diff --git a/examples/text_editor/basic.lc b/examples/text_editor/basic.lc
new file mode 100644
index 0000000..6059bfe
--- /dev/null
+++ b/examples/text_editor/basic.lc
@@ -0,0 +1,34 @@
+ClampInt :: proc(val: int, min: int, max: int): int {
+    result := val;
+    if (val < min) result = min;
+    if (val > max) result = max;
+    return result;
+}
+
+MinInt :: proc(a: int, b: int): int {
+    result := a;
+    if (a > b) result = b;
+    return result;
+}
+
+MaxInt :: proc(a: int, b: int): int {
+    result := b;
+    if (a > b) result = a;
+    return result;
+}
+
+MaxFloat :: proc(a: float, b: float): float {
+    if a > b return a;
+    return b;
+}
+
+MinFloat :: proc(a: float, b: float): float {
+    if a > b return b;
+    return a;
+}
+
+ClampFloat :: proc(val: float, min: float, max: float): float {
+    if (val > max) return max;
+    if (val < min) return min;
+    return val;
+}
diff --git a/examples/text_editor/buffer.lc b/examples/text_editor/buffer.lc
index f703ea6..c84dd13 100644
--- a/examples/text_editor/buffer.lc
+++ b/examples/text_editor/buffer.lc
@@ -27,25 +27,6 @@ GetRangeSize :: proc(range: Range): int {
     return result;
 }
 
-ClampInt :: proc(val: int, min: int, max: int): int {
-    result := val;
-    if (val < min) result = min;
-    if (val > max) result = max;
-    return result;
-}
-
-MinInt :: proc(a: int, b: int): int {
-    result := a;
-    if (a > b) result = b;
-    return result;
-}
-
-MaxInt :: proc(a: int, b: int): int {
-    result := b;
-    if (a > b) result = a;
-    return result;
-}
-
 AdjustUTF8PosUnsafe :: proc(buffer: *Buffer, pos: int, direction: int = 1): int {
     for pos >= 0 && pos < buffer.len && IsUTF8ContinuationByte(buffer.data[pos]) {
         pos += direction;
diff --git a/examples/text_editor/main.lc b/examples/text_editor/main.lc
index ef0e908..738e528 100644
--- a/examples/text_editor/main.lc
+++ b/examples/text_editor/main.lc
@@ -6,448 +6,16 @@
 - Ctrl+V
 - Ctrl+X
 - Open a document dialog, save document to disk
+- Buffer bound  undo,redo
 */
 import "raylib";
 import "std_types";
 import "libc";
 
-Selection :: struct {
-    a: int;
-    b: int;
-}
-
-GetRange :: proc(s: Selection): Range {
-    result: Range = {MinInt(s.a, s.b), MaxInt(s.a, s.b)};
-    return result;
-}
-
-Window :: struct {
-    buffer: *Buffer;
-    cursor: Selection;
-    scroll: Vector2;
-    mouse_scrolling: bool;
-
-    rect: Rect2P;
-}
-
-FocusedWindow: *Window;
-WindowStack: [8]Window;
-WindowStackCount: int;
-
-AddWindow :: proc(window: Window) {
-    if (WindowStackCount + 1 >= 8) return;
-
-    WindowStack[WindowStackCount] = window;
-    WindowStackCount += 1;
-}
-
-ComputeWindowRects :: proc(screen_rect: Rect2P) {
-    WindowStack[0].rect = CutLeft(&screen_rect, 0.5 * GetRectX(screen_rect));
-    WindowStack[1].rect = CutLeft(&screen_rect, 1.0 * GetRectX(screen_rect));
-}
-
-UpdateAndDrawWindows :: proc(font: Font, font_size: float) {
-    for i := 0; i < WindowStackCount; i += 1 {
-        window: *Window = &WindowStack[i];
-        UpdateAndDrawWindow(window, font, font_size);
-    }
-}
-
-UpdateAndDrawWindow :: proc(w: *Window, font: Font, font_size: float) {
-    initial_cursor: Selection = w.cursor;
-    text_window_rect := w.rect;
-    bar := CutRight(&text_window_rect, 10);
-    line_numbers_rect := CutLeft(&text_window_rect, Monosize.x * 4);
-    line_numbers_rect; @unused
-
-    buffer_end_vpos := CalculateVisualPos(w.buffer, w.buffer.len - 1);
-    buffer_end_wpos := CalculateWorldPosUnscrolled(buffer_end_vpos);
-
-    if CheckCollisionPointRec(GetMousePosition(), Rect2PToRectangle(w.rect)) {
-        if w != FocusedWindow {
-            SetMouseCursor(MOUSE_CURSOR_POINTING_HAND);
-        }
-        if IsMouseButtonPressed(MOUSE_BUTTON_LEFT) {
-            FocusedWindow = w;
-        }
-    }
-
-
-    if w == FocusedWindow {
-        if IsKeyPressed(KEY_LEFT) || IsKeyPressedRepeat(KEY_LEFT) {
-            if IsKeyDown(KEY_LEFT_SHIFT) {
-                if IsKeyDown(KEY_LEFT_CONTROL) {
