tikz.dev / tkz-euclide Manual

tkz-euclide

Complements

39 The Show

39.1 Show the constructions of some lines \tkzShowLine
  • \tkzShowLine[⟨local options⟩](⟨pt1,pt2⟩) or (⟨pt1,pt2,pt3⟩)

  • These constructions concern mediators (perpendicular bisectors), perpendicular or parallel lines through a given point, and bisectors. The arguments are therefore lists of two or three points. Several options adjust the constructions. The idea of this macro comes from Yves Combe.

    optionsdefaultdefinition
    mediatormediatordisplays the constructions of a mediator
    perpendicularmediatorconstructions for a perpendicular
    orthogonalmediatoridem
    bisectormediatorconstructions for a bisector
    K1circle within a triangle
    length1in cm, length of a arc
    ratio.5arc length ratio
    gap2placing the point of construction
    size1radius of an arc (see bisector)

    Of course, you can add all the TikZ styles.

39.1.1 Example of \tkzShowLine and parallel

Compiled output

\begin{tikzpicture}
\tkzDefPoints{-1.5/-0.25/A,1/-0.75/B,-1.5/2/C}
\tkzDrawLine(A,B)
\tkzDefLine[parallel=through C](A,B) \tkzGetPoint{c}
\tkzShowLine[parallel=through C](A,B)
\tkzDrawLine(C,c) \tkzDrawPoints(A,B,C,c)
\end{tikzpicture}
39.1.2 Example of \tkzShowLine and perpendicular

Compiled output

\begin{tikzpicture}
\tkzDefPoints{0/0/A, 3/2/B, 2/2/C}
\tkzDefLine[perpendicular=through C,K=-.5](A,B)
\tkzGetPoint{c}
\tkzShowLine[perpendicular=through C,K=-.5,gap=3](A,B)
\tkzDefPointBy[projection=onto A--B](c)
\tkzGetPoint{h}
\tkzMarkRightAngle[fill=lightgray](A,h,C)
\tkzDrawLines[add=.5 and .5](A,B C,c)
\tkzDrawPoints(A,B,C,h,c)
\end{tikzpicture}
39.1.3 Example of \tkzShowLine and bisector

Compiled output

\begin{tikzpicture}[scale=1.25]
\tkzDefPoints{0/0/A, 4/2/B, 1/4/C}
\tkzDrawPolygon(A,B,C)
\tkzSetUpCompass[color=brown,line width=.1 pt]
\tkzDefLine[bisector](B,A,C) \tkzGetPoint{a}
\tkzDefLine[bisector](C,B,A) \tkzGetPoint{b}
\tkzInterLL(A,a)(B,b) \tkzGetPoint{I}
\tkzDefPointBy[projection = onto A--B](I)
\tkzGetPoint{H}
\tkzShowLine[bisector,size=2,gap=3,blue](B,A,C)
\tkzShowLine[bisector,size=2,gap=3,blue](C,B,A)
\tkzDrawCircle[color=blue,%
line width=.2pt](I,H)
\tkzDrawSegments[color=red!50](I,tkzPointResult)
\tkzDrawLines[add=0 and -0.3,color=red!50](A,a B,b)
\end{tikzpicture}
39.1.4 Example of \tkzShowLine and mediator

Compiled output

\begin{tikzpicture}
\tkzDefPoint(2,2){A}
\tkzDefPoint(5,4){B}
\tkzDrawPoints(A,B)
\tkzShowLine[mediator,color=orange,length=1](A,B)
\tkzGetPoints{i}{j}
\tkzDrawLines[add=-0.1 and -0.1](i,j)
\tkzDrawLines(A,B)
\tkzLabelPoints[below =3pt](A,B)
\end{tikzpicture}
39.2 Constructions of certain transformations \tkzShowTransformation
  • \tkzShowTransformation[⟨local options⟩](⟨pt1,pt2⟩) or (⟨pt1,pt2,pt3⟩)

  • These constructions concern orthogonal symmetries, central symmetries, orthogonal projections and translations. Several options adjust the constructions. The idea of this macro comes from Yves Combe.

    optionsdefaultdefinition
    reflection= over pt1–pt2reflectionconstructions of orthogonal symmetry
    symmetry=center ptreflectionconstructions of central symmetry
    projection=onto pt1–pt2reflectionconstructions of a projection
    translation=from pt1 to pt2reflectionconstructions of a translation
    K1circle within a triangle
    length1arc length
    ratio.5arc length ratio
    gap2placing the point of construction
    size1radius of an arc (see bisector)
39.2.1 Example of the use of \tkzShowTransformation

Compiled output

\begin{tikzpicture}[scale=.5]
\tkzDefPoint(0,0){O} \tkzDefPoint(2,-2){A}
\tkzDefPoint(70:4){B} \tkzDrawPoints(A,O,B)
\tkzLabelPoints(A,O,B)
\tkzDrawLine[add= 2 and 2](O,A)
\tkzDefPointBy[translation=from O to A](B)
\tkzGetPoint{C}
\tkzDrawPoint[color=orange](C) \tkzLabelPoints(C)
\tkzShowTransformation[translation=from O to A,%
length=2](B)
\tkzDrawSegments[->,color=orange](O,A B,C)
\tkzDefPointBy[reflection=over O--A](B) \tkzGetPoint{E}
\tkzDrawSegment[blue](B,E)
\tkzDrawPoint[color=blue](E)\tkzLabelPoints(E)
\tkzShowTransformation[reflection=over O--A,size=2](B)
\tkzDefPointBy[symmetry=center O](B) \tkzGetPoint{F}
\tkzDrawSegment[color=green](B,F)
\tkzDrawPoint[color=green](F)\tkzLabelPoints(F)
\tkzShowTransformation[symmetry=center O,%
length=2](B)
\tkzDefPointBy[projection=onto O--A](C)
\tkzGetPoint{H}
\tkzDrawSegments[color=magenta](C,H)
\tkzDrawPoint[color=magenta](H)\tkzLabelPoints(H)
\tkzShowTransformation[projection=onto O--A,%
color=red,size=3,gap=-2](C)
\end{tikzpicture}
39.2.2 Another example of the use of \tkzShowTransformation

You will find this figure again later, without the construction lines.

Compiled output

\begin{tikzpicture}[scale=.6]
\tkzDefPoints{0/0/A,8/0/B,3.5/10/I}
\tkzDefMidPoint(A,B) \tkzGetPoint{O}
\tkzDefPointBy[projection=onto A--B](I)
\tkzGetPoint{J}
\tkzInterLC(I,A)(O,A) \tkzGetPoints{M}{M'}
\tkzInterLC(I,B)(O,A) \tkzGetPoints{N}{N'}
\tkzDefMidPoint(A,B) \tkzGetPoint{M}
\tkzDrawSemiCircle(M,B)
\tkzDrawSegments(I,A I,B A,B B,M A,N)
\tkzMarkRightAngles(A,M,B A,N,B)
\tkzDrawSegment[style=dashed,color=blue](I,J)
\tkzShowTransformation[projection=onto A--B,
color=red,size=3,gap=-3](I)
\tkzDrawPoints[color=red](M,N)
\tkzDrawPoints[color=blue](O,A,B,I,M)
\tkzLabelPoints(O)
\tkzLabelPoints[above right](N,I)
\tkzLabelPoints[below left](M,A)
\end{tikzpicture}