diff --git a/client/src/main.c b/client/src/main.c
index b7bacf0..60709ce 100644
--- a/client/src/main.c
+++ b/client/src/main.c
@@ -34,8 +34,6 @@ typedef struct ClientContextStruct {
   UIContext* ui;
   HexContext* hex;
 
-  double  cursor[2];
-
   vec3    position;
 
   vec3    velocity;
@@ -97,6 +95,55 @@ uint32_t add_hex_region(ClientContext* context) {
   return i;
 }
 
+void hue_bar_cursor_callback(void* ptr, float x, float y) {
+  (void)x;
+
+  ClientContext* context = (ClientContext*)ptr;
+
+  if(context->ui->active_element == 0x02 && context->ui->active_container == 0x03) {
+    if(y < 0) y = 0;
+    if(y > 1) y = 1;
+
+    Container* container = context_container(0x03, context->ui);
+    container->layers[0].drawables_buffer[1].color[0][0] = y;
+    container->layers[0].drawables_buffer[1].color[1][0] = y;
+    container->layers[0].drawables_buffer[1].color[2][0] = y;
+    container->layers[0].drawables_buffer[1].color[3][0] = y;
+    add_transfers(
+        &container->layers[0].drawables_buffer[1].color[0],
+        container->layers[0].drawables,
+        1*sizeof(GPUDrawable) + offsetof(GPUDrawable, color),
+        4*sizeof(vec4),
+        context->render);
+  }
+}
+
+void hue_bar_button_callback(void* ptr, float x, float y, int button, int action, int mods) {
+  (void)mods;
+  (void)x;
+
+  ClientContext* context = (ClientContext*)ptr;
+  if(action == GLFW_PRESS && button == GLFW_MOUSE_BUTTON_LEFT) {
+    set_active_element(0x03, 0x02, context->ui);
+    if(y < 0) y = 0;
+    if(y > 1) y = 1;
+
+    Container* container = context_container(0x03, context->ui);
+    container->layers[0].drawables_buffer[1].color[0][0] = y;
+    container->layers[0].drawables_buffer[1].color[1][0] = y;
+    container->layers[0].drawables_buffer[1].color[2][0] = y;
+    container->layers[0].drawables_buffer[1].color[3][0] = y;
+    add_transfers(
+        &container->layers[0].drawables_buffer[1].color[0],
+        container->layers[0].drawables,
+        1*sizeof(GPUDrawable) + offsetof(GPUDrawable, color),
+        4*sizeof(vec4),
+        context->render);
+  } else if(action == GLFW_RELEASE && button == GLFW_MOUSE_BUTTON_LEFT) {
+    clear_active_element(context->ui);
+  }
+}
+
 VkResult color_ui(ClientContext* context) {
   GPUString strings[] = {
     {
@@ -221,6 +268,14 @@ VkResult color_ui(ClientContext* context) {
     .num_drawables = sizeof(drawables)/sizeof(GPUDrawable),
   };
 
+  UICallbacks callbacks[] = {
+    {
+      .element = 0x02,
+      .button = hue_bar_button_callback,
+      .cursor = hue_bar_cursor_callback,
+    },
+  };
+
   ContainerInput container = {
     .layers = &layer,
     .layer_count = 1,
@@ -228,6 +283,8 @@ VkResult color_ui(ClientContext* context) {
     .id = 0x03,
     .offset = {0, 0},
     .size = {190, 150},
+    .callbacks = callbacks,
+    .callback_count = sizeof(callbacks)/sizeof(UICallbacks),
   };
 
   return create_container(&container, context->render, context->ui);
@@ -687,7 +744,7 @@ void key_callback(GLFWwindow* window, int key, int scancode, int action, int mod
   (void)mods;
 
   ClientContext* context = (ClientContext*)glfwGetWindowUserPointer(window);
-  if(context->ui->active_captures & UI_EVENT_KEY) {
+  if(context->ui->active_callbacks != NULL && context->ui->active_callbacks->key != NULL) {
     // Pass key to active element
   } else {
     switch(key) {
@@ -923,7 +980,6 @@ void key_callback(GLFWwindow* window, int key, int scancode, int action, int mod
 }
 
 void button_callback(GLFWwindow* window, int button, int action, int mods) {
-  (void)mods;
   double cursor[2];
   uint32_t container;
   uint32_t element;
@@ -933,10 +989,35 @@ void button_callback(GLFWwindow* window, int button, int action, int mods) {
 
   glfwGetCursorPos(window, &cursor[0], &cursor[1]);
 