-                    w.cursor.b = SeekOnWordBoundary(w.buffer, w.cursor.b, GO_BACKWARD);
-                } else {
-                    w.cursor.b = MoveLeft(w.buffer, w.cursor.b);
-                }
-            } else {
-                if IsKeyDown(KEY_LEFT_CONTROL) {
-                    w.cursor.a = SeekOnWordBoundary(w.buffer, w.cursor.a, GO_BACKWARD);
-                    w.cursor.b = w.cursor.a;
-                } else {
-                    range := GetRange(w.cursor);
-                    if GetRangeSize(range) > 0 {
-                        w.cursor.a = MinInt(w.cursor.a, w.cursor.b);
-                        w.cursor.b = MinInt(w.cursor.a, w.cursor.b);
-                    } else {
-                        w.cursor.a = MoveLeft(w.buffer, w.cursor.a);
-                        w.cursor.b = w.cursor.a;
-                    }
-                }
-            }
-        }
-
-        if IsKeyPressed(KEY_RIGHT) || IsKeyPressedRepeat(KEY_RIGHT) {
-            if IsKeyDown(KEY_LEFT_SHIFT) {
-                if IsKeyDown(KEY_LEFT_CONTROL) {
-                    w.cursor.b = SeekOnWordBoundary(w.buffer, w.cursor.b, GO_FORWARD);
-                } else {
-                    w.cursor.b = MoveRight(w.buffer, w.cursor.b);
-                }
-            } else {
-                if IsKeyDown(KEY_LEFT_CONTROL) {
-                    w.cursor.a = SeekOnWordBoundary(w.buffer, w.cursor.a, GO_FORWARD);
-                    w.cursor.b = w.cursor.a;
-                } else {
-                    range := GetRange(w.cursor);
-                    if GetRangeSize(range) > 0 {
-                        w.cursor.a = MaxInt(w.cursor.a, w.cursor.b);
-                        w.cursor.b = MaxInt(w.cursor.a, w.cursor.b);
-                    } else {
-                        w.cursor.a = MoveRight(w.buffer, w.cursor.a);
-                        w.cursor.b = w.cursor.a;
-                    }
-                }
-            }
-        }
-
-        if (IsKeyPressed(KEY_DOWN) || IsKeyPressedRepeat(KEY_DOWN)) {
-            if IsKeyDown(KEY_LEFT_SHIFT) {
-                w.cursor.b = MoveDown(w.buffer, w.cursor.b);
-            } else {
-                range := GetRange(w.cursor);
-                if GetRangeSize(range) > 0 {
-                    w.cursor.b = range.max;
-                    w.cursor.a = range.max;
-                }
-                w.cursor.a = MoveDown(w.buffer, w.cursor.a);
-                w.cursor.b = w.cursor.a;
-            }
-        }
-
-        if (IsKeyPressed(KEY_UP) || IsKeyPressedRepeat(KEY_UP)) {
-            if IsKeyDown(KEY_LEFT_SHIFT) {
-                w.cursor.b = MoveUp(w.buffer, w.cursor.b);
-            } else {
-                range := GetRange(w.cursor);
-                if GetRangeSize(range) > 0 {
-                    w.cursor.b = range.min;
-                    w.cursor.a = range.min;
-                }
-                w.cursor.a = MoveUp(w.buffer, w.cursor.a);
-                w.cursor.b = w.cursor.a;
-            }
-        }
-
-        if IsKeyPressed(KEY_BACKSPACE) || IsKeyPressedRepeat(KEY_BACKSPACE) {
-            range      := GetRange(w.cursor);
-            range_size := GetRangeSize(range);
-
-            if range_size == 0 {
-                if IsKeyDown(KEY_LEFT_CONTROL) {
-                    left := SeekOnWordBoundary(w.buffer, w.cursor.a, GO_BACKWARD);
-                    ReplaceText(w.buffer, {left, w.cursor.a}, "");
-                    w.cursor.a = left;
-                    w.cursor.b = w.cursor.a;
-                } else {
-                    left := MoveLeft(w.buffer, w.cursor.a);
-                    ReplaceText(w.buffer, {left, w.cursor.a}, "");
-                    w.cursor.a = left;
-                    w.cursor.b = w.cursor.a;
-                }
-            } else {
-                ReplaceText(w.buffer, range, "");
-                w.cursor.b = range.min;
-                w.cursor.a = w.cursor.b;
-            }
-        }
-
-        if IsKeyPressed(KEY_DELETE) || IsKeyPressedRepeat(KEY_DELETE) {
-            range      := GetRange(w.cursor);
