How to draw a line controlled by user..

[hq78]

My Code for cursor controlling:


var x, y : int := 100
var col : int := 16
var switch := 0
var chars : array char of boolean

loop
if switch = 0 then
col := col + 1
elsif switch = 1 then
col := col - 1
end if
if col = 30 then
switch := 1
elsif col = 16 then
switch := 0
end if
drawfilloval (x, y, 1, 1, col)
delay (5)
Input.KeyDown (chars)
if chars (KEY_UP_ARROW) and y < maxy then
y := y + 1
end if
if chars (KEY_DOWN_ARROW) and y > 0 then
y := y - 1
end if
if chars (KEY_LEFT_ARROW) and x > 0 then
x := x - 1
end if
if chars (KEY_RIGHT_ARROW) and x < maxx then
x := x + 1
end if
end loop

I need to change the drawfilloval into drawline so the user can control a line instead of an oval but when i do it draws it horribly wrong. I want to make a snake game, and i need the tail of the line to follow the user's cursor movements. Can someone tell me how to do it? or give me hints to how to do it? Thanks in advanced

[McKenzie]

Hey cool "etch-a-sketch",

The difference between a line and an oval is that you need two points with a line and only one with an oval. If you wanted to use a line you would need to keep track of the old x and y positions each time around the loop.

Unfortunately that won't get you any further ahead in making your snake game, just a different version of your "etch-a-sketch". What you need to do is see your snake as a number of segments. You can draw the segments as ovals, boxes or bitmaps.... The important part is how you store the locations of all of the segments. You will need to use an array for that.

[hq78]

thanks for an idea!