Clear[D1, D2, D3, e, f, a, b, c, g, T3]
D1[t_] := 
      Show[Graphics[{RGBColor[1, 1, 0], 
            Polygon[{{-t, 0}, {-t, 1}, {1 - t, 1}, {1 - t, 0}}]}], 
        DisplayFunction -> Identity]
D2[t_] := 
      Show[Graphics[{RGBColor[0, 1, 1], 
            Polygon[{{0, 0}, {1, 0}, {1, 1}, {0, 1}}]}], 
        DisplayFunction -> Identity]
D3[t_] := 
      Show[Graphics[{RGBColor[0, 1, 0], Polygon[{{0, 0}, {1, 0}}]}], 
          DisplayFunction -> Identity] /; -1 > 
          t
D3[t_] := 
      Show[Graphics[{RGBColor[0, 1, 0], 
              Polygon[{{1, 0}, {1, 1}, {-t, 1}, {-t, 0}}]}], 
          DisplayFunction -> Identity] /; -1 ≤ 
          t ≤ 0
D3[t_] := 
      Show[Graphics[{RGBColor[0, 1, 0], 
              Polygon[{{0, 0}, {0, 1}, {1 - t, 1}, {1 - t, 0}}]}], 
          DisplayFunction -> Identity] /; 
        0 ≤ t ≤ 1
D3[t_] := 
      Show[Graphics[{RGBColor[0, 1, 0], Polygon[{{1, 0}, {1, 1}}]}], 
          DisplayFunction -> Identity] /; 
        t > 1
e[x_] := 
      Show[{D1[t], D2[t], D3[t]}, 
        PlotRange -> {{-3, 3}, {-0.5, 1.5}}, Axes -> True, 
        AxesLabel -> {"u", t}, AspectRatio -> Automatic,  
        ImageSize ->  {600, 400}, 
        DisplayFunction -> Identity]

    
f[t_] := 
      1 + t /; -1 ≤ t ≤ 
          0
f[t_] := 
      1 - t /; 0 ≤ t ≤ 1
f[t_] := 0 /; t < -1 || t > 1
a[t_] := 
      Plot[f[x], {x, -10, t}, 
        PlotStyle -> {RGBColor[0, 1, 0], Thickness[0.008]}, 
        DisplayFunction -> Identity]
b[t_] := 
      Show[Graphics[{RGBColor[0, 1, 0], PointSize[0.05], Point[{t, f[t]}]}], 
        DisplayFunction -> Identity]
T3[t_] := 
      Show[Graphics[{RGBColor[0, 1, 0], Polygon[{{0, 0}}]}], 
          DisplayFunction -> Identity] /; -1 > 
          t
T3[t_] := 
      Show[Graphics[{RGBColor[0, 1, 0], 
              Polygon[{{-1, 0}, {t, t + 1}, {t, 0}}]}], 
          DisplayFunction -> Identity] /; -1 ≤ 
          t ≤ 0
T3[t_] := 
      Show[Graphics[{RGBColor[0, 1, 0], 
              Polygon[{{-1, 0}, {0, 1}, {t, 1 - t}, {t, 0}}]}], 
          DisplayFunction -> Identity] /; 
        0 ≤ t ≤ 1
T3[t_] := 
      Show[Graphics[{RGBColor[0, 1, 0], 
              Polygon[{{-1, 0}, {0, 1}, {1, 0}}]}], 
          DisplayFunction -> Identity] /; t > 1

    
c[t_] := 
      Show[a[t], T3[t], PlotRange -> {{-3, 3}, {-0.5, 1.5}}, 
        AspectRatio -> Automatic, 
        AxesLabel -> {"t", "c(t)"},  
        ImageSize ->  {600, 400}, 
        DisplayFunction -> 
          Identity]

correlation = 
      Table[Show[GraphicsArray[{{e[t]}, {c[t]}}], 
          DisplayFunction -> $DisplayFunction,  
          ImageSize ->  {600, 400}], {t, -3, 3, 
          0.1}]

\(Export["correlation.avi", 
      correlation]






\)