-            range_size := GetRangeSize(range);
-
-            if range_size == 0 {
-                if IsKeyDown(KEY_LEFT_CONTROL) {
-                    right := SeekOnWordBoundary(w.buffer, w.cursor.a);
-                    ReplaceText(w.buffer, {w.cursor.a, right}, "");
-                } else {
-                    right := MoveRight(w.buffer, w.cursor.a);
-                    ReplaceText(w.buffer, {w.cursor.a, right}, "");
-                }
-                w.cursor.b = w.cursor.a;
-            } else {
-                ReplaceText(w.buffer, range, "");
-                w.cursor.b = range.min;
-                w.cursor.a = w.cursor.b;
-            }
-        }
-
-        if IsKeyPressed(KEY_ENTER) || IsKeyPressedRepeat(KEY_ENTER) {
-            ReplaceText(w.buffer, GetRange(w.cursor), "\n");
-            w.cursor.a = MoveRight(w.buffer, w.cursor.a);
-            w.cursor.b = w.cursor.a;
-        }
-
-        if IsKeyPressed(KEY_TAB) || IsKeyPressedRepeat(KEY_TAB) {
-            selection_range := GetRange(w.cursor);
-            ReplaceText(w.buffer, selection_range, "    ");
-            range_size := GetRangeSize(selection_range);
-            if range_size != 0 {
-                w.cursor.a = selection_range.min;
-                w.cursor.b = selection_range.min;
-            }
-            w.cursor.a = MoveRight(w.buffer, w.cursor.a + 3);
-            w.cursor.b = w.cursor.a;
-        }
-
-        if IsKeyPressed(KEY_HOME) {
-            line := FindLineOfPos(w.buffer, w.cursor.b);
-            if IsKeyDown(KEY_LEFT_SHIFT) {
-                w.cursor.b = line.range.min;
-            } else {
-                w.cursor.a = line.range.min;
-                w.cursor.b = line.range.min;
-            }
-        }
-        if IsKeyPressed(KEY_END) {
-            line := FindLineOfPos(w.buffer, w.cursor.b);
-            if IsKeyDown(KEY_LEFT_SHIFT) {
-                w.cursor.b = line.range.max;
-            } else {
-                w.cursor.a = line.range.max;
-                w.cursor.b = line.range.max;
-            }
-        }
-
-        if IsKeyPressed(KEY_PAGE_DOWN) || IsKeyPressedRepeat(KEY_PAGE_DOWN) {
-            vpos := CalculateVisualPos(w.buffer, w.cursor.b);
-            move_by := :int(roundf(GetRectY(text_window_rect) / Monosize.y));
-            vpos.y += move_by;
-            w.cursor.b = CalculatePosFromVisualPos(w.buffer, vpos);
-            if !IsKeyDown(KEY_LEFT_SHIFT) {
-                w.cursor.a = w.cursor.b;
-            }
-        }
-        if IsKeyPressed(KEY_PAGE_UP) || IsKeyPressedRepeat(KEY_PAGE_UP) {
-            vpos := CalculateVisualPos(w.buffer, w.cursor.b);
-            move_by := :int(roundf(GetRectY(text_window_rect) / Monosize.y));
-            vpos.y -= move_by;
-            w.cursor.b = CalculatePosFromVisualPos(w.buffer, vpos);
-            if !IsKeyDown(KEY_LEFT_SHIFT) {
-                w.cursor.a = w.cursor.b;
-            }
-        }
-
-
-        for key := GetCharPressed(); key; key = GetCharPressed() {
-            selection_range := GetRange(w.cursor);
-
-            result: UTF8_Result = UTF32ToUTF8(:u32(key));
-            if result.error == 0 {
-                ReplaceText(w.buffer, selection_range, {:*char(&result.out_str[0]), result.len});
-            } else {
-                ReplaceText(w.buffer, selection_range, "?");
-            }
-
-            range_size := GetRangeSize(selection_range);
-            if range_size != 0 {
-                w.cursor.a = selection_range.min;
-                w.cursor.b = selection_range.min;
-            }
-            w.cursor.a = MoveRight(w.buffer, w.cursor.a);
-            w.cursor.b = w.cursor.a;
-        }
-
-        //
-        // Scrolling
-        //
-        mouse_wheel := GetMouseWheelMove() * 48;
-        w.scroll.y -= mouse_wheel;
-
-        if initial_cursor.b != w.cursor.b {
-            cursor_vpos := CalculateVisualPos(w.buffer, w.cursor.b);
-
-            world_pos            := CalculateWorldPosUnscrolled(cursor_vpos);
