Collisions

[reaproop17]

Im attempting to make an adventure game where there is walls the player can collide with
How can i make it where the player simply does not go through the wall?

[ivan]

Unfortunately, collisions is not something you can bodge,
so "love.physics" is probably the best way to go.
If you're really adventurous, check out:
http://2dengine.com/doc/gs_collision.html

[D0NM]

1. Lets make the player moving smooth at any PC / at any FPS
use love.update(dt)
I've added widths and heights to the player & wall.

Code: Select all

function love.load()
  gameover = false
  gamewin = false
  player = {}
  player.x = 100
  player.y = 100
  player.width = 20
  player.height = 16
  player.speed = 20
  
  wall = {}
  wall.x = 0
  wall.y = 30
  wall.width = 30
  wall.height = 300
end

function love.update(dt)
  player.sx = 0 --speed by X
  player.sy = 0 --speed by Y

  if love.keyboard.isDown("left") then
      player.sx = -player.speed * dt
  end

  if love.keyboard.isDown("right") then
      player.sx = player.speed * dt
  end

  if love.keyboard.isDown("up") then
      player.sy = - player.speed * dt
  end

  if love.keyboard.isDown("down") then
      player.sy = player.speed * dt
  end
  player.x = player.x + player.sx
  player.y = player.y + player.sy
end

function love.draw()      
  --draw wall
  love.graphics.setColor(127, 127, 64)
    love.graphics.rectangle("fill", wall.x, wall.y, wall.width, wall.height)
  --draw player
  love.graphics.setColor(0, 255, 255)
    love.graphics.rectangle("fill", player.x, player.y, player.width, player.height)

end

lets make your player check for collisions

Code: Select all

local function CheckCollision(x1,y1,w1,h1, x2,y2,w2,h2)
    return x1 < x2+w2 and
            x2 < x1+w1 and
            y1 < y2+h2 and
            y2 < y1+h1
end

function love.load()
  gameover = false
  gamewin = false
  player = {}
  player.x = 160
  player.y = 100
  player.width = 20
  player.height = 16
  player.speed = 80
  
  wall = {}
  wall.x = 60
  wall.y = 30
  wall.width = 30
  wall.height = 300
end

function love.update(dt)
  player.sx = 0 --speed by X
  player.sy = 0 --speed by Y

  if love.keyboard.isDown("left") then
      player.sx = -player.speed * dt
  end

  if love.keyboard.isDown("right") then
      player.sx = player.speed * dt
  end

  if love.keyboard.isDown("up") then
      player.sy = - player.speed * dt
  end

  if love.keyboard.isDown("down") then
      player.sy = player.speed * dt
  end

   --use loops FOR to check it for many walls at once
  --make some table... e.g.  obstacles = {}
  --then add all walls in there:  obstacles[1] = wall;  obstacles[2] = tree;  etc
  --add here a loop
  
  --check collisions
  if not CheckCollision(player.x + player.sx, player.y, player.width, player.height, 
                  wall.x, wall.y, wall.width, wall.height)
  then
 	 player.x = player.x + player.sx
  end
  if not CheckCollision(player.x, player.y + player.sy, player.width, player.height, 
                  wall.x, wall.y, wall.width, wall.height)
  then
	player.y = player.y + player.sy 
 end

end

function love.draw()      
  --draw wall
  love.graphics.setColor(127, 127, 64)
    love.graphics.rectangle("fill", wall.x, wall.y, wall.width, wall.height)
  --draw player
  love.graphics.setColor(0, 255, 255)
    love.graphics.rectangle("fill", player.x, player.y, player.width, player.height)

end

this goes as yer homework
--use loops FOR to check it for many walls at once
--make some table... e.g. obstacles = {}
--then add all walls in there: obstacles[1] = wall; obstacles[2] = tree; etc
--add here a loop