1 files changed, 62 insertions, 0 deletions
diff --git a/src/phys.lua b/src/phys.lua
index 8cf0613..2b1e101 100644
--- a/src/phys.lua
+++ b/src/phys.lua
@@ -56,6 +56,10 @@ function phys.Box.new(
   self.layers = opts.layers or { "hard" }
   self.mask = opts.mask or {}
 
+  local scene = get_current_scene()
+  assert(scene, "No scene set up.")
+  self.tilemap_mask = opts.tilemap_mask or { scene.tilemap }
+
   self.touchx = 0
   self.touchy = 0
 
@@ -100,10 +104,68 @@ function phys.Box:get_rect()
       self.height
 end
 
+function box_in_tilemap(map, box)
+  local x, y, width, height = box:get_rect()
+
+  local value
+  value = has_tile(map, to_tile_coords(x, y))
+  if has_tile(map, to_tile_coords(x + width, y)) then
+    return true
+  end
+  if has_tile(map, to_tile_coords(x, y + height)) then
+    return true
+  end
+  if has_tile(map, to_tile_coords(x + width, y + height)) then
+    return true
+  end
+
+  local extra_x = math.floor(width / (TILESIZE - 1))
+  local step = width / (extra_x + 1)
+
+  for i = 1, extra_x do
+    if has_tile(
+      map, to_tile_coords(x + step * i, y))
+    then
+      return true
+    end
+
+    if has_tile(
+      map, to_tile_coords(x + step * i, y + height))
+    then
+      return true
+    end
+  end
+
+  local extra_y = math.floor(height / (TILESIZE - 1))
+  step = height / (extra_y + 1)
+
+  for i = 1, extra_y do
+    if has_tile(
+      map, to_tile_coords(x, y + step * i))
+    then
+      return true
+    end
+
+    if has_tile(
+      map, to_tile_coords(x + width, y + step * i))
+    then
+      return true
+    end
+  end
+
+  return value
+end
+
 function collision_check(box)
   local box_x, box_y, box_width, box_height = box:get_rect()
   local other_x, other_y, other_width, other_height
 
+  for _, tilemap in ipairs(box.tilemap_mask) do
+    if box_in_tilemap(tilemap, box) then
+      return true
+    end
+  end
+
   for _, layer in ipairs(box.mask) do
     for _, other in ipairs(world.layers[layer] or {}) do
       if other == box then