editor: don't allow entities on top of one another

There are still workarounds for when this is actually desirable.

2 files changed, 6 insertions, 1 deletions

diff --git a/editor/draw.cpp b/editor/draw.cpp
index 9060f865..aa8cc5f0 100644
--- a/editor/draw.cpp
+++ b/editor/draw.cpp
@@ -20,6 +20,7 @@ void app::draw_cursor()
 {
     constexpr float LINE_WIDTH = 2;
     auto& shader = M->shader();
+    auto& w = M->world();
     const auto inactive_color = 0xff00ffff_rgbaf;
 
     if (cursor.tile && !cursor.in_imgui)
@@ -56,6 +57,9 @@ void app::draw_cursor()
                 auto [_f, _w, anim_mesh] = M->meshes();
                 const auto offset = Vector3i(Vector2i(sel.offset), 0);
                 const auto pos = cursor.tile->to_signed3()*iTILE_SIZE + offset;
+                auto [ch, t] = w[*cursor.tile];
+                if (!ch.can_place_entity(sel, cursor.tile->local()))
+                    shader.set_tint({1, 0, 1, 0.5f});
                 anim_mesh.draw(shader, *sel.atlas, sel.r, sel.frame, Vector3(pos), 1);
             }
         }
diff --git a/editor/editor.cpp b/editor/editor.cpp
index 1b0611e1..a1de4b4f 100644
--- a/editor/editor.cpp
+++ b/editor/editor.cpp
@@ -110,7 +110,8 @@ void editor::on_click_(world& world, global_coords pos, button b)
             default: break;
             case button::place:
                 if (const auto& sel = mode->get_selected())
-                    mode->place_tile(world, pos, sel, *_app);
+                    if (auto [ch, t] = world[pos]; ch.can_place_entity(sel.proto, pos.local()))
+                        mode->place_tile(world, pos, sel, *_app);
                 break;
             case button::remove:
                 mode->place_tile(world, pos, {}, *_app);