Snapping mouse to grid

main.lua

@@ -12,21 +12,35 @@ function love.load()
         GridPoint:new( 3, 3 ),
         Color.red
     )
-    line:push( GridPoint:new( 1, 2 ) )
-    line:push( GridPoint:new( 1, 3 ) )
-    line:push( GridPoint:new( 2, 3 ) )
-    line:push( GridPoint:new( 2, 2 ) )
-    line:push( GridPoint:new( 2, 1 ) )
-    line:push( GridPoint:new( 3, 1 ) )
-    line:push( GridPoint:new( 3, 2 ) )
-    line:push( GridPoint:new( 3, 3 ) )
     gameGrid:push( line )
+    mouse = {
+        x = 0,
+        y = 0,
+        pressed = false,
+        lastPressed = false
+    }
 end
 
+-- TODO: move input interactions into module
 function love.update( dt )
-    
+    mouse.x, mouse.y = love.mouse.getPosition()
+    mouse.lastPressed = pressed
+    mouse.pressed = love.mouse.isDown( 1 )
 end
 
 function love.draw()
     gameGrid:draw()
+
+    if mouse.pressed then
+        local x, y = snapCoords( Point:new( mouse.x, mouse.y ) ):coords()
+        local text = string.format( "%d:%d global\n%d:%d local", mouse.x, mouse.y, x, y )
+        love.graphics.print( text, 64, 256 )
+    end
+end
+
+-- Returns local coords from global
+function snapCoords( point )
+    local x = math.ceil( point.x / Config.cellSize )
+    local y = math.ceil( point.y / Config.cellSize )
+    return GridPoint:new( x, y )
 end