Image may be NSFW.
Clik here to view.LibreLogo can export SVG animations in the upcoming LibreOffice 4.3. The attached picture is the animated GIF preview of the SVG/SMIL Wikipedia animation about tangram drawing, see the SVG animation in your browser.
Saving animated SVG pictures needs to use only the SLEEP command within the PICTURE block. If the PICTURE block ends also with a SLEEP command, the result will be a looping SVG animation, as in this example.
TO place x y POSITION [200+x*40, 400-y*40] END TO line x y x2 y2 PENUP place x y PENDOWN place x2 y2 END TO grid x y x2 y2 REPEAT y2-y+1 [ line x y+REPCOUNT-1 x2 y+REPCOUNT-1 ] REPEAT x2-x+1 [ line x+REPCOUNT-1 y x+REPCOUNT-1 y2 ] END PICTURE “drawtangram.svg” [ PENSIZE 2 HIDETURTLE PENCAP “ROUND” PENCOLOR “SILVER” grid 0 0 4 4 SLEEP 1000 PENCOLOR “BLACK” line 0 4 4 0 SLEEP 1000 line 2 4 4 2 SLEEP 1000 line 1 3 2 4 SLEEP 1000 line 0 0 3 3 SLEEP 1000 line 3 3 3 1 SLEEP 1000 FILLCOLOR “RED” line 0 0 0 4 place 2 2 FILL FILLCOLOR “BLUE” line 0 0 4 0 place 2 2 FILL FILLCOLOR “GREEN” line 0 4 2 4 place 1 3 FILL FILLCOLOR “PURPLE” line 2 4 4 4 place 4 2 FILL FILLCOLOR “LIME” line 3 1 2 2 place 3 3 FILL FILLCOLOR “FUCHSIA” line 2 4 1 3 place 2 2 place 3 3 FILL FILLCOLOR “YELLOW” line 3 1 3 3 place 4 2 place 4 0 FILL SLEEP 2000 ]
Note: this code shows an example to use arbitrary Cartesian coordinate system with LibreLogo: the procedure place moves the turtle to the given coordinate, mapping it to the PostScript like coordinate system of LibreOffice. Procedure line calls place two times to draw a line. With combining line with place calls it’s possible to draw the filled tangram shapes using simple Cartesian coordinates.
The tangram is a popular dissection puzzle (see the LibreLogo turtle). Chinese mathematicians Fu Traing Wang and Chuan-Chih Hsiung proofed in 1942, that there are only 13 convex polygons can be formed by the tangram. Solving them is a good play (especially with a real tangram set):
Image may be NSFW.
Clik here to view.
[The solution (with an extended LibreLogo source code moving the origin of the Cartesian coordinate system to draw multiple shapes with simple Cartesian coordinates): convex tangram shapes (SVG).]