Commands, color constants are case insensitive:
PRINT “Hello, World!”
print “Hello, World, again!”
Variable names are case sensitive:
a = 5
A = 7
PRINT a
PRINT A
Lines of a LibreLogo program are paragraphs in the Writer document. A program line can contain multiple commands:
PRINT “Hello, World!” PRINT “LibreLogo”
Lines or line parts are comments from a semicolon to the end of the line (paragraph):
; some comments
PRINT 5 * 5 ; some comments
It’s possible to break a program line for more paragraphs using the character tilde at the end of the line:
Ejemplo:
PRINT ‘Un ejemplo de un largo mensa’~
‘je que no entra en una sola lí’~
‘nea.’
Salida: Un ejemplo de un largo mensaje que no entra en una sola línea,
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Turtle moving
FORWARD 10 ; move forward 10pt (1pt = 1/72 inch)
FORWARD 10pt ; see above
FORWARD 0.5in ; move forward 0.5 inch (1 inch = 2.54 cm)
FORWARD 1" ; see above
FD 1mm
FD 1cm
BACK 10 ; move back 10pt
LEFT 90 ; turn counterclockwise 90 degrees
LEFT 90° ; see above
LT 3h ; see above (clock position)
LT any ; turn to a random position
RIGHT 90 ; turn clockwise 90 degrees
PENUP ; turtle will move without drawing
PENDOWN ; turtle will move with drawing
POSITION [0, 0] ; turn and move to the top-left corner
POSITION PAGESIZE ; turn and move to the bottom-right corner
POSITION [PAGESIZE[0], 0] ; turn and move to the top-right corner
POSITION ANY ; turn and move to a random position
HEADING 0 ; turn north
HEADING 12h ; see above
HEADING [0, 0] ; turn to the top-left corner
HEADING ANY ; turn to a random direction
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HIDETURTLE ; hide turtle (until the showturtle command)
SHOWTURTLE ; show turtle
HOME ; reset initial turtle position
CLEARSCREEN ; remove drawing objects of the document
FILL ; close and fill the actual line shape or points
CLOSE ; close the actual line shape or join the actual points
Example: filling a regular triangle:
FORWARD 50 LEFT 120 FORWARD 50 FILL
Example: drawing a regular triangle:
FORWARD 50 LEFT 120 FORWARD 50 CLOSE
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PENSIZE 100 ; line width is 100 points
PENSIZE ANY ; equivalent of PENSIZE RANDOM 10
PENCOLOR “red” ; set red pen color (by color name, see color constants)
PENCOLOR [255, 255, 0] ; set yellow color (RGB list)
PENCOLOR 0xffff00 ; set yellow color (hexa code)
PENCOLOR 0 ; set black color (0x000000)
PENCOLOR ANY ; random color
PENCOLOR [5] ; set red color (by color identifier, see color constants)
PENCOLOR “invisible” ; invisible pen color for shapes without visible outline
PENCOLOR “~red” ; set random red color
PENTRANSPARENCY 80 ; set the transparency of the actual pen color to 80%
PENCAP “none” ; without extra line end (default)
PENCAP “round” ; rounded line end
PENCAP “square” ; square line end
PENJOINT “rounded” ; rounded line joint (default)
PENJOINT “miter” ; sharp line joint
PENJOINT “bevel” ; bevel line joint
PENJOINT “none” ; without line joint
PENSTYLE “solid” ; solid line (default)
PENSTYLE “dotted” ; dotted line
PENSTYLE “dashed” ; dashed line
; custom dot–dash pattern specified by a list with the following arguments:
; – number of the neighbouring dots
; – length of a dot
; – number of the neighbouring dashes
; – length of a dash
; – distance of the dots/dashes
; – type (optional):
; 0 = dots are rectangles (default)
; 2 = dots are squares (lengths and distances are relative to the pensize)
PENSTYLE [3, 1mm, 2, 4mm, 2mm, 2] ; ...––...––...––
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FILLCOLOR “blue” ; fill with blue color, see also PENCOLOR
FILLCOLOR “invisible” CIRCLE 10 ; unfilled circle
FILLCOLOR [“blue”, “red”] ; gradient between red and blue
FILLCOLOR [[255, 255, 255], [255, 128, 0]] ; between white and orange
FILLCOLOR [“blue”, “red”, 1, 0, 0] ; set axial gradient (with the required rotation and border settings), possible values: 0-5 = linear, axial, radial, elliptical, square and rectangle gradients
FILLCOLOR [“red”, “blue”, 0, 90, 20] ; linear with 20% border, rotated with 90 degrees from the actual heading of the turtle
FILLCOLOR [“red”, “blue”, 0, 90, 20, 0, 0, 200, 50] ; from 200% to 50% intensity
