Help with directional input

AquaClouds · Posts: 8 Join date: 2008-07-17

I get an error whenever I try pressing any directional button. The error says "loop in gettable"
Here is my code:

Code:

cursor=Image.load("cursor.png")

while true do
pad = Controls.read()
screen:clear()

screen:blit(0,0,cursor)

if pad:left() then
cursor.x = cursor.x-10
end

if pad:right() then
cursor.x = cursor.x+10
end

if pad:up() then
cursor.y = cursor.y-10
end

if pad:down() then
cursor.y = cursor.y+10
end

screen.waitVblankStart()
screen.flip()
end

Thanks in advance for the help!

Tdude_gamer · Admin Posts: 6 Join date: 2008-07-16 Location: Hawaii

you don't have an array for the cursor and you need to blit the variable cursor.x and cursor.y, not as 0, cause the variable is stored as cursor.x, not 0. and use functions, it will clean up your code. use this exact code:

Code:

red = Color.new(255,0,0)

cursor = {x = 0, y = 0, img = Image.createEmpty(32,32)}
cursor.img:clear(red)

function controls()
if pad:up() then
cursor.y = cursor.y + 3
end

if pad:down() then
cursor.x = cursor.x - 3
end

if pad:left() then
cursor.x = cursor.x + 3
end

if pad:right() then
cursor.x = cursor.x - 3
end
end

while true do
screen:clear()
pad = Controls.read()

controls()

screen:blit(cursor.x,cursor.y,cursor.img)

screen.waitVblankStart()
screen.flip()
end

AquaClouds · Posts: 8 Join date: 2008-07-17

Okay, I think I understand better now, thanks for the help.
Now I've just gotta work on only moving it upon the "release" of the directional keys.

EDIT: After reviewing the tutorials, I understand how it works now. I tried to increase/decrease a variable that I had not defined yet. Thanks again for the help!

Your code had only one line that contained an error and if anyone else would like to use the code I'm going to post the correct changes:
From this:

Code:

if pad:down() then
cursor.x = cursor.x - 3
end

To this:

Code:

if pad:down() then
cursor.y = cursor.y + 3
end

Tdude_gamer · Admin Posts: 6 Join date: 2008-07-16 Location: Hawaii

sorry, for the error, i guess i was kind of careless when i typed that. i will edit the code on my post. and it should be:

Code:

if pad:up() then
cursor.y = cursor.y + 3
end

not:

Code:

if pad:down() then
cursor.y = cursor.y + 3
end