function - ある物理体が別の物理体の衝突を無効にする方法を教えてください。

Question

画面上に A と B と呼ばれるオーバーラップする 2 つの画像があります。ユーザーが画面上を移動できる C と呼ばれる 3 番目の画像があります。2 つのうち大きい方 (A) は、衝突時に C をスポーン ポイントにリセットします。Cが画像Bの上を歩き、スポーンポイントにリセットされないようにする方法を知る必要があります。画像 B のように、画像 A にオーバーラップし、衝突関数を無効にします。

コードは次のとおりです。

--Hides status bar from top of page
display.setStatusBar( display.HiddenStatusBar )

--Set a test background image 
local backgroundimg = display.newImageRect("testbackground.png", 320,576)
backgroundimg.x = display.contentWidth*0.5
backgroundimg.y = display.contentHeight*0.5

--Set the position and amount of score and lives

local score = 0
local lives = 5

local showscore = display.newText("Score: "..score,0,-36,native.systemFont,25)
showscore:setTextColor(0, 0, 0)

local showlives = display.newText("Lives: "..lives,230,-36,native.systemFont,25)
showlives:setTextColor(0, 0, 0)

--Set physics for collisions, etc.
physics = require("physics")
physics.start()
physics.setGravity(0,0)

--set water
local water = display.newImageRect("water.png",320,192)
water.x = display.contentWidth*0.5
water.y = 144
physics.addBody(water,"static")
water:addEventListener("collision", function()timer.performWithDelay(50,waterCollide)end)

function waterCollide(event)
    lives = lives - 1
    display.remove(frog)
    frog = display.newImageRect("FrogTest.png",32,48)
    frog.x = display.contentWidth*0.5
    frog.y = 504
    physics.addBody(frog, "dynamic")
    frog.isFixedRotation = true
end

--Sets buttons images and positions
local forward = display.newImageRect("Forward Button.png",106,100)
forward.x = 160
forward.y = 478

local left = display.newImageRect("Left Button.png",106,100)
left.x = 53
left.y = 478

local right = display.newImageRect("Right Button.png",106,100)
right.x = 267
right.y = 478

--Set log position and movement
local log1 = display.newImageRect("log1.png", 96, 48)
log1.x = 32
log1.y = 226
physics.addBody(log1,"kinematic")
transition.to(log1, {time = 3500, x = 288})


--Set a frog sprite on the screen
frog = display.newImageRect("FrogTest.png",32,48)
frog.x = display.contentWidth*0.5
frog.y = 504
physics.addBody(frog, "dynamic",{density = 1.0, friction = 1, bounce = -1})
frog.isFixedRotation = true

--Sets motion variables
local motionX = 0
local motionY = 0
local speed = 4

--Moving forward
function forward:touch()
    motionX = 0
    motionY = -speed
end
forward:addEventListener("touch",forward)

--Moving Right
function right:touch()
    motionX = speed
    motionY = 0
end
right:addEventListener("touch",right)

--Moving left
function left:touch()
    motionX = -speed
    motionY = 0
end
left:addEventListener("touch",left)

--Moves Frog each time frame is called
function movefrog (event)
    frog.x = frog.x + motionX
    frog.y = frog.y + motionY
end
Runtime:addEventListener("enterFrame", movefrog)

--Stops frog from moving continuously 
local function stop (event)
    if event.phase == "ended" then
        motionX = 0
        motionY = 0
    end
end
Runtime:addEventListener("touch", stop)

--Making sure the frog does not go off the screen
local function stopfrog (event)
    if frog.x <= 16 then
        frog.x = 16
    end
    if frog.x >= 304 then
        frog.x = 304
    end
end
Runtime:addEventListener("enterFrame", stopfrog)