diff --git a/doc/en/scripting/builtins/libassets.md b/doc/en/scripting/builtins/libassets.md
index bd095435..b39239a5 100644
--- a/doc/en/scripting/builtins/libassets.md
+++ b/doc/en/scripting/builtins/libassets.md
@@ -25,4 +25,12 @@ assets.parse_model(
     -- Model name after loading
     name: str
 )
+
+-- Creates a Canvas from a loaded texture.
+assets.to_canvas(
+    -- The name of the loaded texture.
+    -- Both standalone textures ("texture_name") and
+    -- those in an atlas ("atlas:texture_name") are supported
+    name: str
+) --> Canvas
 ```
diff --git a/doc/ru/scripting/builtins/libassets.md b/doc/ru/scripting/builtins/libassets.md
index 2c510948..ec069e1a 100644
--- a/doc/ru/scripting/builtins/libassets.md
+++ b/doc/ru/scripting/builtins/libassets.md
@@ -25,4 +25,12 @@ assets.parse_model(
     -- Имя модели после загрузки
     name: str
 )
+
+-- Создаёт холст (Canvas) из загруженной текстуры
+assets.to_canvas(
+    -- Имя загруженной текстуры. 
+    -- Поддерживается как отдельные ("имя_текстуры"), 
+    -- так и находящиеся в атласе ("атлас:имя_текстуры").
+    name: str
+) --> Canvas
 ```
diff --git a/res/scripts/stdlib.lua b/res/scripts/stdlib.lua
index 6e1280cd..a81c1232 100644
--- a/res/scripts/stdlib.lua
+++ b/res/scripts/stdlib.lua
@@ -298,7 +298,9 @@ function __vc_on_hud_open()
     end)
     input.add_callback("key:escape", function()
         if menu.page ~= "" then
-            menu:reset()
+            if not menu:back() then
+                menu:reset()
+            end
         elseif hud.is_inventory_open() then
             hud.close_inventory()
         else
diff --git a/src/assets/assetload_funcs.cpp b/src/assets/assetload_funcs.cpp
index d865cc1a..4fda3b0d 100644
--- a/src/assets/assetload_funcs.cpp
+++ b/src/assets/assetload_funcs.cpp
@@ -184,7 +184,7 @@ assetload::postfunc assetload::atlas(
         if (!append_atlas(builder, file)) continue;
     }
     std::set<std::string> names = builder.getNames();
-    Atlas* atlas = builder.build(2, false).release();
+    Atlas* atlas = builder.build(ATLAS_EXTRUSION, false).release();
     return [=](auto assets) {
         atlas->prepare();
         assets->store(std::unique_ptr<Atlas>(atlas), name);
@@ -501,7 +501,7 @@ static bool load_animation(
             }
             if (!append_atlas(builder, file)) continue;
         }
-        auto srcAtlas = builder.build(2, true);
+        auto srcAtlas = builder.build(ATLAS_EXTRUSION, true);
         if (frameList.empty()) {
             for (const auto& frameName : builder.getNames()) {
                 frameList.emplace_back(frameName, 0);
diff --git a/src/constants.hpp b/src/constants.hpp
index 6544316e..91e2c180 100644
--- a/src/constants.hpp
+++ b/src/constants.hpp
@@ -61,6 +61,8 @@ inline constexpr int ITEM_ICON_SIZE = 48;
 
 inline constexpr int TRANSLUCENT_BLOCKS_SORT_INTERVAL = 8;
 
+inline constexpr int ATLAS_EXTRUSION = 2;
+
 inline const std::string SHADERS_FOLDER = "shaders";
 inline const std::string TEXTURES_FOLDER = "textures";
 inline const std::string FONTS_FOLDER = "fonts";
diff --git a/src/engine/Engine.cpp b/src/engine/Engine.cpp
index a977f354..3053b613 100644
--- a/src/engine/Engine.cpp
+++ b/src/engine/Engine.cpp
@@ -26,6 +26,7 @@
 #include "graphics/core/ImageData.hpp"
 #include "graphics/core/Shader.hpp"
 #include "graphics/ui/GUI.hpp"
+#include "graphics/ui/elements/Menu.hpp"
 #include "objects/rigging.hpp"
 #include "logic/EngineController.hpp"
 #include "logic/CommandsInterpreter.hpp"
@@ -154,6 +155,14 @@ void Engine::initializeClient() {
         },
         true
     ));
+
+    keepAlive(this->input->addKeyCallback(Keycode::ESCAPE, [this]() {
+        auto& menu = *gui->getMenu();
+        if (menu.hasOpenPage() && menu.back()) {
+            return true;
+        }
+        return false;
+    }));
 }
 