-            world_pos_cursor_end := Vector2Add(world_pos, Monosize);
-
-            scrolled_begin := w.scroll;
-            scrolled_end   := Vector2Add(w.scroll, GetRectSize(text_window_rect));
-
-            if world_pos_cursor_end.x > scrolled_end.x {
-                w.scroll.x += world_pos_cursor_end.x - scrolled_end.x;
-            }
-            if world_pos.x < scrolled_begin.x {
-                w.scroll.x -= scrolled_begin.x - world_pos.x;
-            }
-            if world_pos_cursor_end.y > scrolled_end.y {
-                w.scroll.y += world_pos_cursor_end.y - scrolled_end.y;
-            }
-            if world_pos.y < scrolled_begin.y {
-                w.scroll.y -= scrolled_begin.y - world_pos.y;
-            }
-        }
-        if (w.scroll.x < 0) w.scroll.x = 0;
-        if (w.scroll.y < 0) w.scroll.y = 0;
-        if (w.scroll.y > buffer_end_wpos.y) w.scroll.y = buffer_end_wpos.y;
-
-        //
-        // Mouse
-        //
-        mouse_p := GetMousePosition();
-        if CheckCollisionPointRec(mouse_p, Rect2PToRectangle(w.rect)) {
-            if CheckCollisionPointRec(mouse_p, Rect2PToRectangle(text_window_rect)) && !w.mouse_scrolling {
-                if IsMouseButtonPressed(MOUSE_BUTTON_LEFT) {
-                    p := Vector2Add(mouse_p, w.scroll);
-                    p  = Vector2Subtract(p, text_window_rect.min);
-                    p  = Vector2Divide(p, Monosize);
-                    x := :int(floorf(p.x));
-                    y := :int(floorf(p.y));
-                    w.cursor.a = CalculatePosFromVisualPos(w.buffer, {x, y});
-                    w.cursor.b = w.cursor.a;
-                } else if IsMouseButtonDown(MOUSE_BUTTON_LEFT) {
-                    p := Vector2Add(mouse_p, w.scroll);
-                    p  = Vector2Subtract(p, text_window_rect.min);
-                    p  = Vector2Divide(p, Monosize);
-                    x := :int(floorf(p.x));
-                    y := :int(floorf(p.y));
-                    w.cursor.b = CalculatePosFromVisualPos(w.buffer, {x, y});
-                }
-                SetMouseCursor(MOUSE_CURSOR_IBEAM);
-            } else {
-                SetMouseCursor(MOUSE_CURSOR_DEFAULT);
-
-                if IsMouseButtonPressed(MOUSE_BUTTON_LEFT) {
-                    w.mouse_scrolling = true;
-                }
-            }
-        }
-
-        if w.mouse_scrolling {
-            mouse_scroll_marker_normalized := (mouse_p.y - w.rect.min.y) / GetRectY(bar);
-            w.scroll.y = mouse_scroll_marker_normalized * buffer_end_wpos.y;
-
-            if IsMouseButtonReleased(MOUSE_BUTTON_LEFT) w.mouse_scrolling = false;
-        }
-    }
-
-    buffer_pixel_size := GetRectSize(text_window_rect);
-    _miny := w.scroll.y / Monosize.y;
-    _maxy := (w.scroll.y + buffer_pixel_size.y) / Monosize.y;
-
-    _minx := w.scroll.x / Monosize.x;
-    _maxx := (w.scroll.x + buffer_pixel_size.x) / Monosize.x;
-
-    miny := :int(floorf(_miny));
-    minx := :int(floorf(_minx));
-
-    maxy := :int(ceilf(_maxy));
-    maxx := :int(ceilf(_maxx));
-
-    // Draw grid
-    if 0 {
-        for y := miny; y < maxy; y += 1 {
-            for x := minx; x < maxx; x += 1 {
-                p := CalculateWorldPos(w.scroll, {x, y});
-                rect := Rect2PSize(p.x, p.y, Monosize.x, Monosize.y);
-                rect = Shrink(rect, 1);
-                DrawRect(rect, {255, 0, 0, 40});
-            }
-        }
-    }
-
-    BeginScissorMode(:int(w.rect.min.x), :int(w.rect.min.y), :int(GetRectX(w.rect)), :int(GetRectY(w.rect)));
-
-    // Draw text and line numbers
-    {
-        FONT_SPACING :: 1;
-
-        DrawRect(line_numbers_rect, LIGHTGRAY);
-        miny = ClampInt(miny, 0, w.buffer.lines.len - 1);
-        maxy = ClampInt(maxy, 0, w.buffer.lines.len - 1);
-        for y := miny; y <= maxy; y += 1 {
-            line_range := w.buffer.lines.data[y];
-
-            string := AllocStringFromBuffer(w.buffer, line_range, null_terminate = true);
-            defer free(string.str);
-
-            pos := CalculateWorldPos(w.scroll, {0, y});
