it works

config.lua

@@ -1,5 +1,5 @@
 Config = {
-    cellSize = 64,
+    cellSize = 32,
     gridOffset = 0,
     portWidth = 16
 }

gridpoint.lua

@@ -9,7 +9,7 @@ GridPoint = Point
 ---@return Point
 function GridPoint:absolute()
     return Point:new(
-        self.x * Config.cellSize + Config.gridOffset,
+        self.x * Config.cellSize,
         self.y * Config.cellSize
     )
 end
@@ -17,15 +17,15 @@ end
 -- Same as coords, but converted to global coords
 ---@return number, number
 function GridPoint:globalCoords()
-    return self.x * Config.cellSize - Config.cellSize / 2 + Config.gridOffset,
-    self.y * Config.cellSize - Config.cellSize / 2
+    return self.x * Config.cellSize,
+    self.y * Config.cellSize
 end
 
 -- Returns local coords from global
 ---@param point Point
 ---@return GridPoint
 function GridPoint.snapCoords( point )
-    local x = math.ceil( (point.x - Config.gridOffset) / Config.cellSize )
+    local x = math.ceil( (point.x) / Config.cellSize )
     local y = math.ceil( point.y / Config.cellSize )
     return GridPoint:new( x, y )
 end

main.lua

@@ -3,20 +3,55 @@ require 'gridpoint'
 require 'mouse'
 require 'mechanism'
 require 'port'
+require 'tablefuncs'
 
 function love.load()
     Screenw, Screenh = love.window.getMode()
     Gridw, Gridh = Screenw / Config.cellSize, Screenh / Config.cellSize
-    local port = Port:new( GridPoint:new(-1, 0), PortRotation.left, { 0.8, 0.8, 0, 1 } )
-    Mecha1 = Mechanism:new( GridPoint:new(5, 5), GridPoint:new(3, 3), { port }, {0.5, 0.5, 0.5, 1} )
+    local port1 = Port:new( GridPoint:new(-1, 0), PortRotation.left, { 0.8, 0.8, 0, 1 } )
+    local port2 = Port:new( GridPoint:new(0, -1), PortRotation.up, { 0.8, 0, 0.8, 1 } )
+    local port3 = Port:new( GridPoint:new(3, 2), PortRotation.right, { 0.8, 0, 0, 1 } )
+    local port4 = Port:new( GridPoint:new(2, 3), PortRotation.down, { 0, 0, 0.8, 1 } )
+    local mecha1 = Mechanism:new( GridPoint:new(5, 5), GridPoint:new(3, 3), { port1, port2, port3, port4 }, {0.5, 0.5, 0.5, 1} )
+
+    local port5 = Port:new( GridPoint:new(-1, 0), PortRotation.left, { 0.8, 0.8, 0, 1 } )
+    local port6 = Port:new( GridPoint:new(0, -1), PortRotation.up, { 0.8, 0, 0.8, 1 } )
+    local port7 = Port:new( GridPoint:new(2, 1), PortRotation.right, { 0.8, 0, 0, 1 } )
+    local port8 = Port:new( GridPoint:new(1, 2), PortRotation.down, { 0, 0, 0.8, 1 } )
+    local mecha2 = Mechanism:new( GridPoint:new(10, 5), GridPoint:new(2, 2), { port5, port6, port7, port8 }, {0.5, 1, 0.5, 1} )
+
+    local port9 = Port:new( GridPoint:new(-1, 0), PortRotation.left, { 0.8, 0.8, 0, 1 } )
+    local port10 = Port:new( GridPoint:new(0, -1), PortRotation.up, { 0.8, 0, 0.8, 1 } )
+    local port11 = Port:new( GridPoint:new(2, 0), PortRotation.right, { 0.8, 0, 0, 1 } )
+    local port12 = Port:new( GridPoint:new(1, 1), PortRotation.down, { 0, 0, 0.8, 1 } )
+    local mecha3 = Mechanism:new( GridPoint:new(13, 5), GridPoint:new(2, 1), { port9, port10, port11, port12 }, {1, 0.5, 0.5, 1} )
+
+    local port13 = Port:new( GridPoint:new(-1, 0), PortRotation.left, { 0.8, 0.8, 0, 1 } )
+    local port14 = Port:new( GridPoint:new(0, -1), PortRotation.up, { 0.8, 0, 0.8, 1 } )
+    local port15 = Port:new( GridPoint:new(2, 0), PortRotation.right, { 0.8, 0, 0, 1 } )
+    local port16 = Port:new( GridPoint:new(1, 1), PortRotation.down, { 0, 0, 0.8, 1 } )
+    local mecha4 = Mechanism:new( GridPoint:new(16, 5), GridPoint:new(2, 1), { port13, port14, port15, port16 }, {0.5, 0.5, 1, 1} )
+    Mechs = {mecha1, mecha2, mecha3, mecha4}
 end
 
 function love.update( dt )
     dt = dt
     Mouse:update()
+
+    if Mouse.lastPressed and not Mouse.pressed then
+        local index = TableFind(Mechs, Mouse.point, function(mp, mech)
+            return mp.x >= mech.position.x and mp.x < mech.position.x + mech.size.x and
+                mp.y >= mech.position.y and mp.y < mech.position.y + mech.size.y
+        end
+        )
+        if index ~= nil then
+            Mechs[index]:rotateClockwise()
+        end
+    end
 end
 
 function love.draw()
+    love.graphics.setColor(1, 1, 1, 1)
     for i = 1, Gridw do
         love.graphics.line( i * Config.cellSize, 0, i * Config.cellSize, Screenh )
     end
@@ -24,10 +59,12 @@ function love.draw()
         love.graphics.line( 0, j * Config.cellSize, Screenw, j * Config.cellSize )
     end
     local mx, my = Mouse.point:globalCoords()
-    mx = mx - Config.cellSize / 2
-    my = my - Config.cellSize / 2
     local mh, mw = Config.cellSize, Config.cellSize
     love.graphics.rectangle("fill", mx, my, mh, mw)
 