 void Engine::initialize(CoreParameters coreParameters) {
diff --git a/src/frontend/debug_panel.cpp b/src/frontend/debug_panel.cpp
index 10c6b85c..c42b2930 100644
--- a/src/frontend/debug_panel.cpp
+++ b/src/frontend/debug_panel.cpp
@@ -9,6 +9,7 @@
 #include "graphics/ui/elements/TextBox.hpp"
 #include "graphics/ui/elements/TrackBar.hpp"
 #include "graphics/ui/elements/InputBindBox.hpp"
+#include "graphics/ui/GUI.hpp"
 #include "graphics/render/WorldRenderer.hpp"
 #include "graphics/render/ParticlesRenderer.hpp"
 #include "graphics/render/ChunksRenderer.hpp"
@@ -43,10 +44,15 @@ static std::shared_ptr<Label> create_label(GUI& gui, wstringsupplier supplier) {
     return label;
 }
 
+static bool should_keep_previous(GUI& gui) {
+    return !gui.getInput().isCursorLocked();
+}
+
 // TODO: move to xml
 // TODO: move to xml finally
 // TODO: move to xml finally
 // TODO: move to xml finally
+// TODO: move to xml finally
 std::shared_ptr<UINode> create_debug_panel(
     Engine& engine, 
     Level& level, 
@@ -81,7 +87,7 @@ std::shared_ptr<UINode> create_debug_panel(
         fpsMax = fps;
     });
 
-    panel->listenInterval(1.0f, [&engine]() {
+    panel->listenInterval(1.0f, [&engine, &gui]() {
         const auto& network = engine.getNetwork();
         size_t totalDownload = network.getTotalDownload();
         size_t totalUpload = network.getTotalUpload();
@@ -135,7 +141,16 @@ std::shared_ptr<UINode> create_debug_panel(
                std::to_wstring(player.getId());
     }));
     panel->add(create_label(gui, [&]() -> std::wstring {
-        const auto& vox = player.selection.vox;
+        // TODO: move to xml finally
+        static voxel prevVox = {BLOCK_VOID, {}};
+
+        auto vox = player.selection.vox;
+        if (vox.id == BLOCK_VOID && should_keep_previous(gui)) {
+            vox = prevVox;
+        } else {
+            prevVox = vox;
+        }
+
         std::wstringstream stream;
         stream << "r:" << vox.state.rotation << " s:"
                 << std::bitset<3>(vox.state.segment) << " u:"
@@ -148,8 +163,17 @@ std::shared_ptr<UINode> create_debug_panel(
         }
     }));
     panel->add(create_label(gui, [&]() -> std::wstring {
-        const auto& selection = player.selection;
+        // TODO: move to xml finally
+        static CursorSelection prevSelection {};
+
+        auto selection = player.selection;
         const auto& vox = selection.vox;
+        if (vox.id == BLOCK_VOID && should_keep_previous(gui)) {
+            selection = prevSelection;
+        } else {
+            prevSelection = selection;
+        }
+
         if (vox.id == BLOCK_VOID) {
             return L"x: - y: - z: -";
         }
@@ -158,7 +182,16 @@ std::shared_ptr<UINode> create_debug_panel(
                L" z: " + std::to_wstring(selection.actualPosition.z);
     }));
     panel->add(create_label(gui, [&]() {
+        // TODO: move to xml finally
+        static entityid_t prevEid = ENTITY_NONE;
+
         auto eid = player.getSelectedEntity();
+        if (eid == ENTITY_NONE && should_keep_previous(gui)) {
+            eid = prevEid;
+        } else {
+            prevEid = eid;
+        }
+
         if (eid == ENTITY_NONE) {
             return std::wstring {L"entity: -"};
         } else if (auto entity = level.entities->get(eid)) {
diff --git a/src/graphics/core/Atlas.cpp b/src/graphics/core/Atlas.cpp
index be205d1e..d06a20b9 100644
--- a/src/graphics/core/Atlas.cpp
+++ b/src/graphics/core/Atlas.cpp
@@ -49,6 +49,14 @@ ImageData* Atlas::getImage() const {
     return image.get();
 }
 