-            pos_adjusted_by_buffer := Vector2Add(pos, text_window_rect.min);
-            DrawTextEx(font, string.str, pos_adjusted_by_buffer, font_size, FONT_SPACING, BLACK);
-
-            line_number_pos: Vector2 = {w.rect.min.x, pos_adjusted_by_buffer.y};
-            line_number_string := TextFormat("%d", y);
-            DrawTextEx(font, line_number_string, line_number_pos, font_size, FONT_SPACING, GRAY);
-        }
-    }
-
-    // Draw selection
-    {
-        range := GetRange(w.cursor);
-        start_vpos := CalculateVisualPos(w.buffer, range.min);
-        pos := start_vpos;
-        for iter := Iterate(w.buffer, range.min, range.max); IsValid(iter); Advance(&iter) {
-            world_pos := CalculateWorldPos(w.scroll, pos);
-            world_pos_adjusted_by_buffer := Vector2Add(world_pos, text_window_rect.min);
-
-            rect := Rect2PSize(world_pos_adjusted_by_buffer.x, world_pos_adjusted_by_buffer.y, Monosize.x, Monosize.y);
-            DrawRect(rect, {0, 255, 0, 40});
-
-            pos.x += 1;
-            if iter.item == '\n' {
-                pos.x = 0;
-                pos.y += 1;
-            }
-        }
-    }
-
-    // Draw cursor
-    {
-        c := CalculateVisualPos(w.buffer, w.cursor.b);
-        p := CalculateWorldPos(w.scroll, c);
-        pos_adjusted_by_buffer := Vector2Add(p, text_window_rect.min);
-
-        cursor_size: f32 = Monosize.x * 0.2;
-        rect := Rect2PSize(pos_adjusted_by_buffer.x, pos_adjusted_by_buffer.y, Monosize.x, Monosize.y);
-        rect = CutLeft(&rect, cursor_size);
-
-        DrawRect(rect, RED);
-    }
-
-    EndScissorMode();
-
-
-    // Draw bar
-    {
-        DrawRect(bar, LIGHTGRAY);
-
-        scroll_start_normalized := :f32(w.scroll.y) / :f32(buffer_end_wpos.y);
-        scroll_start := scroll_start_normalized * GetRectSize(bar).y;
-        CutTop(&bar, scroll_start);
-        marker := CutTop(&bar, 20);
-        DrawRect(marker, GRAY);
-    }
-
-    if w != FocusedWindow {
-        DrawRect(w.rect, {0,0,0,20});
-    }
-}
-
 InvalidCodepath :: proc() {
     assert(:*char("invalid codepath") == :*char(""));
 }
 
-
 main :: proc(): int {
     InitWindow(800, 600, "TextEditor");
     SetWindowState(FLAG_WINDOW_RESIZABLE | FLAG_WINDOW_MAXIMIZED);
@@ -457,28 +25,80 @@ main :: proc(): int {
     font_spacing: float = 1;
     font: Font = LoadFontEx("C:/Windows/Fonts/consola.ttf", :int(font_size), nil, 0);
 
-    glyph_info: GlyphInfo = GetGlyphInfo(font, 'A');
-    size := MeasureTextEx(font, "A", font_size, font_spacing);
-    Monosize = {:float(glyph_info.image.width), size.y};
-
-    buffer: Buffer;
-    file_content := LoadFileText("C:/Work/language/examples/text_editor/main.lc");
-    AddText(&buffer, {file_content, :int(strlen(file_content))});
-    UnloadFileText(file_content);
-
-    AddWindow({buffer = &buffer});
-    AddWindow({buffer = &buffer});
-    FocusedWindow = &WindowStack[0];
+    SANDBOX_TEXT_EDITOR :: 1;
+    SANDBOX_PROTOTYPE :: 2;
+    sandbox_chosen := SANDBOX_TEXT_EDITOR;
 
     for !WindowShouldClose() {
         screen_size: Vector2 = {:f32(GetScreenWidth()), :f32(GetScreenHeight())};
         screen_rect := Rect2PSize(0, 0, screen_size.x, screen_size.y);
-        ComputeWindowRects(screen_rect);
+        top_bar := CutTop(&screen_rect, 30);
+        top_bar_original := top_bar;
 
+        button1_text := "Text Editor";
+        button1_text_size := MeasureTextEx(font, button1_text, font_size, font_spacing);
+        button1 := CutLeft(&top_bar, :float(button1_text_size.x) * 1.5);
+        button1 = Shrink(button1, 4);
+        button1_text_pos: Vector2 = {
+            x = button1.min.x + (GetRectX(button1) - :float(button1_text_size.x)) * 0.5,
+            y = button1.min.y + (GetRectY(button1) - :float(button1_text_size.y)) * 0.7,
+        };
+
+        button1_hover := false;
+        button1_click := false;
+        if CheckCollisionPointRec(GetMousePosition(), Rect2PToRectangle(button1)) {
+            button1_hover = true;
