LUA - LÖVE 2D - Sprite dying when hitting a box - lua

Question

--Okay, basically I've set up pretty much everything i want in the game. All i have to do now is create the enemies. I've set up the spawning and movement but when the player hits the enemies, nothing happens. When the red ball hits the blocks i'd like the client to close. (i will obviously change this at a later date but its only temporary) I'd be very grateful if you could program the code that would interpret this within the game. I'm new to this programming language and I'm only 15 still learning how to code. I am more than happy to give you credit in the game.
Thank you - Olee
function love.load()
love.graphics.setBackgroundColor( 110, 110, 110 ) --Sets background colour
love.graphics.rectangle("fill",400,300,0,230,230) --Draws game background
print("Olee's Game") -- prints into the console
x=140 --x position of sprite
y=320 --y position of the sprite
swidth=20 --sprite width
sheight=20 --sprite height
evil=900 --red rectangular blocks x position
evilheight=64 --red rectangular block height
evilwidth=256 --red rectangular block width
points=0 --point system created variable
random1y=math.random(120,480) --creates y position of the first enemy block
random2y=math.random(120,480) --creates y position of the block
random3y=math.random(120,480) --creates y position of the block
random4y=math.random(120,480) --creates y position of the block
random5y=math.random(120,480) --creates y position of the block
random6y=math.random(120,480) --creates y position of the block
end
function love.update(dt)
--BOUNDRIES--(makes the sprite not go off the page)
if y<120 then
y=y+20
end
if y>520 then
y=y-20
end
if x<20 then
x=x+20
end
if x>780 then
x=x-20
end
--AI (sends the blocks back to the start)
evil=evil-400*dt
if evil<=(-400) then
evil=1100
random1y=math.random(120,480)
random2y=math.random(120,480)
random3y=math.random(120,480)
random4y=math.random(120,480)
random5y=math.random(120,480)
random6y=math.random(120,480)
end
--Points
points = love.timer.getTime()
points=math.floor(points)
end
function love.focus(bool)
end
function love.keypressed( key, unicode )
print("You just pressed "..key)
print("x="..x.."\ny="..y.."\n#########")
if key=="escape"then
print("Bye!")
os.exit(0)
end
if key == "down" then
y=y+20
end
if key == "left" then --A KEY (LEFT)
x=x-20
end
if key == "right" then --D KEY (RIGHT)
x=x+20
end
if key == "up" then --W KEY (UP)
y=y-20
end
end
function love.draw()
--Floor
love.graphics.setColor(127, 127, 127)
love.graphics.rectangle("fill",0,540,5000,100)
--Ceiling
love.graphics.setColor(127, 127, 127)
love.graphics.rectangle("fill", 0, 0, 5000, 100)
--Welcome Message
love.graphics.setColor(191, 0, 52)
love.graphics.print("Bonjourno and Welcome to Olee's Game",32,32,0,1,1)
--Welcome Message HUD Box
love.graphics.setColor(191, 0, 52)
love.graphics.rectangle("line",16,18,284,48)
--Circle (sprite)
love.graphics.setColor(191, 0, 52)
love.graphics.circle("fill",x,y,swidth,sheight)
--SCOREBOARD
love.graphics.setColor(191, 0, 52)
love.graphics.print("Score: "..points.."",620, 35)
--Evil 1
love.graphics.setColor(191, 0, 52)