+std::shared_ptr<Texture> Atlas::shareTexture() const {
+    return texture;
+}
+
+std::shared_ptr<ImageData> Atlas::shareImageData() const {
+    return image;
+}
+
 void AtlasBuilder::add(const std::string& name, std::unique_ptr<ImageData> image) {
     entries.push_back(atlasentry{name, std::shared_ptr<ImageData>(image.release())});
     names.insert(name);
diff --git a/src/graphics/core/Atlas.hpp b/src/graphics/core/Atlas.hpp
index af3e4721..adea16a4 100644
--- a/src/graphics/core/Atlas.hpp
+++ b/src/graphics/core/Atlas.hpp
@@ -14,8 +14,8 @@ class ImageData;
 class Texture;
 
 class Atlas {
-    std::unique_ptr<Texture> texture;
-    std::unique_ptr<ImageData> image;
+    std::shared_ptr<Texture> texture;
+    std::shared_ptr<ImageData> image;
     std::unordered_map<std::string, UVRegion> regions;
 public:
     /// @param image atlas raster
@@ -36,6 +36,9 @@ public:
 
     Texture* getTexture() const;
     ImageData* getImage() const;
+
+    std::shared_ptr<Texture> shareTexture() const;
+    std::shared_ptr<ImageData> shareImageData() const;
 };
 
 struct atlasentry {
diff --git a/src/graphics/core/ImageData.cpp b/src/graphics/core/ImageData.cpp
index 44a1936e..3a5e3cb6 100644
--- a/src/graphics/core/ImageData.cpp
+++ b/src/graphics/core/ImageData.cpp
@@ -95,6 +95,17 @@ void ImageData::blit(const ImageData& image, int x, int y) {
     throw std::runtime_error("mismatching format");
 }
 
+std::unique_ptr<ImageData> ImageData::cropped(int x, int y, int width, int height) const {
+    width = std::min<int>(width, this->width - x);
+    height = std::min<int>(height, this->height - y);
+    if (width <= 0 || height <= 0) {
+        throw std::runtime_error("invalid crop dimensions");
+    }
+    auto subImage = std::make_unique<ImageData>(format, width, height);
+    subImage->blitMatchingFormat(*this, -x, -y);
+    return subImage;
+}
+
 static bool clip_line(int& x1, int& y1, int& x2, int& y2, int width, int height) {
     const int left = 0;
     const int right = width;
diff --git a/src/graphics/core/ImageData.hpp b/src/graphics/core/ImageData.hpp
index d09a0411..86396568 100644
--- a/src/graphics/core/ImageData.hpp
+++ b/src/graphics/core/ImageData.hpp
@@ -33,6 +33,8 @@ public:
     void extrude(int x, int y, int w, int h);
     void fixAlphaColor();
 
+    std::unique_ptr<ImageData> cropped(int x, int y, int width, int height) const;
+
     ubyte* getData() const {
         return data.get();
     }
diff --git a/src/graphics/core/Texture.cpp b/src/graphics/core/Texture.cpp
index 1dc18a65..04285aa8 100644
--- a/src/graphics/core/Texture.cpp
+++ b/src/graphics/core/Texture.cpp
@@ -51,6 +51,14 @@ void Texture::reload(const ubyte* data) {
     glBindTexture(GL_TEXTURE_2D, id);
     glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, width, height, 0,
         GL_RGBA, GL_UNSIGNED_BYTE, static_cast<const GLvoid*>(data));
+    glGenerateMipmap(GL_TEXTURE_2D);
+    glBindTexture(GL_TEXTURE_2D, 0);
+}
+
+void Texture::reloadPartial(const ImageData& image, uint x, uint y, uint w, uint h) {
+    glBindTexture(GL_TEXTURE_2D, id);
+    glTexSubImage2D(GL_TEXTURE_2D, 0, x, y, w, h, GL_RGBA, GL_UNSIGNED_BYTE, image.getData());
+    glGenerateMipmap(GL_TEXTURE_2D);
     glBindTexture(GL_TEXTURE_2D, 0);
 }
 