+            if IsMouseButtonPressed(MOUSE_BUTTON_LEFT) {
+                button1_click = true;
+            }
+        }
+
+        button2_text := "Prototype";
+        button2_text_size := MeasureTextEx(font, button2_text, font_size, font_spacing);
+        button2 := CutLeft(&top_bar, :float(button2_text_size.x) * 1.5);
+        button2 = Shrink(button2, 4);
+        button2_text_pos: Vector2 = {
+            x = button2.min.x + (GetRectX(button2) - :float(button2_text_size.x)) * 0.5,
+            y = button2.min.y + (GetRectY(button2) - :float(button2_text_size.y)) * 0.7,
+        };
+
+        button2_hover := false;
+        button2_click := false;
+        if CheckCollisionPointRec(GetMousePosition(), Rect2PToRectangle(button2)) {
+            button2_hover = true;
+            if IsMouseButtonPressed(MOUSE_BUTTON_LEFT) {
+                button2_click = true;
+            }
+        }
+
+        if button1_click {
+            sandbox_chosen = SANDBOX_TEXT_EDITOR;
+        } else if button2_click {
+            sandbox_chosen = SANDBOX_PROTOTYPE;
+        }
 
         BeginDrawing();
         ClearBackground(RAYWHITE);
-        UpdateAndDrawWindows(font, font_size);
+
+        if sandbox_chosen == SANDBOX_TEXT_EDITOR {
+            if !TeInited InitTextEditor(font, font_size, font_spacing);
+            ComputeWindowRects(screen_rect);
+            UpdateAndDrawWindows(font, font_size);
+        } else if sandbox_chosen == SANDBOX_PROTOTYPE {
+
+        }
+
+        DrawRect(top_bar_original, LIGHTGRAY);
+
+        DrawRectangleRoundedLines(Rect2PToRectangle(button1), 0.3, 12, 2, BLACK);
+        if button1_hover DrawRectangleRounded(Rect2PToRectangle(button1), 0.3, 12, WHITE);
+        DrawTextEx(font, button1_text, button1_text_pos, font_size, font_spacing, BLACK);
+
+        DrawRectangleRoundedLines(Rect2PToRectangle(button2), 0.3, 12, 2, BLACK);
+        if button2_hover DrawRectangleRounded(Rect2PToRectangle(button2), 0.3, 12, WHITE);
+        DrawTextEx(font, button2_text, button2_text_pos, font_size, font_spacing, BLACK);
+
+
         EndDrawing();
     }
     CloseWindow();
diff --git a/examples/text_editor/rect2p.lc b/examples/text_editor/rect2p.lc
index 52ba302..4903e3d 100644
--- a/examples/text_editor/rect2p.lc
+++ b/examples/text_editor/rect2p.lc
@@ -3,22 +3,6 @@ Rect2P :: struct {
     max: Vector2;
 }
 
-F32_Max :: proc(a: f32, b: f32): f32 {
-    if a > b return a;
-    return b;
-}
-
-F32_Min :: proc(a: f32, b: f32): f32 {
-    if a > b return b;
-    return a;
-}
-
-F32_Clamp :: proc(val: f32, min: f32, max: f32): f32 {
-    if (val > max) return max;
-    if (val < min) return min;
-    return val;
-}
-
 GetRectSize :: proc(rect: Rect2P): Vector2 {
     result: Vector2 = {rect.max.x - rect.min.x, rect.max.y - rect.min.y};
     return result;
@@ -36,7 +20,7 @@ GetRectX :: proc(rect: Rect2P): f32 {
 
 CutLeft :: proc(r: *Rect2P, value: f32): Rect2P {
     minx := r.min.x;
-    r.min.x = F32_Min(r.max.x, r.min.x + value);
+    r.min.x = MinFloat(r.max.x, r.min.x + value);
     return :Rect2P{
         {    minx, r.min.y},
         {r.min.x, r.max.y},
@@ -45,7 +29,7 @@ CutLeft :: proc(r: *Rect2P, value: f32): Rect2P {
 
 CutRight :: proc(r: *Rect2P, value: f32): Rect2P {
     maxx := r.max.x;
-    r.max.x = F32_Max(r.max.x - value, r.min.x);
+    r.max.x = MaxFloat(r.max.x - value, r.min.x);
     return :Rect2P{
         {r.max.x, r.min.y},
         {    maxx, r.max.y},
@@ -54,7 +38,7 @@ CutRight :: proc(r: *Rect2P, value: f32): Rect2P {
 
 CutBottom :: proc(r: *Rect2P, value: f32): Rect2P { // Y is down
     maxy := r.max.y;
-    r.max.y = F32_Max(r.min.y, r.max.y - value);
+    r.max.y = MaxFloat(r.min.y, r.max.y - value);
     return :Rect2P{
         {r.min.x, r.max.y},
         {r.max.x,     maxy},
@@ -63,7 +47,7 @@ CutBottom :: proc(r: *Rect2P, value: f32): Rect2P { // Y is down
 
 CutTop :: proc(r: *Rect2P, value: f32): Rect2P { // Y is down
     miny := r.min.y;
-    r.min.y = F32_Min(r.min.y + value, r.max.y);
+    r.min.y = MinFloat(r.min.y + value, r.max.y);