love.graphics.rectangle("fill",evil,random1y,evilwidth,evilheight)
--Evil 2
love.graphics.setColor(191, 0, 52)
love.graphics.rectangle("fill",evil,random2y,evilwidth,evilheight)
--Evil 3
love.graphics.setColor(191, 0, 52)
love.graphics.rectangle("fill",evil,random3y,evilwidth,evilheight)
--Evil 4
love.graphics.setColor(191, 0, 52)
love.graphics.rectangle("fill",evil,random4y,evilwidth,evilheight)
--Evil 5
love.graphics.setColor(191, 0, 52)
love.graphics.rectangle("fill",evil,random5y,evilwidth,evilheight)
--Evil 6
love.graphics.setColor(191, 0, 52)
love.graphics.rectangle("fill",evil,random6y,evilwidth,evilheight)
--FPS
love.graphics.print("FPS: "..tostring(love.timer.getFPS( )), 735, 5)
end
function love.quit()
end
Just to let you guys know, I HAVE set up a conf.lua file. My game works perfectly but i would like to add this! :)
and i have a play.bat
conf.lua:
function love.conf(t)
t.modules.joystick = true -- Enable the joystick module (boolean)
t.modules.audio = true -- Enable the audio module (boolean)
t.modules.keyboard = true -- Enable the keyboard module (boolean)
t.modules.event = true -- Enable the event module (boolean)
t.modules.image = true -- Enable the image module (boolean)
t.modules.graphics = true -- Enable the graphics module (boolean)
t.modules.timer = true -- Enable the timer module (boolean)
t.modules.mouse = true -- Enable the mouse module (boolean)
t.modules.sound = true -- Enable the sound module (boolean)
t.modules.timer = true -- Enable the timer module (boolean)
t.modules.thread = true
t.modules.math = true -- Enable the math module (boolean)
t.modules.physics = true -- Enable the physics module (boolean)
t.console = true -- Attach a console (boolean, Windows only)
t.title = "Olee's Game" -- The title of the window the game is in (string)
t.author = "Olee" -- The author of the game (string)
t.screen.fullscreen = false -- Enable fullscreen (boolean)
t.screen.vsync = false -- Enable vertical sync (boolean)
t.screen.fsaa = 0 -- The number of FSAA-buffers (number)
t.screen.height = 600 -- The window height (number)
t.screen.width = 800 -- The window width (number)
end
play.bat:
#ECHO OFF
start "" "C:\Program Files (x86)\LOVE\love.exe" .

Answer 1

Well, you have two approaches here:
You can do advanced collision
You can do simple collision.
The second is simpler, but the first is much better for this sort of game.
First approach:
First, you need to know this code:
function circleAndRectangleOverlap( circleX, circleY, circleRadius, rectangleX, rectangleY, rectangleWidth, rectangleHeight )
local distanceX = math.abs( circleX - rectangleX - rectangleWidth / 2 )
local distanceY = math.abs( circleY - rectangleY - rectangleHeight / 2 )
if distanceX > ( rectangleWidth / 2 + circleRadius ) or distanceY > ( rectangleHeight /2 + circleRadius ) then
return false
elseif distanceX <= ( rectangleWidth / 2 ) or distanceY <= ( rectangleHeight / 2 ) then
return true
end
return ( math.pow( distanceX - rectangleWidth / 2, 2 ) + math.pow( distanceY - rectangleHeight / 2, 2 ) ) <= math.pow( circleRadius, 2 )
end
Then you can add this to the rest of this code.