diff --git a/src/graphics/core/Texture.hpp b/src/graphics/core/Texture.hpp
index 59568619..5e67890c 100644
--- a/src/graphics/core/Texture.hpp
+++ b/src/graphics/core/Texture.hpp
@@ -19,6 +19,7 @@ public:
     virtual void bind() const;
     virtual void unbind() const;
     void reload(const ubyte* data);
+    void reloadPartial(const ImageData& image, uint x, uint y, uint w, uint h);
 
     void setNearestFilter();
 
diff --git a/src/graphics/render/BlocksPreview.cpp b/src/graphics/render/BlocksPreview.cpp
index 4b8bfee9..ad025d3c 100644
--- a/src/graphics/render/BlocksPreview.cpp
+++ b/src/graphics/render/BlocksPreview.cpp
@@ -137,5 +137,5 @@ std::unique_ptr<Atlas> BlocksPreview::build(
         builder.add(def.name, draw(cache, shader, fbo, batch, def, iconSize));
     }
     fbo.unbind();
-    return builder.build(2);
+    return builder.build(ATLAS_EXTRUSION);
 }
diff --git a/src/logic/scripting/lua/libs/libassets.cpp b/src/logic/scripting/lua/libs/libassets.cpp
index 9924069a..35720195 100644
--- a/src/logic/scripting/lua/libs/libassets.cpp
+++ b/src/logic/scripting/lua/libs/libassets.cpp
@@ -7,7 +7,9 @@
 #include "engine/Engine.hpp"
 #include "graphics/commons/Model.hpp"
 #include "graphics/core/Texture.hpp"
+#include "graphics/core/Atlas.hpp"
 #include "util/Buffer.hpp"
+#include "../usertypes/lua_type_canvas.hpp"
 
 using namespace scripting;
 
@@ -64,8 +66,47 @@ static int l_parse_model(lua::State* L) {
     return 0;
 }
 
+static int l_to_canvas(lua::State* L) {
+    auto& assets = *engine->getAssets();
+
+    auto alias = lua::require_lstring(L, 1);
+    size_t sep = alias.rfind(':');
+    if (sep == std::string::npos) {
+        auto texture = assets.getShared<Texture>(std::string(alias));
+        if (texture != nullptr) {
+            auto image = texture->readData();
+            return lua::newuserdata<lua::LuaCanvas>(
+                L, texture, std::move(image)
+            );
+        }
+        return 0;
+    }
+    auto atlasName = alias.substr(0, sep);
+    
+    if (auto atlas = assets.get<Atlas>(std::string(atlasName))) {
+        auto textureName = std::string(alias.substr(sep + 1));
+        auto image = atlas->shareImageData();
+        auto texture = atlas->shareTexture();
+
+        if (auto region = atlas->getIf(textureName)) {
+            UVRegion uvRegion = *region;
+            int atlasWidth = static_cast<int>(image->getWidth());
+            int atlasHeight = static_cast<int>(image->getHeight());
+            int x = static_cast<int>(uvRegion.u1 * atlasWidth);
+            int y = static_cast<int>(uvRegion.v1 * atlasHeight);
+            int w = static_cast<int>(uvRegion.getWidth() * atlasWidth);
+            int h = static_cast<int>(uvRegion.getHeight() * atlasHeight);
+            return lua::newuserdata<lua::LuaCanvas>(
+                L, std::move(texture), image->cropped(x, y, w, h), uvRegion
+            );
+        }
+    }
+    return 0;
+}
+
 const luaL_Reg assetslib[] = {
     {"load_texture", lua::wrap<l_load_texture>},
     {"parse_model", lua::wrap<l_parse_model>},
+    {"to_canvas", lua::wrap<l_to_canvas>},
     {nullptr, nullptr}
 };
diff --git a/src/logic/scripting/lua/libs/libgui.cpp b/src/logic/scripting/lua/libs/libgui.cpp
index 588ab01b..3697d39c 100644
--- a/src/logic/scripting/lua/libs/libgui.cpp
+++ b/src/logic/scripting/lua/libs/libgui.cpp
@@ -58,7 +58,7 @@ DocumentNode get_document_node(lua::State* L, int idx) {
 static int l_menu_back(lua::State* L) {
     auto node = get_document_node(L);
     if (auto menu = dynamic_cast<Menu*>(node.node.get())) {
-        menu->back();
+        return lua::pushboolean(L, menu->back());
     }
     return 0;
 }
diff --git a/src/logic/scripting/lua/usertypes/lua_type_canvas.cpp b/src/logic/scripting/lua/usertypes/lua_type_canvas.cpp
index 3343fe71..325f916f 100644
--- a/src/logic/scripting/lua/usertypes/lua_type_canvas.cpp
+++ b/src/logic/scripting/lua/usertypes/lua_type_canvas.cpp
@@ -11,14 +11,59 @@
 using namespace lua;
 
