I'm in the middle of creating a breakout-style game. The ball is bouncing fine at the moment, but only when the bricks are not moving. When the ball collides with a moving brick, sometimes it will calculate the collision wrong and the ball will end up passing through the brick instead of reflecting off it. Here's some code to see what I mean:
superstrict
type Tball
field x: float
field y: float
field w: float
field h: float
field dx: float
field dy: float
field hit: int
field temp_x: float
field temp_y: float
end type
type Tbrick
field x: float
field y: float
field w: float
field h: float
field dx: float
field dy: float
end type
graphics(800,600,0)
local ball: Tball = new Tball
ball.x = 374
ball.y = 100
ball.w = 16
ball.h = 16
ball.dx = 0
ball.dy = 5
local brick: Tbrick = new Tbrick
brick.x = 350
brick.y = 200
brick.w = 64
brick.h = 32
brick.dx = 0
brick.dy = 1
repeat
' Move Ball X
ball.temp_x = ball.x + ball.dx
if ball.hit = false
if (overlap(ball.temp_x,ball.temp_y,ball.w,ball.h,brick.x,brick.y,brick.w,brick.h))
ball.dx = -ball.dx
ball.hit = true
notify("Horizontal Collision")
ball.temp_x = ball.x
endif
endif
ball.x = ball.temp_x
' Move Ball Y
ball.temp_y = ball.y + ball.dy
if ball.hit = false
if (overlap(ball.temp_x,ball.temp_y,ball.w,ball.h,brick.x,brick.y,brick.w,brick.h))
ball.dy = -ball.dy
ball.hit = true
notify("Vertical Collision")
ball.temp_y = ball.y
endif
endif
ball.y = ball.temp_y
' Bounce ball off walls
if (ball.x > 800 - ball.w or ball.x < 0) ball.dx = -ball.dx ; ball.hit = false
if (ball.y > 600 - ball.h or ball.y < 0) ball.dy = -ball.dy ; ball.hit = false
' Move Brick
brick.x :+ brick.dx
brick.y :+ brick.dy
' Bounce brick off walls
if (brick.x > 800 - (brick.w * 2) or brick.x < brick.w) brick.dx = -brick.dx
if (brick.y > 600 - (brick.h * 2) or brick.y < brick.h) brick.dy = -brick.dy
' Draw
cls
if (ball.hit) drawtext("Hit",0,0)
' Ball
setcolor(255,255,255)
draw_unfilled_rect(ball.x,ball.y,ball.w,ball.h)
' Brick
setcolor(0,255,0)
draw_unfilled_rect(brick.x,brick.y,brick.w,brick.h)
flip
until keydown(KEY_ESCAPE)
end
function draw_unfilled_rect(x: float, y: float, w: float, h: float)
w = (w + x)
h = (h + y)
drawline(x, y, w, y)
drawline(x, h, w, h)
drawline(x, y, x, h)
drawline(w, y, w, h)
end function
function overlap: int(x1: float,y1: float,w1: float,h1: float, x2: float,y2: float,w2: float, h2: float)
if ((x1 + w1) > x2) and ((x1 + w1) < (x2 + (w2 + w1))) and ((y1 + h1) > y2) and ((y1 + h1) < (y2 + (h2 + h1))) return true
end function
How would I fix this code so the ball would bounce off the brick correctly? Thanks in advance.
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