For loop problem

[leyohla]

Sorry to post again on a similar question but I've been racking my brain and internet all day but still totally unsure of what I am doing wrong here...

Code: Select all

balls = {} 
function addBalls(x, y)

    local ball = Ball:init(x, y)
    table.insert(balls, ball)

    for i in ipairs(balls) do
        love.graphics.draw(ball.x, ball.y)
    end

end

So I want to spawn multiple balls when calling this 'addBalls' function. For each ball in the table 'balls', I want to draw a ball onto the screen whenever this function is called, but for some reason this is not happening.

Here's the file:

Ball.lua

(2.92 KiB) Downloaded 173 times

Here's how I call this function:

Code: Select all

if self.powerup:collides(self.paddle) then
        powerup = false
        addBalls(x,y)
    end

Just a disclaimer to say I am new to Lua and a noob programmer !!

[sphyrth]

Code: Select all

for i in ipairs(balls) do
    love.graphics.draw(ball.x, ball.y)
end

Don't put that in addBalls. Put that under love.draw.

And write it like this instead:

Code: Select all

for _, b in pairs(balls) do
    love.graphics.draw(b.x, b.y)
end

Take note that i used pairs instead of ipairs, although that might work, too.

[leyohla]

Thanks so much @sphyrth

[CanYouReply]

Hi,
I am new around here. Recently while experimenting with 'ipairs' I am finding an issue which I can't solve. May I request a slight, bit help from the experts....
This code is written in 'main.lua' file & I am finding a problem - which I can't overcome... I created a table for a bigger box. In this bigger box there are multiple smaller boxes. I am trying to access the presence of mouse clicks inside & outside of these multiple smaller boxes. Now when I am clicking inside these multiple boxes (not the big box) I can get response that mouse is being clicked inside these smaller boxes. However, when I am clicking outside these multiple boxes, I can't get any response on mouse click. I need both the responses. Can you please help ?? I am giving below the complete codes for your help. Thanks in advance. :

Code: Select all

function love.load(arg)
  -- get window width
  windowWidth = love.graphics.getWidth()

  -- get window height
  windowHeight = love.graphics.getHeight()

  -- create table for the big box:
  bigBox = {}
  bigBox.width = 480
  bigBox.height = 150
  bigBox.x = windowWidth/2 - bigBox.width/2
  bigBox.y = windowHeight/2 -bigBox.height/2

  -- create small small boxes
  smallBoxes = {}
    for i=1, 3 do
      local box = {}
      box.width = 103
      box.height = 103
        if i == 1 or i == 2  or i == 3 then  -- first row
          box.x = i * (box.width + 10) + (windowWidth/2 - bigBox.width/2 + 10)
          box.y = windowHeight/2 - bigBox.height/2 + 10
        end
      table.insert(smallBoxes, box)
  end

  -- communication of game with players
  textDisplay = ""

  -- initialising and getting mouse positions (without clicks)
  mouse_x = love.mouse.getX()
  mouse_y = love.mouse.getY()

  --load game state as 'start'
  gameState = 'start'
end


function love.update(dt)
  -- getting mouse x, y positions (irrespective of clicks)
  mouse_x = love.mouse.getX()
  mouse_y = love.mouse.getY()

  --Access the 'box' parameters (like: box.x, box.y, box.width, box.height) under 'smallBoxes' through 'ipairs' procedure
      for ii, vv in ipairs(smallBoxes) do
          -- now check click of mouse on box areas  and check check if mouse then is inside the small boxes area or not
          if love.mouse.isDown(1) and CheckCollision(mouse_x, mouse_y, 0, 0, vv.x, vv.y, vv.width, vv.height) then
              gameState = 'play' -- At this point we can change game state from 'start' to 'play'
              textDisplay = 'You have clicked inside one of the small boxes'
              -- now do other process --
          end
      end
end



function love.draw()
  -- draw the big box
  love.graphics.setColor(200, 200, 60, 255)
  love.graphics.rectangle('fill', bigBox.x, bigBox.y, bigBox.width, bigBox.height)
  -- draw the small boxes
  love.graphics.setColor(130, 95, 250, 255)
  for i,b in ipairs(smallBoxes) do
    love.graphics.rectangle('fill', b.x, b.y, b.width, b.height)
  end
  -- game communucation with players
  love.graphics.setColor(0, 255, 255, 255)
  love.graphics.print(": "..textDisplay, 20, 540)
end



function CheckCollision(ax1,ay1,aw,ah, bx1,by1,bw,bh)
  local ax2,ay2,bx2,by2 = ax1 + aw, ay1 + ah, bx1 + bw, by1 + bh
  return ax1 < bx2 and ax2 > bx1 and ay1 < by2 and ay2 > by1
end

[4vZEROv]

I don't understand what you are trying to do, do you want to check if you click inside the big rectangle and not the small ones ?

