A straight angle is 180 degrees or PI radians, so you can make a pattern of ellipses with the program:
100 FOR rot = 0 TO 2*PI STEP PI/6
110 CIRCLE 50,50,40,0.5,rot
120 END FOR rot
The order of the parameters for a circle or ellipse is:
centre _across, centre_up, height [eccentricity, angle]
The last two parameters are optional and this is indicated by putting them inside square brackets ([ ]).
Write a program which does the following:
1. Open a window 100x100 at (100,50)
2. Scale 100 in mode 8
3. Select black paper and clear window
4. Make green border 2 units wide
5. Draw a pattern of six coloured circles.
6. Close the window
100 REMark pattern
110 MODE 8
120 OPEN #7,scr_100x100a100x50
130 SCALE #7,100,0,0
140 PAPER #7,0 : CLS #7
150 BORDER #7,2,4
160 FOR colour = 1 TO 6
170 INK #7,colour
180 LET rot = 2*PI/colour
190 CIRCLE #7,50,50,30,0.5,rot
200 END FOR colour
210 CLOSE #7
You can get some interesting effects by altering the program. For example try the amendments:
160 FOR colour = 1 TO 100
180 LET rot = colour*PI/50
ARCS
If you want to draw an arc you need to decide:
starting point
end point
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