diff --git a/src/WorldTraveller.c b/src/WorldTraveller.c
index 2236b8e..ce57f03 100644
--- a/src/WorldTraveller.c
+++ b/src/WorldTraveller.c
@@ -82,6 +82,9 @@ INTERNAL void rendererInit(GameState *state, v2 windowSize)
 // TODO(doyle): Remove and implement own random generator!
 #include <time.h>
 #include <stdlib.h>
+
+GLOBAL_VAR UiState uiState = {0};
+
 void worldTraveller_gameInit(GameState *state, v2 windowSize)
 {
 	AssetManager *assetManager = &state->assetManager;
@@ -342,6 +345,9 @@ void worldTraveller_gameInit(GameState *state, v2 windowSize)
 #endif
 
 	srand(CAST(u32)(time(NULL)));
+
+	uiState.mouseP      = &state->input.mouse;
+	uiState.mouseIsDown = &state->input.mouseLeft;
 }
 
 INTERNAL inline v4 getEntityScreenRect(Entity entity)
@@ -609,7 +615,6 @@ INTERNAL inline void resetEntityState(World *world, Entity *entity)
 	entity->stats->entityIdToAttack = ENTITY_NULL_ID;
 }
 
-
 INTERNAL registerEvent(EventQueue *eventQueue, enum EventType type, void *data)
 {
 #ifdef DENGINE_DEBUG
@@ -620,6 +625,7 @@ INTERNAL registerEvent(EventQueue *eventQueue, enum EventType type, void *data)
 	eventQueue->queue[currIndex].type = type;
 	eventQueue->queue[currIndex].data = data;
 }
+
 INTERNAL void entityStateSwitch(EventQueue *eventQueue, World *world,
                                 Entity *entity, enum EntityState newState)
 {
@@ -876,7 +882,49 @@ INTERNAL void sortWorldEntityList(World *world, i32 numDeadEntities)
 	world->freeEntityIndex -= numDeadEntities;
 }
 
-UiState uiState = {0};
+INTERNAL b32 pointInRect(Rect rect, v2 point)
+{
+	if (point.x < rect.pos.x || point.x > rect.pos.x + rect.size.w ||
+	    point.y > rect.pos.y + rect.size.h || point.y < rect.pos.y)
+		return FALSE;
+	return TRUE;
+}
+
+i32 button(AssetManager *assetManager, Renderer *renderer, i32 id, Rect rect,
+           v2 mouseP)
+{
+	if (pointInRect(rect, mouseP))
+	{
+		uiState.hotItem = id;
+		if (uiState.activeItem == 0 && uiState.mouseIsDown)
+			uiState.activeItem = id;
+	}
+
+	RenderTex renderTex = renderer_createNullRenderTex(assetManager);
+	renderer_staticRect(renderer, v2_add(V2(8, 8), rect.pos), rect.size,
+	                    V2(0, 0), 0, renderTex, V4(0, 0, 0, 1));
+	if (uiState.hotItem == id)
+	{
+		if (uiState.activeItem == id)
+		{
+			renderer_staticRect(renderer, v2_add(V2(2, 2), rect.pos), rect.size,
+			                    V2(0, 0), 0, renderTex, V4(1, 1, 1, 1));
+		}
+		else
+		{
+			renderer_staticRect(renderer, v2_add(V2(0, 0), rect.pos), rect.size,
+			                    V2(0, 0), 0, renderTex, V4(1, 1, 1, 1));
+		}
+	}
+	else
+	{
+		renderer_staticRect(renderer, v2_add(V2(0, 0), rect.pos), rect.size,
+		                    V2(0, 0), 0, renderTex, V4(0.5f, 0.5f, 0.5f, 1));
+	}
+
+	return 0;
+}
+
 void worldTraveller_gameUpdateAndRender(GameState *state, f32 dt)
 {
 	if (dt >= 1.0f) dt = 1.0f;
@@ -1128,6 +1176,17 @@ void worldTraveller_gameUpdateAndRender(GameState *state, f32 dt)
 	renderer_staticRect(renderer, state->input.mouse, hero->hitboxSize,
 	                    V2(0, 0), 0, nullRenderTex, V4(0.5f, 0, 0, 0.5f));
 
+#if 0
+	RenderTex renderTex = renderer_createNullRenderTex(assetManager);
+	v2 buttonP = V2(500, 500);
+	v2 buttonSize = V2(100, 100);
+	renderer_staticRect(renderer, v2_add(V2(8, 8), buttonP), buttonSize,
+	                    V2(0, 0), 0, renderTex, V4(0, 0, 0, 1));
+#endif
+
+	Rect buttonRect = {V2(500, 500), V2(100, 100)};
+	button(assetManager, renderer, 1, buttonRect, *uiState.mouseP);
+
 	/* Draw hero avatar */
 	TexAtlas *heroAtlas  = asset_getTextureAtlas(assetManager, texlist_hero);
 	v4 heroAvatarTexRect = heroAtlas->texRect[herorects_head];
diff --git a/src/include/Dengine/Math.h b/src/include/Dengine/Math.h
index b1dc035..43b7bdb 100644
--- a/src/include/Dengine/Math.h
+++ b/src/include/Dengine/Math.h
@@ -45,6 +45,12 @@ typedef union v4
 	f32 e[4];
 } v4;
 
+typedef struct Rect
+{
+	v2 pos;
+	v2 size;
+} Rect;
+
 INTERNAL inline v2 V2i(const i32 x, const i32 y)
 {
 	v2 result = {CAST(f32)x, CAST(f32)y};
diff --git a/src/include/Dengine/WorldTraveller.h b/src/include/Dengine/WorldTraveller.h
index 56d3e3c..c5bbd31 100644
--- a/src/include/Dengine/WorldTraveller.h
+++ b/src/include/Dengine/WorldTraveller.h
@@ -15,6 +15,8 @@
 
 typedef struct UiState
 {
+	v2 *mouseP;
+	b32 *mouseIsDown;
 	i32 hotItem;
 	i32 activeItem;
 } UiState;
@@ -53,7 +55,6 @@ typedef struct GameState
 	AssetManager assetManager;
 	AudioManager audioManager;
 	MemoryArena arena;
-	UiState uiState;
 } GameState;
 
 void worldTraveller_gameInit(GameState *state, v2 windowSize);