-  if(context->ui->active_captures & UI_EVENT_BUTTON) {
-    // Pass button to active element
+  if(context->ui->active_callbacks != NULL && context->ui->active_callbacks->button != NULL) { 
+    Container* container_ptr = context_container(context->ui->active_container, context->ui);
+    GPUDrawable* drawable_ptr = container_drawable(context->ui->active_element, container_ptr);
+    vec2 element_pos = {
+      drawable_ptr->pos[0] + container_ptr->data.offset[0],
+      drawable_ptr->pos[1] + container_ptr->data.offset[1],
+    };
+    anchor_offset(context->render, container_ptr, element_pos);
+    vec2 element_size = {
+      drawable_ptr->size[0],
+      drawable_ptr->size[1],
+    };
+    context->ui->active_callbacks->button(
+        context,
+        (cursor[0] - element_pos[0])/element_size[0],
+        (cursor[1] - element_pos[1])/element_size[1],
+        button,
+        action,
+        mods);
   } else if(ui_intersect(cursor, context->render, context->ui, &container, &element, position)) {
-    // Pass button to active UI element
+    Container* container_ptr = context_container(container, context->ui);
+    for(uint32_t c = 0; c < container_ptr->callback_count; c++) {
+      if(container_ptr->callbacks[c].element == element) {
+        if(container_ptr->callbacks[c].button != NULL) {
+          container_ptr->callbacks[c].button(context, position[0], position[1], button, action, mods);
+        }
+        break;
+      }
+    }
   } else {
     update_hex_click(cursor, context->hex, context->render);
     if(button == GLFW_MOUSE_BUTTON_MIDDLE) {
@@ -958,9 +1039,9 @@ void scroll_callback(GLFWwindow* window, double xoffset, double yoffset) {
   vec2 position;
 
   ClientContext* context = (ClientContext*)glfwGetWindowUserPointer(window);
-  if(context->ui->active_captures & UI_EVENT_SCROLL) {
+  if(context->ui->active_callbacks != NULL && context->ui->active_callbacks->scroll != NULL) {
     // Pass scroll to active element
-  } else if(ui_intersect(context->cursor, context->render, context->ui, &container, &element, position)) {
+  } else if(ui_intersect(context->ui->cursor, context->render, context->ui, &container, &element, position)) {
     // Pass scroll to hovered element
   } else {
     context->zoom = -yoffset;
@@ -973,23 +1054,45 @@ void cursor_callback(GLFWwindow* window, double xpos, double ypos) {
   uint32_t element;
   vec2 position;
   vec2 last_cursor = {
-    context->cursor[0],
-    context->cursor[1],
+    context->ui->cursor[0],
+    context->ui->cursor[1],
   };
 
-  context->cursor[0] = xpos;
-  context->cursor[1] = ypos;
+  context->ui->cursor[0] = xpos;
+  context->ui->cursor[1] = ypos;
 
   if(context->camera_mode == true) {
     context->cur_spin[0] = (xpos - last_cursor[0])/context->render->swapchain_extent.width*-100;
     context->cur_spin[1] = (ypos - last_cursor[1])/context->render->swapchain_extent.height*100;
   } else {
-    if(context->ui->active_captures & UI_EVENT_CURSOR) {
-      // Pass cursor to active element
-    } else if(ui_intersect(context->cursor, context->render, context->ui, &container, &element, position)) {
-      // Pass cursor to hovered element
+    if(context->ui->active_callbacks != NULL && context->ui->active_callbacks->cursor != NULL) {
+      Container* container_ptr = context_container(context->ui->active_container, context->ui);
+      GPUDrawable* drawable_ptr = container_drawable(context->ui->active_element, container_ptr);
+      vec2 element_pos = {
+        drawable_ptr->pos[0] + container_ptr->data.offset[0],
+        drawable_ptr->pos[1] + container_ptr->data.offset[1],
+      };
+      anchor_offset(context->render, container_ptr, element_pos);
+      vec2 element_size = {
+        drawable_ptr->size[0],
+        drawable_ptr->size[1],
+      };
+      context->ui->active_callbacks->cursor(
+          context,
+          (context->ui->cursor[0] - element_pos[0])/element_size[0],
+          (context->ui->cursor[1] - element_pos[1])/element_size[1]);
+    } else if(ui_intersect(context->ui->cursor, context->render, context->ui, &container, &element, position)) {
+      Container* container_ptr = context_container(container, context->ui);
+      for(uint32_t c = 0; c < container_ptr->callback_count; c++) {
+        if(container_ptr->callbacks[c].element == element) {
+          if(container_ptr->callbacks[c].button != NULL) {
+            container_ptr->callbacks[c].cursor(context, position[0], position[1]);
+          }
+          break;
+        }
+      }
     } else {
-      update_hex_hover(context->cursor, context->hex, context->render);
+      update_hex_hover(context->ui->cursor, context->hex, context->render);
     }
   }
 }
diff --git a/client/src/ui.c b/client/src/ui.c
index 4639d35..e8cd953 100644
--- a/client/src/ui.c
+++ b/client/src/ui.c
@@ -263,7 +263,12 @@ VkResult create_container(
   }
 
   context->containers[index].layer_count = container->layer_count;
-
+  context->containers[index].callbacks = malloc(sizeof(UICallbacks)*container->callback_count);
+  context->containers[index].callback_count = container->callback_count;
+  memcpy(
+      context->containers[index].callbacks,
+      container->callbacks,
+      sizeof(UICallbacks)*container->callback_count);
   return VK_SUCCESS;
 }
 
