diff --git a/CMakeLists.txt b/CMakeLists.txt
index 4b0e622..dcd672f 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -8,15 +8,15 @@ set(CMAKE_EXPORT_COMPILE_COMMANDS ON)
 string(APPEND resources_dir "${CMAKE_CURRENT_SOURCE_DIR}/data@data")
 
 if (EMSCRIPTEN)
-    set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -Oz -s USE_GLFW=3 -s ASSERTIONS=1 -s WASM=1 -s ASYNCIFY --preload-file ${resources_dir} --shell-file=\"${CMAKE_CURRENT_SOURCE_DIR}/shell.html\"")
+    set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -Oz -s ALLOW_MEMORY_GROWTH=1 -s NO_EXIT_RUNTIME=0 -s USE_GLFW=3 -s ASSERTIONS=1 -s WASM=1 -s ASYNCIFY --preload-file ${resources_dir} --shell-file=\"${CMAKE_CURRENT_SOURCE_DIR}/shell.html\"")
     set(CMAKE_EXECUTABLE_SUFFIX ".html")
 endif ()
 
 file(GLOB_RECURSE PROJECT_SRC src/*.cpp src/*.hpp src/*.h)
 
 find_package(raylib)
-#find_package(spdlog)
+find_package(glm)
 find_package(nlohmann_json)
 
 add_executable(${PROJECT_NAME} ${PROJECT_SRC})
-target_link_libraries(${PROJECT_NAME} raylib nlohmann_json::nlohmann_json)
+target_link_libraries(${PROJECT_NAME} raylib nlohmann_json::nlohmann_json glm::glm)
diff --git a/conanfile.txt b/conanfile.txt
index 2496da6..0d9a6c2 100644
--- a/conanfile.txt
+++ b/conanfile.txt
@@ -4,7 +4,7 @@
 raylib/5.5
 #spdlog/1.15.0
 nlohmann_json/3.11.3
-#glm/cci.20230113
+glm/cci.20230113
 #glfw/3.4
 #glew/2.2.0
 #stb/cci.20240531
diff --git a/data/img2.jpg b/data/img2.jpg
new file mode 100644
index 0000000..4dee48f
Binary files /dev/null and b/data/img2.jpg differ
diff --git a/data/img3.jpg b/data/img3.jpg
new file mode 100644
index 0000000..c756eac
Binary files /dev/null and b/data/img3.jpg differ
diff --git a/data/img4.jpg b/data/img4.jpg
new file mode 100644
index 0000000..a08a6bb
Binary files /dev/null and b/data/img4.jpg differ
diff --git a/src/main.cpp b/src/main.cpp
index 9f92a98..f37a363 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -1,19 +1,128 @@
+#include <algorithm>
+#include <glm/common.hpp>
+#include <glm/ext/vector_uint2.hpp>
+#include <glm/ext/vector_uint3.hpp>
+#include <glm/glm.hpp>
+#include <iostream>
 #include <raylib.h>
+#include <vector>
 
-int main (int argc, char *argv[]) 
+#define MAX_PTS_PER_NODE 1 
+
+struct kdtree
+{
+    kdtree(std::vector<glm::uvec2> &pts)
+    {
+        calc_aabb(pts);
+
+        if (pts.size() > MAX_PTS_PER_NODE)
+        {
+            int split_index = aabb_size.x > aabb_size.y ? 0 : 1;
+            
+            std::sort(pts.begin(), pts.end(),
+                      [split_index](const glm::uvec2 &a, const glm::uvec2 &b) 
+                      {
+                        return a[split_index] < b[split_index]; 
+                      });
+
+            {
+                std::vector<glm::uvec2> lpts(pts.begin(), pts.begin() + pts.size() / 2);
+                left = new kdtree(lpts);
+            }
+
+            {
+                std::vector<glm::uvec2> rpts(pts.begin() + pts.size() / 2, pts.end());
+                right = new kdtree(rpts);
+            }
+        
+        }
+    }
+
+    void draw()
+    {
+        DrawRectangleLines(aabb_min.x, aabb_min.y, aabb_size.x, aabb_size.y, BLACK);
+        if(left && right)
+        {
+            left->draw();
+            right->draw();
+        }
+    }
+    
+    void calc_aabb(const std::vector<glm::uvec2> &pts)
+    {
+        for (const auto &p : pts)
+        {
+            aabb_min = glm::min(aabb_min, p);
+            aabb_max = glm::max(aabb_max, p);
+        }
+
+        aabb_size = aabb_max - aabb_min;
+    }
+
+    kdtree *left = nullptr;
+    kdtree *right = nullptr;
+    glm::uvec2 aabb_min{999999};
+    glm::uvec2 aabb_max{000000};
+    glm::uvec2 aabb_size;
+};
+
+int main (int argc, char *argv[])
 {
     auto img = LoadImage("data/img.jpg");
 
-    InitWindow(img.width, img.height, "");   
+    InitWindow(img.width, img.height, "");
     SetTargetFPS(60);
 
-    while (!WindowShouldClose()) 
+    std::vector<glm::uvec2> pts;
+
+    for (int i = 0; i < img.width * img.height; ++i)
+    {
+        int x = i % img.width;
+        int y = i / img.width;
+
+        auto val = ((glm::u8vec3 *)img.data + i)->r < 10;
+
+        bool found = false;
+        for(int dy = -1; dy <= 1; ++dy)
+        {
+            for(int dx = -1; dx <= 1; ++dx)
+            {
+                auto x2 = x + dx;
+                auto y2 = y + dy;
+                auto index = y2 * img.width + x2;
+
+                if(index >= 0 && index < img.width * img.height)
+                {
+                    auto v2 = ((glm::u8vec3 *)img.data + index)->r < 10; 
+                    if(val != v2)
+                    {
+                        found = true;
+                        break;
+                    }
+                }
+            }
+            
+            if(found)
+            {
+                break;
+            }
+        }
+        if(found)
+        {
+            pts.emplace_back(x, y);
+        }
+    }
+
+    kdtree tree(pts);
+
+    while (!WindowShouldClose())
     {
         BeginDrawing();
         ClearBackground(WHITE);
+        tree.draw();
         EndDrawing();
     }
-    
+
     CloseWindow();
 
     return 0;