Very new to game development and Lua in general here. I'm making a platformer, and I want to be able to restart the game once a character collides with a certain object, and show a title before that. I also want to reset the character's position back to 0,0 once that happens, but I don't know how.
I made a global variable called WIN that's set to true if the character collides with the object, which works, but then going into my love.draw() function, I have this:
function love.draw()
-- begin virtual resolution drawing
push:apply('start')
-- clear screen using Mario background blue
love.graphics.clear(108/255, 140/255, 255/255, 255/255)
-- renders our map object onto the screen
love.graphics.translate(math.floor(-map.camX + 0.5), math.floor(-map.camY + 0.5))
map:render()
if WIN == true then
love.graphics.printf('NEXT LEVEL', 0, 30, VIRTUAL_WIDTH, 'center')
love.graphics.printf('Continue to Next Level', 0, 45, VIRTUAL_WIDTH, 'center')
love.load()
end
-- end virtual resolution
push:apply('end')
end
When I actually collide with the object, I get the following error:
Error
push.lua:48: love.window.setMode cannot be called while a Canvas is active in love.graphics.
Traceback
[C]: in function 'windowUpdateMode'
push.lua:48: in function 'setupScreen'
main.lua:43: in function 'load'
main.lua:116: in function 'draw'
[C]: in function 'xpcall'
The error lines are in my love.load() function, which is as follows:
function love.load()
-- sets up a different, better-looking retro font as our default
love.graphics.setFont(love.graphics.newFont('fonts/font.ttf', 8))
-- sets up virtual screen resolution for an authentic retro feel
push:setupScreen(VIRTUAL_WIDTH, VIRTUAL_HEIGHT, WINDOW_WIDTH, WINDOW_HEIGHT, {
fullscreen = false,
resizable = true
})
love.window.setTitle('Super Mario 50')
love.keyboard.keysPressed = {}
love.keyboard.keysReleased = {}
end
I'm guessing the issue is that I can't set up screen again after already doing that once, but I don't know how to fix this and create a fresh start. Any help is appreciated!
love.load() runs once. That one time is when your game starts up. Don't call love.load() (or love.update()) within love.draw() or vice versa. The Love2D game engine calls these functions, so you don't call them.
Update the start position within love.update() not love.draw(). love.draw() is only for drawing stuff. I believe it would be the View in a model-view-controller architecture.
To restart the position of your object, you would have to do something like
if WIN == true then
push.x = push.start.x
push.y = push.start.y
map.camX = map.start.camX
map.camY = map.start.camY
end
Or something along those lines, it's hard to know without seeing your variables. Your love.draw() will then draw the things at the coordinates that they are at.
To reset/restart the Game without reloading the executable use:
love.event.quit('restart')
But before doing this make a dark screen before with red dropping letters: GAME OVER
Related
Pardon the noob question, I am new to Roblox LUA.
I am trying to make the humanoid move forwards and backwards, (as when an officer, guards a perimeter by moving to and fro) but there may be something wrong with this script, because it only moves forwards.
local toggle = true
local RunService = game:GetService("RunService")
local humanoid = game.Players.LocalPlayer.Character:WaitForChild("Humanoid")
RunService:BindToRenderStep("Move", Enum.RenderPriority.Character.Value + 1, function()
while toggle do
humanoid:Move(Vector3.new(0, 0, -1), true)
wait(1)
humanoid:Move(Vector3.new(0, 0, 1), true)
wait(1)
end
end)
And then when I toggle = false, it does not stop.
I can't use keypress as it defeats the purpose of what I intend to do.
Thank you for any assistance.
The way this code is structured does not make much sense. You're creating a loop inside a function that is triggered every frame. Every single frame, you create a new loop... After just 10 seconds you might have 300 loops trying to move the humanoid at the same time.
Because the loops constantly overwrite each other, the last one to run takes precedence... Which is likely why it's only towards one direction.
I presume you want to make the character move towards (0,0,-1) for a second, then towards (0,0,1) for another second and then, if toggle is enabled, run again.
What you should be doing instead is not creating a loop inside the BindToRenderStep, but setting the movement every frame according to where the character should be moving to, and running that loop outside, once:
local toggle = true
local RunService = game:GetService("RunService")
local humanoid = game.Players.LocalPlayer.Character:WaitForChild("Humanoid")
movement = nil
RunService:BindToRenderStep("Move", Enum.RenderPriority.Character.Value + 1, function()
if movement then
humanoid:Move(movement, true)
end
end)
while toggle do
movement = Vector3.new(0, 0, -1)
task.wait(1)
movement = Vector3.new(0, 0, 1)
task.wait(1)
end
movement = nil
Mind that this code has some quirks:
Nothing will be able to run after the while, so nothing will realistically set the toggle off if placed after while toggle do. It depends on where you want to switch the toggle how you'd handle this.
