[gray!80!black] (2.1,2) -- ++(0,-0.2) -- ++(0.8,0)

    -- ++(0,0.2);

  end{scope}

  %onslide<4->

  begin{scope}

   defmyx{X}

   clip[postaction={fill=blue!40!black}]   (tpp cs:myx-0.1,-0.4,1.1)

   -- (tpp cs:myx-0.3,-0.4,1.1)   

   -- (tpp cs:myx-0.3,-0.2,1.1)

   -- (tpp cs:myx-0.5,-0.2,1.1)

   -- (tpp cs:myx-0.5,-0.4,1.1)

   -- (tpp cs:myx-0.7,-0.4,1.1)

   -- (tpp cs:myx-0.7,-0.6,1.1)

   -- (tpp cs:myx-0.5,-0.6,1.1)

   -- (tpp cs:myx-0.5,-0.8,1.1)

   -- (tpp cs:myx-0.3,-0.8,1.1)

   -- (tpp cs:myx-0.3,-0.6,1.1)

   -- (tpp cs:myx-0.1,-0.6,1.1)

   -- cycle;

   fill[blue!50] (tpp cs:myx-0.3,-0.2,1) -- (tpp cs:myx-0.3,-0.2,1.1)

   -- (tpp cs:myx-0.5,-0.2,1.1) -- (tpp cs:myx-0.5,-0.2,1)

   -- cycle; % 1

   fill[blue!60!green!70] (tpp cs:myx-0.3,-0.4,1.1) -- (tpp cs:myx-0.3,-0.4,1) 

   -- (tpp cs:myx-0.3,-0.2,1) -- (tpp cs:myx-0.3,-0.2,1.1)

   -- cycle; % 2

   fill[blue!50!black] (tpp cs:myx-0.5,-0.2,1.1) -- (tpp cs:myx-0.5,-0.2,1)

    -- (tpp cs:myx-0.5,-0.4,1) -- (tpp cs:myx-0.5,-0.4,1.1)

   -- cycle; % 2

   fill[blue!50] (tpp cs:myx-0.1,-0.4,1.1)

   -- (tpp cs:myx-0.3,-0.4,1.1) -- (tpp cs:myx-0.3,-0.4,1) -- (tpp cs:myx-0.1,-0.4,1)

   -- cycle; % 3 

   fill[blue!50]  (tpp cs:myx-0.5,-0.4,1) -- (tpp cs:myx-0.5,-0.4,1.1)

   -- (tpp cs:myx-0.7,-0.4,1.1) -- (tpp cs:myx-0.7,-0.4,1)

   -- cycle; % 3

   fill[blue!60!green!70] (tpp cs:myx-0.1,-0.4,1.1)

   -- (tpp cs:myx-0.1,-0.6,1.1) -- (tpp cs:myx-0.1,-0.6,1) -- (tpp cs:myx-0.1,-0.4,1)

   -- cycle; % 4

   fill[blue!50!black]  (tpp cs:myx-0.7,-0.4,1.1) -- (tpp cs:myx-0.7,-0.4,1)

   -- (tpp cs:myx-0.7,-0.6,1) -- (tpp cs:myx-0.7,-0.6,1.1)

   -- cycle; % 4

   fill[blue!60!green!70] (tpp cs:myx-0.3,-0.8,1.1) -- (tpp cs:myx-0.3,-0.8,1) 

   -- (tpp cs:myx-0.3,-0.6,1) -- (tpp cs:myx-0.3,-0.6,1.1)

   -- cycle; % 5

   fill[blue!50!black] (tpp cs:myx-0.5,-0.6,1.1) -- (tpp cs:myx-0.5,-0.6,1)

    -- (tpp cs:myx-0.5,-0.8,1) -- (tpp cs:myx-0.5,-0.8,1.1)

   -- cycle; % 5

  end{scope}

end{tikzpicture}

end{frame}}

end{document}

This is to illustrate the advantage of Max' great code: you draw in 3d, and TikZ will compute the perspective projection for you.