diff --git a/Makefile b/Makefile
index 3723a40..77b1ba6 100644
--- a/Makefile
+++ b/Makefile
@@ -57,7 +57,7 @@ clean:
 	meson compile --clean -C builddir
 
 debug_test: build
-	gdb --nx -x .gdbinit --ex run --args builddir/runtests -e "[matrix:viewport]"
+	gdb --nx -x .gdbinit --ex run --args builddir/runtests -e
 
 win_installer:
 	powershell 'start "C:\Program Files (x86)\solicus\InstallForge\bin\ifbuilderenvx86.exe" scripts\win_installer.ifp'
diff --git a/tests/textures.cpp b/tests/textures.cpp
index 68391a4..00efb5e 100644
--- a/tests/textures.cpp
+++ b/tests/textures.cpp
@@ -2,26 +2,42 @@
 #include <fmt/core.h>
 #include <string>
 #include "textures.hpp"
-#include "levelmanager.hpp"
+#include "constants.hpp"
+#include "components.hpp"
 
 using namespace fmt;
 
 TEST_CASE("test texture management", "[textures]") {
   components::init();
   textures::init();
+
   auto spider = textures::get("hairy_spider");
   REQUIRE(spider.sprite != nullptr);
   REQUIRE(spider.texture != nullptr);
+  REQUIRE(spider.frame_size.x == TEXTURE_WIDTH);
+  REQUIRE(spider.frame_size.y == TEXTURE_HEIGHT);
 
   auto image = textures::load_image("assets/sprites/hairy_spider.png");
 
-  auto img_ptr = textures::get_surface(0);
-  REQUIRE(img_ptr != nullptr);
+  size_t floor_tile = textures::get_id("floor_tile");
+  size_t gray_stone = textures::get_id("gray_stone_floor_light");
+
+  auto floor_ptr = textures::get_surface(floor_tile);
+  REQUIRE(floor_ptr != nullptr);
+
+  auto gray_stone_ptr = textures::get_surface(gray_stone);
+  REQUIRE(gray_stone_ptr != nullptr);
+
+  auto& light = textures::get_ambient_light();
+  REQUIRE(light.size() > 0);
+  REQUIRE(light[floor_tile] == 0);
+  REQUIRE(light[gray_stone] > 0);
+
+  auto& tiles = textures::get_map_tile_set();
+  REQUIRE(tiles.size() > 0);
+  REQUIRE(tiles[floor_tile] > 0);
+  REQUIRE(tiles[gray_stone] > 0);
 
-  LevelManager levels;
-  GameLevel level = levels.current();
-  auto& tiles = level.map->tiles();
-  auto& walls = level.map->walls();
-  REQUIRE(matrix::width(tiles) == matrix::width(walls));
-  REQUIRE(matrix::height(tiles) == matrix::height(walls));
+  auto ceiling = textures::get_ceiling(floor_tile);
+  REQUIRE(ceiling != nullptr);
 }
diff --git a/textures.cpp b/textures.cpp
index aa297d0..479245a 100644
--- a/textures.cpp
+++ b/textures.cpp
@@ -23,9 +23,14 @@ namespace textures {
 
       int width = settings["frame_width"];
       int height = settings["frame_height"];
-      sprite->setTextureRect({{0,0}, {width, height}});
+      dbc::check(width % 2 == 0,
+          fmt::format("sprite {} has invalid frame size", name));
 
-      TMGR.sprite_textures.try_emplace(name, sprite, texture);
+      sf::Vector2i frame_size{width, height};
+
+      sprite->setTextureRect({{0,0}, frame_size});
+
+      TMGR.sprite_textures.try_emplace(name, sprite, texture, frame_size);
     }
   }
 
@@ -46,6 +51,11 @@ namespace textures {
       auto &config = el.value();
       const std::string& texture_fname = config["texture"];
       size_t surface_i = config["id"];
+
+      dbc::check(!TMGR.name_to_id.contains(el.key()),
+          fmt::format("duplicate key in textures {}",
+            (std::string)el.key()));
+
       TMGR.name_to_id.insert_or_assign(el.key(), surface_i);
 
       if(surface_i >= tiles.size()) {
diff --git a/textures.hpp b/textures.hpp
index 39cc456..5ec9e3f 100644
--- a/textures.hpp
+++ b/textures.hpp
@@ -12,6 +12,7 @@ namespace textures {
   struct SpriteTexture {
     std::shared_ptr<sf::Sprite> sprite = nullptr;
     std::shared_ptr<sf::Texture> texture = nullptr;
+    sf::Vector2i frame_size;
   };
 
   struct TextureManager {