function love.load()
love.graphics.setBackgroundColor( 110, 110, 110 ) --Sets background colour
love.graphics.rectangle("fill",400,300,0,230,230) --Draws game background
print("Olee's Game") -- prints into the console
x=140 --x position of sprite
y=320 --y position of the sprite
sradius=20 --sprite radius
evil=900 --red rectangular blocks x position
evilheight=64 --red rectangular block height
evilwidth=256 --red rectangular block width
points=0 --point system created variable
random1y=math.random(120,480) --creates y position of the first enemy block
random2y=math.random(120,480) --creates y position of the block
random3y=math.random(120,480) --creates y position of the block
random4y=math.random(120,480) --creates y position of the block
random5y=math.random(120,480) --creates y position of the block
random6y=math.random(120,480) --creates y position of the block
end
function love.update(dt)
--BOUNDRIES--(makes the sprite not go off the page)
if y<120 then
y=y+20
end
if y>520 then
y=y-20
end
if x<20 then
x=x+20
end
if x>780 then
x=x-20
end
--AI (sends the blocks back to the start)
evil=evil-400*dt
if evil<=(-400) then
evil=1100
random1y=math.random(120,480)
random2y=math.random(120,480)
random3y=math.random(120,480)
random4y=math.random(120,480)
random5y=math.random(120,480)
random6y=math.random(120,480)
end
--Points
points = love.timer.getTime()
points=math.floor(points)
-- Check collisions
if circleAndRectangleOverlap( x, y, sradius, evil, random1y, evilwidth, evilheight )
or circleAndRectangleOverlap( x, y, sradius, evil, random2y, evilwidth, evilheight )
or circleAndRectangleOverlap( x, y, sradius, evil, random3y, evilwidth, evilheight )
or circleAndRectangleOverlap( x, y, sradius, evil, random4y, evilwidth, evilheight )
or circleAndRectangleOverlap( x, y, sradius, evil, random5y, evilwidth, evilheight )
or circleAndRectangleOverlap( x, y, sradius, evil, random6y, evilwidth, evilheight ) then
love.event.quit()
end
end
function love.focus(bool)
end
function love.keypressed( key, unicode )
print("You just pressed "..key)
print("x="..x.."\ny="..y.."\n#########")
if key=="escape"then
print("Bye!")
love.event.quit()
end
if key == "down" then
y=y+20
end
if key == "left" then --A KEY (LEFT)
x=x-20
end
if key == "right" then --D KEY (RIGHT)
x=x+20
end
if key == "up" then --W KEY (UP)
y=y-20
end
end
function love.draw()
--Floor
love.graphics.setColor(127, 127, 127)
love.graphics.rectangle("fill",0,540,5000,100)
--Ceiling
love.graphics.setColor(127, 127, 127)
love.graphics.rectangle("fill", 0, 0, 5000, 100)
--Welcome Message
love.graphics.setColor(191, 0, 52)
love.graphics.print("Bonjourno and Welcome to Olee's Game",32,32,0,1,1)
--Welcome Message HUD Box
love.graphics.setColor(191, 0, 52)
love.graphics.rectangle("line",16,18,284,48)
--Circle (sprite)
love.graphics.setColor(191, 0, 52)
love.graphics.circle("fill",x,y,sradius)
--SCOREBOARD
love.graphics.setColor(191, 0, 52)
love.graphics.print("Score: "..points.."",620, 35)
--Evil 1
love.graphics.setColor(191, 0, 52)
love.graphics.rectangle("fill",evil,random1y,evilwidth,evilheight)
--Evil 2
love.graphics.setColor(191, 0, 52)
love.graphics.rectangle("fill",evil,random2y,evilwidth,evilheight)
--Evil 3
love.graphics.setColor(191, 0, 52)
love.graphics.rectangle("fill",evil,random3y,evilwidth,evilheight)
--Evil 4
love.graphics.setColor(191, 0, 52)
love.graphics.rectangle("fill",evil,random4y,evilwidth,evilheight)
--Evil 5
love.graphics.setColor(191, 0, 52)
love.graphics.rectangle("fill",evil,random5y,evilwidth,evilheight)
--Evil 6
love.graphics.setColor(191, 0, 52)
love.graphics.rectangle("fill",evil,random6y,evilwidth,evilheight)
--FPS
love.graphics.print("FPS: "..tostring(love.timer.getFPS( )), 735, 5)
end
function love.quit()
end
Second Approach
This uses the AABB aproach, which will be more useful if you use actual sprites in the future.
Just plug this in for the circleAndRectangleOverlap with this (and width and height arguments instead of radius):
function checkAABB( spriteX, spriteY, spriteWidth, spriteHeight, rectangleX, rectangleY, rectangleWidth, rectangleHeight )
if ( ( spriteX >= rectangleX + rectangleWidth)
or ( spriteX + spriteWidth <= rectangleX )
or ( spriteY >= rectangleY + rectangleHeight )
or ( spriteY + spriteHeight <= rectangleY ) ) then
return false
else return true
end
end
end