 LuaCanvas::LuaCanvas(
-    std::shared_ptr<Texture> inTexture, std::shared_ptr<ImageData> inData
+    std::shared_ptr<Texture> texture,
+    std::shared_ptr<ImageData> data,
+    UVRegion region
 )
-    : mTexture(std::move(inTexture)), mData(std::move(inData)) {
+    : texture(std::move(texture)),
+      data(std::move(data)),
+      region(std::move(region)) {
+}
+
+void LuaCanvas::update(int extrusion) {
+    if (!hasTexture()) {
+        return;
+    }
+    if (region.isFull()) {
+        texture->reload(*data);
+    } else {
+        uint texWidth = texture->getWidth();
+        uint texHeight = texture->getHeight();
+        uint imgWidth = data->getWidth();
+        uint imgHeight = data->getHeight();
+
+        uint x = static_cast<uint>(region.u1 * texWidth);
+        uint y = static_cast<uint>(region.v1 * texHeight);
+        uint w = static_cast<uint>((region.u2 - region.u1) * texWidth);
+        uint h = static_cast<uint>((region.v2 - region.v1) * texHeight);
+
+        w = std::min<uint>(w, imgWidth);
+        h = std::min<uint>(h, imgHeight);
+
+        if (extrusion > 0) {
+            auto extruded = std::make_unique<ImageData>(
+                data->getFormat(),
+                w + extrusion * 2,
+                h + extrusion * 2
+            );
+            extruded->blit(*data, extrusion, extrusion);
+            extruded->extrude(0, 0, w + extrusion * 2, h + extrusion * 2);
+            texture->reloadPartial(
+                *extruded,
+                x - extrusion,
+                y - extrusion,
+                w + extrusion * 2,
+                h + extrusion * 2
+            );
+        } else {
+            texture->reloadPartial(*data, x, y, w, h);
+        }
+    }
 }
 
 void LuaCanvas::createTexture() {
-    mTexture = Texture::from(mData.get());
-    mTexture->setMipMapping(false, true);
+    texture = Texture::from(data.get());
+    texture->setMipMapping(false, true);
 }
 
 union RGBA {
@@ -42,7 +87,7 @@ static RGBA* get_at(const ImageData& data, uint x, uint y) {
 
 static RGBA* get_at(State* L, uint x, uint y) {
     if (auto canvas = touserdata<LuaCanvas>(L, 1)) {
-        return get_at(canvas->data(), x, y);
+        return get_at(canvas->getData(), x, y);
     }
     return nullptr;
 }
@@ -98,7 +143,7 @@ static LuaCanvas& require_canvas(State* L, int idx) {
 
 static int l_clear(State* L) {
     auto& canvas = require_canvas(L, 1);
-    auto& image = canvas.data();
+    auto& image = canvas.getData();
     ubyte* data = image.getData();
     RGBA rgba {};
     if (gettop(L) == 1) {
@@ -123,7 +168,7 @@ static int l_line(State* L) {
 
     RGBA rgba = get_rgba(L, 6);
     if (auto canvas = touserdata<LuaCanvas>(L, 1)) {
-        auto& image = canvas->data();
+        auto& image = canvas->getData();
         image.drawLine(
             x1, y1, x2, y2, glm::ivec4 {rgba.r, rgba.g, rgba.b, rgba.a}
         );
@@ -136,13 +181,13 @@ static int l_blit(State* L) {
     auto& src = require_canvas(L, 2);
     int dst_x = tointeger(L, 3);
     int dst_y = tointeger(L, 4);
-    dst.data().blit(src.data(), dst_x, dst_y);
+    dst.getData().blit(src.getData(), dst_x, dst_y);
     return 0;
 }
 
 static int l_set_data(State* L) {
     auto& canvas = require_canvas(L, 1);
-    auto& image = canvas.data();
+    auto& image = canvas.getData();
     auto data = image.getData();
 