-    Mecha1:draw()
+    love.graphics.print(string.format("%s, %s", Mouse.point.x, Mouse.point.y), 100, 100)
+
+    for _, mech in ipairs(Mechs) do
+      mech:draw()
+    end
 end

mechanism.lua

@@ -6,19 +6,26 @@ require 'port'
 ---@param size GridPoint
 ---@return GridPoint
 local function nextxcorner( xcorner, size )
-    local cornerLookup = {
+    -- We're looking for old size
+    local cornerLookup1 = {
+        GridPoint:new( 0, 0 ),
+        GridPoint:new( size.y - 1, 0 ),
+        GridPoint:new( size.y - 1, size.x - 1 ),
+        GridPoint:new( 0, size.x - 1 )
+    }
+    local cornerLookup2 = {
         GridPoint:new( 0, 0 ),
         GridPoint:new( size.x - 1, 0 ),
         GridPoint:new( size.x - 1, size.y - 1 ),
-        GridPoint:new( size.x - 1, size.y - 1 )
+        GridPoint:new( 0, size.y - 1 )
     }
-    local index = TableFind(cornerLookup, xcorner, function(value) value:equals(xcorner) end)
-    if index < #cornerLookup then
+    local index = TableFind(cornerLookup1, xcorner, function(xc, value) return value:equals(xc) end)
+    if index < #cornerLookup1 then
         index = index + 1
     else
         index = 0
     end
-    return cornerLookup[index]
+    return cornerLookup2[index]
 end
 
 ---@class Mechanism
@@ -49,6 +56,7 @@ function Mechanism:new( position, size, ports, color )
 end
 
 function Mechanism:rotateClockwise()
+    self.size = GridPoint:new(self.size.y, self.size.x)
     self.xcorner = nextxcorner(self.xcorner, self.size)
     for _, port in ipairs(self.ports) do
         port:rotateClockwise()
@@ -58,8 +66,6 @@ end
 function Mechanism:draw()
     love.graphics.setColor(self.color)
     local x, y = self.position:globalCoords()
-    x = x - Config.cellSize / 2
-    y = y - Config.cellSize / 2
     local w, h = self.size:globalCoords()
     love.graphics.rectangle("fill", x, y, w, h)
     for _, port in ipairs(self.ports) do

mouse.lua

@@ -6,14 +6,19 @@
 Mouse = {
     x = 0,
     y = 0,
-    point = GridPoint:new( 0, 0 )
+    point = GridPoint:new( 0, 0 ),
+    pressed = false,
+    lastPressed = false
 }
 
 -- TODO: fix collision with other line's endpoint
 function Mouse:update()
+    Mouse.lastPressed = Mouse.pressed
     Mouse.x, Mouse.y = love.mouse.getPosition()
-    Mouse.x = Mouse.x + 1
-    Mouse.y = Mouse.y + 1
+    Mouse.x = Mouse.x - Config.cellSize
+    Mouse.y = Mouse.y - Config.cellSize
 
     Mouse.point = GridPoint.snapCoords( Point:new( Mouse.x, Mouse.y ) )
+    
+    Mouse.pressed = love.mouse.isDown( 1 )
 end

port.lua

@@ -48,23 +48,24 @@ function Port:new(position, rotation, color)
 end
 
 function Port:rotateClockwise()
-    local swap = self.position.x
-    self.position.x = -self.position.y
-    self.position.y = swap
-    self.scanOffset = (self.scanOffset == 1) == self.alignment and 1 or 0
+    self.position.x, self.position.y = -self.position.y, self.position.x
+    self.scanOffset = (self.scanOffset == 1) ~= self.alignment and 1 or 0
     self.alignment = not self.alignment
 end
 
 ---@param offset GridPoint
 function Port:draw( offset )
     love.graphics.setColor(self.color)
+    local sox = self.alignment and 0 or self.scanOffset
+    local soy = self.alignment and self.scanOffset or 0
+    
     local drawPoint = GridPoint:new(
-        offset.x + self.position.x + self.scanOffset,
-        offset.y + self.position.y + self.scanOffset
+        offset.x + self.position.x + sox,
+        offset.y + self.position.y + soy
     )
     local x, y = drawPoint:globalCoords()
-    x = self.alignment and x - Config.cellSize / 2 or x - Config.portWidth / 2 - Config.cellSize / 2
-    y = self.alignment and y - Config.portWidth / 2 - Config.cellSize / 2 or y - Config.cellSize / 2
+    x = self.alignment and x or x - Config.portWidth / 2
+    y = self.alignment and y - Config.portWidth / 2 or y
     local w = self.alignment and Config.cellSize or Config.portWidth
     local h = self.alignment and Config.portWidth or Config.cellSize
     love.graphics.rectangle("fill", x, y, w, h)