[CanYouReply]

I have already got mouse click event inside the small rectangles, at the same time I want to check if I can get mouse click event outside the small rectangles. (please ignore the big rectangle).
That means when I click inside any small rectangles I will get a text display 'mouse clicked inside small rectangles' and when I click outside the small rectangles I will get text display 'mouse clicked outside small rectangles'

[Andlac028]

Something like this? If clicked in any small rectangle, set clickedInRectangle to true, else its false and at the end, check whetever clickedInRectangle is true or false.

Code: Select all

function love.update(dt)
  -- getting mouse x, y positions (irrespective of clicks)
  mouse_x = love.mouse.getX()
  mouse_y = love.mouse.getY()
  
  --ADDED
  local clickedInRectangle = false -- whatever clicked in any small rectangle

  --Access the 'box' parameters (like: box.x, box.y, box.width, box.height) under 'smallBoxes' through 'ipairs' procedure
      for ii, vv in ipairs(smallBoxes) do
          -- now check click of mouse on box areas  and check check if mouse then is inside the small boxes area or not
          if love.mouse.isDown(1) and CheckCollision(mouse_x, mouse_y, 0, 0, vv.x, vv.y, vv.width, vv.height) then
              gameState = 'play' -- At this point we can change game state from 'start' to 'play'
              textDisplay = 'You have clicked inside one of the small boxes'
              
              --ADDED
              clickedInRectangle = true -- make it true, because clicked in small rectangle
              
              -- now do other process --
          end
      end
      
      --ADDED
      if not clickedInRectangle then --if not clicked in any small rectangle
      	textDisplay = 'You have clicked outside of the small boxes'
      end 
end

[CanYouReply]

Thanks. But as soon as the program starts, without any click, it shows ' you have clicked outside the rectangle'. Moreover I have to keep the mouse button pressed inside the small boxes to get a response that I have clicked inside the mouse button. Can you please rephrase the codes in such a way that once clicked inside the small rectangles, the text message will show 'mouse clicked inside' & it will remain in that way till user is clicking outside the boxes - when it will display 'clicked outside' ?

[4vZEROv]

Code: Select all

function love.load(arg)
	windowWidth = love.graphics.getWidth()
	windowHeight = love.graphics.getHeight()

	-- create table for the big box:
	bigBox = {}
	bigBox.width = 480
	bigBox.height = 150
	bigBox.x = windowWidth/2 - bigBox.width/2
	bigBox.y = windowHeight/2 -bigBox.height/2

	-- create small small boxes
	smallBoxes = {}
	for i=1, 3 do
	local box = {}
	box.width = 103
	box.height = 103
		if i == 1 or i == 2  or i == 3 then  -- first row
		box.x = i * (box.width + 10) + (windowWidth/2 - bigBox.width/2 + 10)
		box.y = windowHeight/2 - bigBox.height/2 + 10
		end
	table.insert(smallBoxes, box)
	end

	textDisplay = ""
	gameState = 'start'
end

function love.update(dt)
end


function love.mousepressed(x, y)
	local inside_small_boxes = false
	for i, v in ipairs(smallBoxes) do
		if CheckCollision(x, y, 0, 0, v.x, v.y, v.width, v.height) then
			inside_small_boxes = true
			break
		end
	end

	if inside_small_boxes then
		if gameState == 'start' then gameState = 'play' end
		textDisplay = 'You have clicked inside one of the small boxes'
	else
		textDisplay = ''
	end
end
   

   
function love.draw()
	-- draw the big box
	love.graphics.setColor(200, 200, 60, 255)
	love.graphics.rectangle('line', bigBox.x, bigBox.y, bigBox.width, bigBox.height)
	-- draw the small boxes
	love.graphics.setColor(130, 95, 250, 255)
	for i,b in ipairs(smallBoxes) do
	  love.graphics.rectangle('fill', b.x, b.y, b.width, b.height)
	end
	-- game communucation with players
	love.graphics.setColor(0, 255, 255, 255)
	love.graphics.print(": "..textDisplay, 20, 540)
   end
   
   
   
function CheckCollision(ax1,ay1,aw,ah, bx1,by1,bw,bh)
local ax2,ay2,bx2,by2 = ax1 + aw, ay1 + ah, bx1 + bw, by1 + bh
return ax1 < bx2 and ax2 > bx1 and ay1 < by2 and ay2 > by1
end

[CanYouReply]

Thanks '4vZEROv'. Now it is showing click events inside as well as outside the small boxes. Perfect. I never thought to write the code in mouse pressed function and check. I was writing in update function. Thanks a lot.

Code: Select all

function love.mousepressed(x, y)
	local inside_small_boxes = false
	for i, v in ipairs(smallBoxes) do
		if CheckCollision(x, y, 0, 0, v.x, v.y, v.width, v.height) then
			inside_small_boxes = true
			break
		end
	end

	if inside_small_boxes then
		if gameState == 'start' then gameState = 'play' end
		textDisplay = 'You have clicked inside one of the small boxes'
	else
		textDisplay = 'You have clicked outside small boxes'  -- this text is added here
	end
end