FILLCOLOR [ANY, ANY, 2, 0, 0, 50, 50] ; radial gradient with random colors and 50-50% horizontal and vertical positions of the center
FILLTRANSPARENCY 80 ; set the transparency of the actual fill color to 80%
FILLTRANSPARENCY [80] ; set linear transparency gradient from 80% to 0%
FILLTRANSPARENCY [80, 20] ; set linear transparency gradient from 80% to 20%
FILLTRANSPARENCY [80, 20, 1, 90] ; set axial transparency gradient rotated with 90 degrees from the actual heading of the turtle
FILLTRANSPARENCY [80, 20, 2, 0, 20, 50, 50] ; set radial transparency gradient from outer 80% to inner 20% transparency with 20% border and with 50-50% horizontal and vertical positions of the center
FILLSTYLE 0 ; fill without hatches (default)
FILLSTYLE 1 ; black single hatches (horizontal)
FILLSTYLE 2 ; black single hatches (45 degrees)
FILLSTYLE 3 ; black single hatches (-45 degrees)
FILLSTYLE 4 ; black single hatches (vertical)
FILLSTYLE 5 ; red crossed hatches (45 degrees)
FILLSTYLE 6 ; red crossed hatches (0 degrees)
FILLSTYLE 7 ; blue crossed hatches (45 degrees)
FILLSTYLE 8 ; blue crossed hatches (0 degrees)
FILLSTYLE 9 ; blue triple crossed
FILLSTYLE 10 ; black wide single hatches (45 degrees)
; custom hatches specified by a list with the following arguments:
; – style (1 = single, 2 = double, 3 = triple hatching)
; – color
; – distance
; – degree
FILLSTYLE [2, “green”, 3pt, 15°] ; green crossed hatches (15 degrees)
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CIRCLE 100 ; draw a circle shape (diameter = 100pt)
ELLIPSE [50, 100] ; draw an ellipse with 50 and 100 diameters
ELLIPSE [50, 100, 2h, 12h] ; draw an elliptical sector (from 2h clock position to 12h)
ELLIPSE [50, 100, 2h, 12h, 2] ; draw an elliptical segment
ELLIPSE [50, 100, 2h, 12h, 3] ; draw an elliptical arc
SQUARE 100 ; draw a square shape (size = 100pt)
RECTANGLE [50, 100] ; draw a rectangle shape (50×100pt)
RECTANGLE [50, 100, 10] ; draw a rectangle with rounded corners
POINT ; draw a point with size and color of the pen
CLOSE can join the last points, FILL can fill the shape defined by points. For example, it’s easy to draw a “flat” star starting from its center:
PENUP
REPEAT 5 [
FORWARD 80
POINT
BACK 80
RIGHT 36
FORWARD 50
POINT
BACK 50
RIGHT 120
] FILL
LABEL “text” ; print text in the turtle position
LABEL 'text' ; see above
LABEL "text ; see above (only for single words)
CIRCLE 10 TEXT “text” ; set text of the actual drawing object
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FONTCOLOR “green” ; set font color
FONTFAMILY “Linux Libertine G” ; set font (family)
FONTFAMILY “Linux Libertine G:smcp=1” ; set also font feature (small caps)
FONTFAMILY “Linux Libertine G:smcp=1&onum=1” ; small caps + old figures
FONTSIZE 12 ; set 12pt
FONTWEIGHT “bold” ; set bold font
FONTWEIGHT “normal” ; set normal weight
FONTSTYLE “italic” ; set italic variant
FONTSTYLE “normal” ; set normal variant
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PICTURE is for
· shape grouping;
· starting new line shapes;
· saving SVG images and SVG/SMIL animations;
· keeping the consistency of positions and line shapes at the left border.
; PICTURE [ LibreLogo_commands ]
PICTURE [ FORWARD 100 CIRCLE 100 ] ; tree-like grouped shape
See also “Group” in LibreOffice Writer Help.
TO tree location
PENUP POSITION location HEADING 0 PENDOWN
PICTURE [ FORWARD 100 CIRCLE 100 ] ; tree-like grouped shape
END
PICTURE [ tree [230, 400] tree [300, 400] ] ; grouped shapes in a grouped shape
PICTURE ; start a new line shape
FORWARD 10 PICTURE FORWARD 10 ; two line shapes
PICTURE “example.svg” [ CIRCLE 5 ] ; save the picture as an SVG image file in the user folder
PICTURE “Desktop/example.svg” [ FORWARD 100 CIRCLE 5 ] ; as above, with a relative path
PICTURE “/home/user/example.svg” [ CIRCLE 5 ] ; absolute path for Unix/Linux
PICTURE “C:\example.svg” [ CIRCLE 5 ] ; absolute path for Windows
Use PICTURE to keep the consistency of positions and line shapes at the left border of Writer:
PICTURE [ CIRCLE 20 POSITION [-100, 100] CIRCLE 20 ]
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; REPEAT number [ commands ]
REPEAT 10 [ FORWARD 10 LEFT 45 CIRCLE 10 ] ; repeat 10 times
; number is optional
REPEAT [ POSITION ANY ] ; endless loop
Loop variable (also in the FOR and WHILE loops).