     if (lua::isstring(L, 2)) {
@@ -167,9 +212,7 @@ static int l_set_data(State* L) {
 
 static int l_update(State* L) {
     if (auto canvas = touserdata<LuaCanvas>(L, 1)) {
-        if (canvas->hasTexture()) {
-            canvas->texture().reload(canvas->data());
-        }
+        canvas->update();
     }
     return 0;
 }
@@ -203,7 +246,7 @@ static int l_meta_index(State* L) {
     if (texture == nullptr) {
         return 0;
     }
-    auto& data = texture->data();
+    auto& data = texture->getData();
     if (isnumber(L, 2)) {
         if (auto pixel = get_at(data, static_cast<uint>(tointeger(L, 2)))) {
             return pushinteger(L, pixel->rgba);
@@ -232,7 +275,7 @@ static int l_meta_newindex(State* L) {
     if (texture == nullptr) {
         return 0;
     }
-    auto& data = texture->data();
+    auto& data = texture->getData();
     if (isnumber(L, 2) && isnumber(L, 3)) {
         if (auto pixel = get_at(data, static_cast<uint>(tointeger(L, 2)))) {
             pixel->rgba = static_cast<uint>(tointeger(L, 3));
diff --git a/src/logic/scripting/lua/usertypes/lua_type_canvas.hpp b/src/logic/scripting/lua/usertypes/lua_type_canvas.hpp
index 43fbbd10..198313cb 100644
--- a/src/logic/scripting/lua/usertypes/lua_type_canvas.hpp
+++ b/src/logic/scripting/lua/usertypes/lua_type_canvas.hpp
@@ -1,6 +1,8 @@
 #pragma once
 
 #include "../lua_commons.hpp"
+#include "maths/UVRegion.hpp"
+#include "constants.hpp"
 
 class Texture;
 class ImageData;
@@ -9,8 +11,9 @@ namespace lua {
     class LuaCanvas : public Userdata {
     public:
         explicit LuaCanvas(
-            std::shared_ptr<Texture> inTexture,
-            std::shared_ptr<ImageData> inData
+            std::shared_ptr<Texture> texture,
+            std::shared_ptr<ImageData> data,
+            UVRegion region = UVRegion(0, 0, 1, 1)
         );
         ~LuaCanvas() override = default;
 
@@ -18,29 +21,32 @@ namespace lua {
             return TYPENAME;
         }
 
-        [[nodiscard]] auto& texture() const {
-            return *mTexture;
+        [[nodiscard]] auto& getTexture() const {
+            return *texture;
         }
 
-        [[nodiscard]] auto& data() const {
-            return *mData;
+        [[nodiscard]] auto& getData() const {
+            return *data;
         }
 
         [[nodiscard]] bool hasTexture() const {
-            return mTexture != nullptr;
+            return texture != nullptr;
         }
 
         auto shareTexture() const {
-            return mTexture;
+            return texture;
         }
 
+        void update(int extrusion = ATLAS_EXTRUSION);
+
         void createTexture();
 
         static int createMetatable(lua::State*);
         inline static std::string TYPENAME = "Canvas";
     private:
-        std::shared_ptr<Texture> mTexture; // nullable
-        std::shared_ptr<ImageData> mData;
+        std::shared_ptr<Texture> texture; // nullable
+        std::shared_ptr<ImageData> data;
+        UVRegion region;
     };
     static_assert(!std::is_abstract<LuaCanvas>());
 }
diff --git a/src/maths/UVRegion.hpp b/src/maths/UVRegion.hpp
index 354c939b..f7e398d8 100644
--- a/src/maths/UVRegion.hpp
+++ b/src/maths/UVRegion.hpp
@@ -1,8 +1,7 @@
 #pragma once
 
 #include <cmath>
-#include <glm/vec2.hpp>
-#include <glm/vec4.hpp>
+#include <glm/glm.hpp>
 
 struct UVRegion {
     float u1;
@@ -69,4 +68,10 @@ struct UVRegion {
         copy.scale(scale);
         return copy;
     }
+
+    bool isFull() const {
+        const auto e = 1e-7;
+        return glm::abs(u1 - 0.0) < e && glm::abs(v1 - 0.0) < e &&
+               glm::abs(u2 - 1.0) < e && glm::abs(v2 - 1.0) < e;
+    }
 };