@@ -1148,6 +1153,35 @@ VkResult map_string(
   return VK_SUCCESS;
 }
 
+Container* context_container(uint32_t container_id, UIContext* ui) {
+  uint32_t c;
+  Container* ret = NULL;
+  for(c = 0; c < ui->max_containers; c++) {
+    if(ui->containers[c].id == container_id) {
+      ret = &ui->containers[c];
+      break;
+    }
+  }
+
+  return ret;
+}
+
+GPUDrawable* container_drawable(uint32_t element_id, Container* container) {
+  if(container == NULL || element_id == 0) {
+    return NULL;
+  }
+
+  for(uint32_t l = 0; l < container->layer_count; l++) {
+    for(uint32_t d = 0; d < container->layers[l].data.num_drawables; d++) {
+      if(container->layers[l].drawables_buffer[d].id == element_id) {
+        return &container->layers[l].drawables_buffer[d];
+      }
+    }
+  }
+
+  return NULL;
+}
+
 VkResult update_ui_string(
     char* string,
     uint32_t container_id,
@@ -1157,18 +1191,12 @@ VkResult update_ui_string(
     RenderContext* gpu) {
   VkResult result;
 
-  uint32_t c;
-  for(c = 0; c < ui->max_containers; c++) {
-    if(ui->containers[c].id == container_id) {
-      break;
-    }
-  }
 
-  if(c == ui->max_containers) {
+  Container* container = context_container(container_id, ui);
+  if(container == NULL) {
     return VK_ERROR_UNKNOWN;
   }
 
-  Container* container = &ui->containers[c];
   Layer* layer = &container->layers[layer_index];
   layer->strings_buffer[string_index].length = strlen(string);
   if(strlen(string) > 0) {
@@ -1223,30 +1251,13 @@ bool ui_intersect(
     uint32_t* container,
     uint32_t* element,
     vec2 position) { 
-  vec2 screen = {
-    gpu->swapchain_extent.width/gpu->window_scale[0],
-    gpu->swapchain_extent.height/gpu->window_scale[1],
-  };
   for(uint32_t c = 0; c < ui->max_containers; c++) {
     if(ui->containers[c].id == 0x00000000) {
       continue;
     }
 
     vec2 container_offset = {ui->containers[c].data.offset[0], ui->containers[c].data.offset[1]};
-    switch(ui->containers[c].data.anchor) {
-    case ANCHOR_TOP_LEFT:
-      break;
-    case ANCHOR_TOP_RIGHT:
-      container_offset[0] += screen[0] - ui->containers[c].data.size[0];
-      break;
-    case ANCHOR_BOTTOM_LEFT:
-      container_offset[1] += screen[1] - ui->containers[c].data.size[1];
-      break;
-    case ANCHOR_BOTTOM_RIGHT:
-      container_offset[0] += screen[0] - ui->containers[c].data.size[0];
-      container_offset[1] += screen[1] - ui->containers[c].data.size[1];
-      break;
-    }
+    anchor_offset(gpu, &ui->containers[c], container_offset);
 
     for(uint32_t l = 0; l < ui->containers[c].layer_count; l++) {
       for(uint32_t d = 0; d < ui->containers[c].layers[l].data.num_drawables; d++) {
@@ -1270,3 +1281,48 @@ bool ui_intersect(
   return false;
 }
 
+void clear_active_element(UIContext* ui) {
+  ui->active_callbacks = NULL;
+  ui->active_element = 0;
+  ui->active_container = 0;
+}
+
+void set_active_element(uint32_t container, uint32_t element, UIContext* ui) {
+  ui->active_container = container;
+  ui->active_element = element;
+  ui->active_callbacks = NULL;
+  Container* container_ptr = context_container(container, ui);
+  if(container_ptr == NULL) {
+    fprintf(stderr, "set_active_element passed invalid container id");
+    return;
+  }
+  
+  for(uint32_t c = 0; c < container_ptr->callback_count; container_ptr++) {
+    if(container_ptr->callbacks[c].element == element) {
+      ui->active_callbacks = &container_ptr->callbacks[c];
+      break;
+    }
+  }
+}
+
+void anchor_offset(RenderContext* gpu, Container* container, vec2 offset) {
+  vec2 screen = {
+    gpu->swapchain_extent.width/gpu->window_scale[0],
+    gpu->swapchain_extent.height/gpu->window_scale[1],
+  };
+
+  switch(container->data.anchor) {
+  case ANCHOR_TOP_LEFT:
+    break;
+  case ANCHOR_TOP_RIGHT:
+    offset[0] += screen[0] - container->data.size[0];
+    break;
+  case ANCHOR_BOTTOM_LEFT:
+    offset[1] += screen[1] - container->data.size[1];
+    break;
+  case ANCHOR_BOTTOM_RIGHT:
+    offset[0] += screen[0] - container->data.size[0];
+    offset[1] += screen[1] - container->data.size[1];
+    break;
+  }
+}