Depending on where you've placed this, it might error. If this is in StarterPlayerScripts you should use the CharacterAdded event to wait until the character exists, and then handle setting the humanoid again when respawning (because the humanoid will not be the same one if the character respawns). If this is in StarterCharacterScripts, there is no need to access the LocalPlayer, you can just do script.Parent:WaitForChild("Humanoid") (though it also comes down to personal preference).
You've made the movement relative to the camera with that true argument to :Move() https://create.roblox.com/docs/reference/engine/classes/Humanoid#Move. The player will still be able to move the camera to change how the movement direction.
The devforum was no help so I'm asking it here.
Im trying to make a Five Nights At Freddys game and I’m making the custom camera script, but its not facing the correct direction. Why is this happening?
Video:
https://doy2mn9upadnk.cloudfront.net/uploads/default/original/4X/0/2/4/024cca4de534dcfc084a944d3c2a13abf5382e0c.mp4
Code
RunService.RenderStepped:Connect(function()
if PlayerCharacter:WaitForChild("Player"):WaitForChild("isNightGuard").Value and not game.ReplicatedStorage:FindFirstChild("GameData"):FindFirstChild("inCams").Value then
Mouse.TargetFilter = game.Workspace.NightguardPosition
CurrentCamera.CFrame = CFrame.new(game.Workspace.NightguardPosition.CFrame.Position)
CurrentCamera.CFrame = CFrame.new(CurrentCamera.CFrame.Position, Mouse.UnitRay.Direction * 10)
end
end)
The NightguardPosition part is in the correct position and orientation.
I’ve tried many variations of the camera script but they all have the same result, please help?
The issue here is that for the CFrame.new(Vector3: position, Vector3: lookAt) constructor, the second Vector3 is what the CFrame will point at in world-space and is not a direction vector, unless position is (0, 0, 0), the origin. To fix the issue, you must add NightguardPosition.Position to the where the mouse is pointing in the world since that unit ray of the mouse like an offset when having to set lookAt.
Modified code with some comments (changes made to RenderStepped are suggestions and do not need to be built around!):
CurrentCamera.CameraSubject = workspace.NightguardPosition --// The CameraSubject is the LocalPlayer's Humanoid by default, causing some funky movements. Make sure to revert this
--// when cameras are exited.
--// Small performance improvement, unless this is changed elsewhere. Either way, it is best to only set when necessary and not in a looping behavior.
Mouse.TargetFilter = game.Workspace.NightguardPosition
local nightGuardPos = workspace.NightguardPosition.Position
RunService.RenderStepped:Connect(function()
--// CurrentCamera.CFrame = CFrame.new(game.Workspace.NightguardPosition.CFrame.Position)
--// Can be removed as this is the same as getting the Position of NightguardPosition
CurrentCamera.CFrame = CFrame.new(nightGuardPos, nightGuardPos + Mouse.UnitRay.Direction * 10)
end)
I have a player who is navigating in space. Since it is space, there is not gravity therefore no parabolic trajectory. The player is just going in a horizontal line from left to right. The player is not actually moving, but the background is, so it looks like he is. The x value is fixed.
I have 2 buttons that help the player avoid obstacles like asteroids. One button gives the player upward force, the other one downward force. The following are the functions called when those buttons are pressed.
function moveUp( event )
if event.phase == "ended" then
player:applyForce(0, 8, player.x, player.y)
player:setSequence("jump")
jumpChannel = audio.play(jumpSound)
end
return true
end
function moveDown( event )
if event.phase == "ended" then
player:applyForce(0, -8, player.x, player.y)
player:setSequence("jump")
jumpChannel = audio.play(jumpSound)
end
return true
end
The problem with this implementation is that whenever a force is applied the player keeps going in that direction. Then you have to apply force in the opposite direction and he will keep going in that direction forever. That is not what I want. What I want is :
when UP is pressed, player goes up for certain value (say 50 px) in Y. Then the player keeps going in the horizontal direction from left to right in the new altitude.
When DOWN is pressed, player goes down certain value. Then the player keeps going in the horizontal direction from left to right in the new altitude.
What is the best way to accomplish this? Can I do this using the applyForce function or is there another method? Thanks in advance for your time!
