HUMP - yet another set of helpers

[HaftSwimmingly]

For room one you did self:whatever it should be room1:whatever.

Thanks

[alundaio]

Hello, I'm wondering if anyone can help me out. I'm using hump.camera and I want to know how I can lock the camera inside the level map boundary; I need a solution that also considers camera scale. Hump.camera has a lockWindow method but it does the opposite, it only moves the camera when the position (such as player) is outside of this bounding box. I want the camera bounding box to stay within the level x,y,w and h. I'm using STI for tiled maps, with a basic 64x64 grid.

I know I can just lock x and y when the player moves near the borders but this don't work when I scale the camera from 1x to 2x.

[ivan]

Hey Akundaio, the math behind it would be fairly simple.
You want to contain one rectangle (the camera's viewport) inside another rectangle (bounds of the map).
The easiest approach is to transform the camera rect in world coords.
Assuming the center of the camera is in world coords:

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local s = 1/camera.zoom -- zoom or scale of the camera
local vw, wh = camera.w, camera.h -- dimensions of the viewport (in screen coords)
local wvw, wvh = vw*s, vh*s -- dimensions of the viewport (in world coords)

Next you clamp the transformed viewport rect to the map bounds:

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camera.x = math.max(camera.x, map.left + wvw)
camera.x = math.min(camera.x, map.right - wvw)
camera.y = math.max(camera.y, map.top + wvh)
camera.y = math.min(camera.y, map.bottom - wvh)

[alundaio]

Ah, I see what I was doing wrong after looking at your example. This is the solution that worked in my case:

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			local wvw, wvh = windowWidth/(2*cam.scale), windowHeight/(2*cam.scale)
			
			cam.x = math.clamp(cam.x,0+wvw,1024-wvw)
			cam.y = math.clamp(cam.y,0+wvh,map.height*64-wvh)

Thanks for the help, cheers.

[murks]

Hi there.

I tried to create timed level progression using hump.timer but all I get is crashes. Any idea what's wrong?

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Timer = require("lib/hump.timer")

function love.load()
	love.graphics.setColor(0,0,0)
	love.graphics.setBackgroundColor(255,255,255)
	TIMERS = {}
	TI = 1
	Timer.every(TI, function() addTimer(TI); TI = TI + 1 end)  
end

function love.update(dt)
	Timer.update(dt)
	for k,v in pairs(TIMERS) do
		TIMERS[k].update(dt)
	end
end

function love.draw()
end

function addTimer(ti)
	local tmpt = Timer.new()
	tmpt.every(ti, print("Timer: "..ti))
	table.insert(TIMERS, ti, tmpt)
end

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Timer: 1
Error: lib/hump/timer.lua:62: attempt to call upvalue 'func' (a nil value)
stack traceback:
	lib/hump/timer.lua:62: in function 'after'
	lib/hump/timer.lua:44: in function 'update'
	main.lua:15: in function 'update'
	[string "boot.lua"]:463: in function <[string "boot.lua"]:435>
	[C]: in function 'xpcall'

[vrld]

Code: Select all

tmpt.every(ti, print("Timer: "..ti))

will not work, because print("Timer: "..ti) is not a function. The correct usage would be

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tmpt.every(ti, function() print("Timer: "..ti) end)

In any case, here is what you are doing right now:

• Every second, add a Timer instance, for which:
  • Every two (three, four, ...) seconds, print the text "Timer: {number}" to the console

After one second, you will have one timer to add timers, and one timer that prints every two seconds. After two seconds, you will have one timer that adds timers and two timers that print to the console every two and three seconds. After three seconds, you will have one timer that adds timers and three timers that print to the console every two, three and four seconds, etc.

Is that what you intended to do?

[murks]

Yes, I intended to spawn increasingly more enemies in a sort-of random time interval. This was the way I came up with (if you replace print with spawn, adjust time intervals to taste).
Is there a better way to do something like that?

[vrld]

Timer.script is great for things like this. For example:

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Timer.script(function(wait)
  local time_passed = 0
  while true do -- replace with terminating condition
    for i = 1,getNumberOfEnemies(time_passed) do
        spawnEnemy()
    end
    
    local time_to_wait = getWaitTime(time_passed)
    wait(time_to_wait)
    time_passed = time_passed + time_to_wait
  end
end

[Rishavs]

Hi

I need some help with camera coordinates.

I am using Hump for the camera and STI for the tilemap.

In Tiled I have added a object called startPoint (where i want my sprite to spawn). The x,y value that i get from Tiled is 320, 2880.

I am simply unable to use this value to spawn the spite. It always spawns somewhere else. I tried using self.cam:worldCoords but the value is again different from what I expected. Manually i can see I need to place the sprite at 708, 1602
Can someone please help me here? Is there a problem with using hump.Camera and STI together?

I am essentially doing this;

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for k, object in pairs(self.map.objects) do
        if object.name == "startPoint" then
            startPointX, startPointY = self.cam:worldCoords(object.x, object.y)
            print("startpoint", object.x, object.y)
        elseif object.name == "endPoint" then
            endPointX, endPointY = self.cam:cameraCoords(object.x, object.y)
--            print("endpoint", object.x, object.y)
        end
    end

and I am drawing the spite like this;

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    self.map:draw()

    love.graphics.draw(img,  startPointX, startPointY, 0, 1, 1, imgWidth / 2, imgHeight / 2)

My code is at;
https://github.com/rishavs/RoguishLove
The relevant code is in the _state_Game.lua file around lines 61 and 117.

[Kibita]

I dont know what's going on with my Timer, it should make my obstacles doing a smooth oscillation in the X axis, but they go crazy, oscillating very fast gradually. That's the code:

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    if self.type == "oscillator-x" then
        obstacleTimer.script(function(wait)
            while true do
                obstacleTimer.tween(7, self, {distFromMid = 100}, "in-linear", function()
                    obstacleTimer.tween(7, self, {distFromMid = 400}, "in-linear") -- const.gameWidth / 2
                end) -- self.radius
                wait(1)
            end
        end)
    end

Should I post more code, or the entire .lua file?