     return :Rect2P{
         {r.min.x,     miny},
         {r.max.x, r.min.y},
diff --git a/examples/text_editor/text_editor.lc b/examples/text_editor/text_editor.lc
new file mode 100644
index 0000000..a66199e
--- /dev/null
+++ b/examples/text_editor/text_editor.lc
@@ -0,0 +1,470 @@
+TeInited := false;
+TeFontSize: float = 14;
+TeFontSpacing: float = 1;
+TeFont: Font;
+TeBuffer: Buffer;
+
+FocusedWindow: *Window;
+WindowStack: [8]Window;
+WindowStackCount: int;
+
+InitTextEditor :: proc(font: Font, font_size: float, font_spacing: float) {
+    TeInited = true;
+    TeFont = font;
+    TeFontSpacing = font_spacing;
+    TeFontSize = font_size;
+
+    glyph_info: GlyphInfo = GetGlyphInfo(TeFont, 'A');
+    size := MeasureTextEx(TeFont, "A", TeFontSize, TeFontSpacing);
+    Monosize = {:float(glyph_info.image.width), size.y};
+
+    file_content := LoadFileText("C:/Work/language/examples/text_editor/main.lc");
+    AddText(&TeBuffer, {file_content, :int(strlen(file_content))});
+    UnloadFileText(file_content);
+
+    AddWindow({buffer = &TeBuffer});
+    AddWindow({buffer = &TeBuffer});
+    FocusedWindow = &WindowStack[0];
+}
+
+Window :: struct {
+    buffer: *Buffer;
+    cursor: Selection;
+    scroll: Vector2;
+    mouse_scrolling: bool;
+
+    rect: Rect2P;
+}
+
+Selection :: struct {
+    a: int;
+    b: int;
+}
+
+GetRange :: proc(s: Selection): Range {
+    result: Range = {MinInt(s.a, s.b), MaxInt(s.a, s.b)};
+    return result;
+}
+
+AddWindow :: proc(window: Window) {
+    if (WindowStackCount + 1 >= 8) return;
+
+    WindowStack[WindowStackCount] = window;
+    WindowStackCount += 1;
+}
+
+ComputeWindowRects :: proc(screen_rect: Rect2P) {
+    WindowStack[0].rect = CutLeft(&screen_rect, 0.5 * GetRectX(screen_rect));
+    WindowStack[1].rect = CutLeft(&screen_rect, 1.0 * GetRectX(screen_rect));
+}
+
+UpdateAndDrawWindows :: proc(font: Font, font_size: float) {
+    SetMouseCursor(MOUSE_CURSOR_DEFAULT);
+    for i := 0; i < WindowStackCount; i += 1 {
+        window: *Window = &WindowStack[i];
+        UpdateAndDrawWindow(window, font, font_size);
+    }
+}
+
+UpdateAndDrawWindow :: proc(w: *Window, font: Font, font_size: float) {
+    initial_cursor: Selection = w.cursor;
+    text_window_rect := w.rect;
+    bar_rect := CutRight(&text_window_rect, 10);
+    horizontal_bar_rect := CutBottom(&text_window_rect, 10);
+    horizontal_bar_rect; @unused
+    // line_numbers_rect := CutLeft(&text_window_rect, Monosize.x * 4);
+
+    buffer_end_vpos := CalculateVisualPos(w.buffer, w.buffer.len - 1);
+    buffer_end_wpos := CalculateWorldPosUnscrolled(buffer_end_vpos);
+
+    if CheckCollisionPointRec(GetMousePosition(), Rect2PToRectangle(w.rect)) {
+        if w != FocusedWindow {
+            SetMouseCursor(MOUSE_CURSOR_POINTING_HAND);
+        }
+        if IsMouseButtonPressed(MOUSE_BUTTON_LEFT) {
+            FocusedWindow = w;
+        }
+    }
+
+
+    if w == FocusedWindow {
+        if IsKeyPressed(KEY_LEFT) || IsKeyPressedRepeat(KEY_LEFT) {
+            if IsKeyDown(KEY_LEFT_SHIFT) {
+                if IsKeyDown(KEY_LEFT_CONTROL) {
+                    w.cursor.b = SeekOnWordBoundary(w.buffer, w.cursor.b, GO_BACKWARD);
+                } else {
+                    w.cursor.b = MoveLeft(w.buffer, w.cursor.b);
+                }
+            } else {
+                if IsKeyDown(KEY_LEFT_CONTROL) {
+                    w.cursor.a = SeekOnWordBoundary(w.buffer, w.cursor.a, GO_BACKWARD);
+                    w.cursor.b = w.cursor.a;
+                } else {
+                    range := GetRange(w.cursor);
+                    if GetRangeSize(range) > 0 {
+                        w.cursor.a = MinInt(w.cursor.a, w.cursor.b);
+                        w.cursor.b = MinInt(w.cursor.a, w.cursor.b);
+                    } else {
+                        w.cursor.a = MoveLeft(w.buffer, w.cursor.a);
+                        w.cursor.b = w.cursor.a;
+                    }
+                }
+            }
+        }
+
