base setup

1 files changed, 118 insertions, 0 deletions

diff --git a/camera.lua b/camera.lua
new file mode 100644
index 0000000..752b32e
--- /dev/null
+++ b/camera.lua
@@ -0,0 +1,118 @@
+local Camera = {}
+Camera.__index = Camera
+
+function Camera:new(target, width, height, mouseFollow, screenToWorldScale)
+    local self = setmetatable({}, Camera)
+    self.target = target
+    self.width = width
+    self.height = height
+    self.mouseFollow = mouseFollow or false
+    self.mouseRadius = math.min(self.width, self.height) * 0.35
+    self.mouseWeight = 0.1
+    self.screenToWorldScale = screenToWorldScale 
+
+    self.x = target.x + (target.width) / 2 - self.width / 2
+    self.y = target.y + (target.height) / 2 - self.height / 2
+
+    self.vx = 0
+    self.vy = 0
+
+    self.stiffness = 50
+    self.damping = 2 * math.sqrt(self.stiffness)
+
+    self.limits = {
+        maxX = nil,
+        minX = nil,
+        maxY = nil,
+        minY = nil,
+    }
+
+    return self
+end
+
+function Camera:setTarget(target)
+    self.target = target
+end
+
+function Camera:setLimits(minX, maxX, minY, maxY)
+  self.limits.minX = minX
+  self.limits.maxX = maxX
+  self.limits.minY = minY
+  self.limits.maxY = maxY
+end
+
+function Camera:update(dt)
+    if not self.target then return end
+    local cx = self.target.x + (self.target.width or 0) / 2
+    local cy = self.target.y + (self.target.height or 0) / 2
+    local targetX = cx - self.width / 2
+    local targetY = cy - self.height / 2
+    
+    if self.mouseFollow then
+        local sw = love.graphics.getWidth()
+        local sh = love.graphics.getHeight()
+        local mx, my = love.mouse.getPosition()
+
+        local offsetX = (mx - sw / 2) * self.screenToWorldScale
+        local offsetY = (my - sh / 2) * self.screenToWorldScale
+
+        local dist = offsetX * offsetX + offsetY * offsetY
+        if dist > self.mouseRadius * self.mouseRadius then
+            local inv = self.mouseRadius / math.sqrt(dist)
+            offsetX = offsetX * inv
+            offsetY = offsetY * inv
+        end
+
+        targetX = targetX + offsetX * self.mouseWeight
+        targetY = targetY + offsetY * self.mouseWeight
+    end
+
+    local accelerationX = (targetX - self.x) * self.stiffness - self.vx * self.damping
+    local accelerationY = (targetY - self.y) * self.stiffness - self.vy * self.damping
+
+    self.vx = self.vx + accelerationX * dt
+    self.vy = self.vy + accelerationY * dt
+
+    self.x = self.x + self.vx * dt
+    self.y = self.y + self.vy * dt
+
+    local lim = self.limits
+    if lim.minX ~= nil then self.x = math.max(lim.minX, self.x) end
+    if lim.maxX ~= nil then self.x = math.min(self.x, lim.maxX - self.width) end
+    if lim.minY ~= nil then self.y = math.max(lim.minY, self.y) end
+    if lim.maxY ~= nil then self.y = math.min(self.y, lim.maxY - self.height) end
+end
+
+function Camera:set(padding)
+  padding = padding or 0
+  love.graphics.push()
+
+  local canvasW = love.graphics.getCanvas():getWidth()
+  local canvasH = love.graphics.getCanvas():getHeight()
+
+  local viewW = self.width + padding * 2
+  local viewH = self.height + padding * 2
+
+  local scaleX = canvasW / viewW
+  local scaleY = canvasH / viewH
+
+  local scale = math.floor(math.min(scaleX, scaleY))
+
+  love.graphics.scale(scale)
+
+  local snapX = math.floor(self.x)
+  local snapY = math.floor(self.y)
+  love.graphics.translate(-(snapX - padding), -(snapY - padding))
+end
+
+function Camera:unset()
+  love.graphics.pop()
+end
+
+function Camera:getSubPixelOffset()
+  local dx = self.x - math.floor(self.x)
+  local dy = self.y - math.floor(self.y)
+  return dx, dy
+end
+
+return Camera
\ No newline at end of file