Page 89 - TechPluse_C4_Flipbook
P. 89
set pen color to 50 block will set the pen colour, saturation, brightness and
transparency to the given value.
Clickipedia
A loop is a process which instructs a computer to repeat a set of commands,
a specified number of times.
DRAWING POLYGONS
Polygons are 2D shapes with three or more straight lines and angles. Examples of
polygons are triangle, square, rectangle, quadrilateral, pentagon, octagon, etc.
Triangle Square Pentagon Hexagon Heptagon Octagon Nonagon Decagon
(3 sides) (4 sides) (5 sides) (6 sides) (7 sides) (8 sides) (9 sides) (10 sides)
To draw polygons in Scratch, you must remember a few thumb rules. These are as
follows:
You must know the number of sides of the shape. This is the value to be given
in Repeat block. For example, you give Repeat 3 to draw a triangle and 4 to draw
a square.
Each time a Repeat block is used, you draw a line and turn at a corner.
You must know the degree of the angle at the corner. It is very easy to calculate
this. Just divide 360 by the number of sides of the shape. For example, to draw a
triangle, the turn will be 360/3 (sides of the triangle) = 120.
Look at these polygons that can be made using Repeat block.
Polygon Command
Triangle Repeat 3 Move 100 Steps Turn 120 degrees
Square Repeat 4 Move 100 Steps Turn 90 degrees
Pentagon Repeat 5 Move 100 Steps Turn 72 degrees
Hexagon Repeat 6 Move 100 Steps Turn 60 degrees
Heptagon Repeat 7 Move 100 Steps Turn 51 degrees
Octagon Repeat 8 Move 100 Steps Turn 45 degrees
Programming in Scratch 87