You have to remember that F=ma: if force applied is 0, a is 0, which means velocity does not change. You have two choices:
apply an opposite force that will decrease the speed, and stop when speed is 0. Every Body has myBody.linearDamping factor which you could set to non-zero. If that doesn't work, you can apply your own damping: you make it proportional to Body velocity, so you need an enterFrame event handler that updates the force based on current velocity:
function enterFrame(e)
local v = player:getLinearVelocity()
player:applyForce(- a * v)
end
Here the "a" is damping, some arbitrary number (0 is what you have now; the larger it is, the faster the player will return to 0 velocity). I haven't checked whether the applyForce() is additive (adds to existing forces) or absolute (replaces existing). But you get the idea.
directly move the player:
function moveUp( event )
if event.phase == "ended" then
player:setLinearVelocity(0, 8) -- pixels/sec
You will still need an enterFrame handler to monitor position and setLinearVelocity(0,0) when desired position reached.
You will get smoother, more "realistic" motion with option 1.
Using the Love framework by the way.
Ok, so I'm looking to create a random map generation. I obviously only want it drawn once, so I tried to set up a very basic structure. Which isn't working and I can't figure out why.
function love.load()
testVar = 1
end
function love.draw()
if testVar == 1 then
testFunction()
love.graphics.print("Update", 20, 200)
end
love.graphics.print(testVar, 100, 100)
end
function testFunction()
love.graphics.print("Success", 20, 300)
testVar = 0
end
What that is doing is only printing "0", thanks to the command to print testVar up in the draw function. So it seems that it's updating the testVar value without actually running testFunction. Is this something to do with Lua?
For those unfamiliar with Love, love.draw is called every frame, love.load only initially.
This code works as expected. It's just love.draw is called every frame (multiple times per second), so the output from the first frame is quickly overwritten by next frames. Usually you use love.update when you need to make changes to your state (for example, based on user input) and love.draw to draw that state on the screen (every frame).
For posting reasons here's a simple version of what I'm trying to do.
On the screen I have a simple circle object that is static and doesn't move. The user can then drag and drop a straight line. If the line passes through that circle I'm hoping for the collision event to be triggered.
It appears that unless one of the objects are moving the collision is never detected. Can I detect the collision when the line is drawn?
Collision Event
function onHit(e)
print("hit");
end
Runtime:addEventListener("collision", onHit)
Touch Event
local startX = 0;
local startY = 0;
local endX = 0;
local endY = 0;
function onTouch(e)
if(e.phase == "began") then
startX = e.x
startY = e.y
elseif(e.phase == "moved") then
endX = e.x
endY = e.y
elseif(e.phase == "ended") then
local line = display.newLine(startX, startY, endX, endY)
line:setColor(100, 100, 100)
line.width = 2
physics.addBody(line, "static", { })
end
end
Runtime:addEventListener("touch", onTouch)
Create circle
local c = display.newCircle(50, 50, 24)
physics.addBody(c, "static", { radius = 24 })
This page from the Corona SDK docs describes the bodyType property about halfway down the page. When describing "static" bodies, it says (my emphasis):
static bodies don't move, and don't interact with each other;
examples of static objects would include the ground, or the walls of a
pinball machine.
That means that one of the objects has to be something other than static.
Here's an idea, although I haven't tried it myself: (See update below.) Make the line dynamic when you first create it. Set it to static a few milliseconds later using a timer.performWithDelay function. If a collision event occurs in the meantime, you will know that you've got an overlap, and can set the bodyType back to static immediately. If you don't get a collision event, the bodyType will still be dynamic in the delayed routine, and you'll know you didn't have an overlap. In this case, you'll still need to set the line to static in the delayed routine.
UPDATE: Tested this, using your code as the starting point
I changed the collision event to always set both objects' bodyType to static:
function onHit(e)
print("hit")
e.object1.bodyType = "static"
e.object2.bodyType = "static"
end
Then I changed the addBody call for the line to add it as a dynamic body, with new code to setup a timer.PerformWithDelay function to check after a short time:
physics.addBody(line, "dynamic", { })
timer.performWithDelay(10,
function()
if line.bodyType == "dynamic" then
print ("NO OVERLAP")
line.bodyType = "static"
end
end)
The results were, unfortunately, mixed. It works most of the time, perhaps 95%, but fails occasionally when drawing a line that starts outside the circle and ends inside, which should be an overlap, but is sometimes reported as no overlap. I wasn't able to figure out why this was happening. I'm posting this anyway, hoping that it gets you going, and also thinking that someone may be able to figure out the inconsistent behavior and educate us both.
Failing that, you could add an additional check for the "no overlap" case to check if either endpoint of the line is closer than the radius of the circle away from the center. That would be make things work, but I suppose it misses the whole point of letting the physics engine to the work.
Anyway, good luck!
Perform a raycast when you release your mouse press. This way you can keep both objects static, and know that they intersect via the raycast callback.
(I know that this is an old post, but it was the first hit on my Google search and is incorrect afaic)
Set the body type as kinematic, set it as a sensor, and update its position to the entity it's tied to every frame. Unlike static, kinematic can interact with static.