REPEAT 100 [ FORWARD REPCOUNT LEFT 90 ]
Loop for the list elements:
FOR i IN [1, 5, 7, 9, 11] [
FORWARD i
LEFT 90
]
Loop for the characters of a character sequence:
FOR i IN “text” [
LABEL i
FORWARD 10
]
WHILE TRUE [ POSITION ANY ] ; endless loop
WHILE REPCOUNT <= 10 [ FORWARD 50 LEFT 36 ] ; as REPEAT 10 [ ... ]
Stop the loop.
REPEAT [ ; endless loop
POSITION ANY
IF REPCOUNT = 100 [ BREAK ] ; equivalent of the REPEAT 100 [ ... ]
]
Jump into the next iteration of the loop.
REPEAT 100 [
POSITION ANY
IF REPCOUNT % 2 = 0 [ CONTINUE ]
CIRCLE 10 ; draw circles on every 2nd positions
]
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Condicionales
; IF condition [ true block ]
; IF condition [ true block ] [ false block ]
IF a < 10 [ PRINT “Small” ]
IF a < 10 [ PRINT “Small” ] [ PRINT “Big” ]
Logical operators.
IF a < 10 AND NOT a = 5 [ PRINT “0, 1, 2, 3, 4, 6, 7, 8 or 9” ]
IF a < 10 AND a != 5 [ PRINT “0, 1, 2, 3, 4, 6, 7, 8 or 9” ] ; as above
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New word (or procedure).
TO triangle
REPEAT 2 [ FORWARD 100 RIGHT 120 ] FILL
END
REPEAT 10 [ triangle PENUP POSITION ANY PENDOWN ]
Return value of the function.
TO randomletter
OUTPUT RANDOM “qwertzuiopasdfghjklyxcvbnm”
END
PRINT randomletter + randomletter + randomletter ; print 3-letter random character sequence
Return from the procedure.
TO example number
IF number < 0 [ STOP ]
PRINT SQRT number ; print square root
]
example 100
example -1 ; without output and error
example 25
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Default random value of colors, etc.
PENCOLOR ANY ; random pen color
Logical value.
WHILE TRUE [ POSITION ANY ] ; endless loop
PRINT TRUE ; print true
Logical value.
WHILE NOT FALSE [ POSITION ANY ] ; endless loop
PRINT FALSE ; print false
PRINT PAGESIZE ; print list of the page sizes in points, eg. [595.30, 841.89]
PRINT PI ; print 3.14159265359
________
PRINT “text” ; print “text” in a dialog box
PRINT 5 + 10 ; print 15
PRINT INPUT “Input value?” ; ask and print a string by a query dialog box
PRINT FLOAT (INPUT “First number?”) + FLOAT (INPUT “Second number?”) ; simple calculator
SLEEP 1000 ; wait for 1000 ms (1 sec)
Set global variables used in procedures.
GLOBAL about
about = “LibreLogo”
TO example
PRINT about
GLOBAL about ; when we want to add a new value
about = “new value for the global variable”
END
example
PRINT about
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PRINT RANDOM 100 ;da un número decimal aleatorio (0 <= x < 100)
PRINT RANDOM “Mi texto” ;da un caractér aleatorio de un texto “Mi texto”
PRINT RANDOM [1, 2] ;da un elemento aleatorio de una lista (por ejemplo 1 or 2)
PRINT SQRT 100 ;muestra 10, raíz cuadrada de 100
PRINT SIN 90 * PI/180 ;muestra 1.0 (seno de 90° en radianes)
PRINT COS 0 * PI/180 ;muestra 1.0 (coseno de 0°, en radianes)
PRINT LOG10 100 ;muestra 2.0 ( logaritmo de 100)
PRINT ROUND 3.8 ;muestra el numero redondeado: 4
PRINT ROUND RANDOM 100 ;muestra número entero (redondeado entre 0 100)
; remove the repeating elements of a list using set and list conversion
PRINT LIST (SET [1, 3, 5, 5, 2, 1]) ; print [1, 3, 5, 2]
It returns with a sorted list.
PRINT SORTED [5, 1, 3, 4] ; print [1, 3, 4, 5]
Substitute character sequences using regex (regular expression) patterns.
PRINT SUB (“t”, “T”, “text”) ; print “Text”, replacing “t” with “T”
PRINT SUB (“(.)”, “\\1\\1”, “text”) ; print “tteexxtt”, doubling every characters
Search character sequences patterns using regex patterns.
IF SEARCH (“\w”, "word") [ PRINT “Letter in the word.” ]
Find all character sequences in the input string matching the given regex pattern.
PRINT FINDALL(“\w+”, “Dogs, cats.”) ; print [“Dogs”, “cats”], the list of the words.
PRINT MIN [1, 2, 3] ; print 1, the lowest element of the list
PRINT MAX [1, 2, 3] ; print 3, the greatest element of the list