+        if IsKeyPressed(KEY_RIGHT) || IsKeyPressedRepeat(KEY_RIGHT) {
+            if IsKeyDown(KEY_LEFT_SHIFT) {
+                if IsKeyDown(KEY_LEFT_CONTROL) {
+                    w.cursor.b = SeekOnWordBoundary(w.buffer, w.cursor.b, GO_FORWARD);
+                } else {
+                    w.cursor.b = MoveRight(w.buffer, w.cursor.b);
+                }
+            } else {
+                if IsKeyDown(KEY_LEFT_CONTROL) {
+                    w.cursor.a = SeekOnWordBoundary(w.buffer, w.cursor.a, GO_FORWARD);
+                    w.cursor.b = w.cursor.a;
+                } else {
+                    range := GetRange(w.cursor);
+                    if GetRangeSize(range) > 0 {
+                        w.cursor.a = MaxInt(w.cursor.a, w.cursor.b);
+                        w.cursor.b = MaxInt(w.cursor.a, w.cursor.b);
+                    } else {
+                        w.cursor.a = MoveRight(w.buffer, w.cursor.a);
+                        w.cursor.b = w.cursor.a;
+                    }
+                }
+            }
+        }
+
+        if (IsKeyPressed(KEY_DOWN) || IsKeyPressedRepeat(KEY_DOWN)) {
+            if IsKeyDown(KEY_LEFT_SHIFT) {
+                w.cursor.b = MoveDown(w.buffer, w.cursor.b);
+            } else {
+                range := GetRange(w.cursor);
+                if GetRangeSize(range) > 0 {
+                    w.cursor.b = range.max;
+                    w.cursor.a = range.max;
+                }
+                w.cursor.a = MoveDown(w.buffer, w.cursor.a);
+                w.cursor.b = w.cursor.a;
+            }
+        }
+
+        if (IsKeyPressed(KEY_UP) || IsKeyPressedRepeat(KEY_UP)) {
+            if IsKeyDown(KEY_LEFT_SHIFT) {
+                w.cursor.b = MoveUp(w.buffer, w.cursor.b);
+            } else {
+                range := GetRange(w.cursor);
+                if GetRangeSize(range) > 0 {
+                    w.cursor.b = range.min;
+                    w.cursor.a = range.min;
+                }
+                w.cursor.a = MoveUp(w.buffer, w.cursor.a);
+                w.cursor.b = w.cursor.a;
+            }
+        }
+
+        if IsKeyPressed(KEY_BACKSPACE) || IsKeyPressedRepeat(KEY_BACKSPACE) {
+            range      := GetRange(w.cursor);
+            range_size := GetRangeSize(range);
+
+            if range_size == 0 {
+                if IsKeyDown(KEY_LEFT_CONTROL) {
+                    left := SeekOnWordBoundary(w.buffer, w.cursor.a, GO_BACKWARD);
+                    ReplaceText(w.buffer, {left, w.cursor.a}, "");
+                    w.cursor.a = left;
+                    w.cursor.b = w.cursor.a;
+                } else {
+                    left := MoveLeft(w.buffer, w.cursor.a);
+                    ReplaceText(w.buffer, {left, w.cursor.a}, "");
+                    w.cursor.a = left;
+                    w.cursor.b = w.cursor.a;
+                }
+            } else {
+                ReplaceText(w.buffer, range, "");
+                w.cursor.b = range.min;
+                w.cursor.a = w.cursor.b;
+            }
+        }
+
+        if IsKeyPressed(KEY_DELETE) || IsKeyPressedRepeat(KEY_DELETE) {
+            range      := GetRange(w.cursor);
+            range_size := GetRangeSize(range);
+
+            if range_size == 0 {
+                if IsKeyDown(KEY_LEFT_CONTROL) {
+                    right := SeekOnWordBoundary(w.buffer, w.cursor.a);
+                    ReplaceText(w.buffer, {w.cursor.a, right}, "");
+                } else {
+                    right := MoveRight(w.buffer, w.cursor.a);
+                    ReplaceText(w.buffer, {w.cursor.a, right}, "");
+                }
+                w.cursor.b = w.cursor.a;
+            } else {
+                ReplaceText(w.buffer, range, "");
+                w.cursor.b = range.min;
+                w.cursor.a = w.cursor.b;
+            }
+        }
+
+        if IsKeyPressed(KEY_ENTER) || IsKeyPressedRepeat(KEY_ENTER) {
+            ReplaceText(w.buffer, GetRange(w.cursor), "\n");
+            w.cursor.a = MoveRight(w.buffer, w.cursor.a);
+            w.cursor.b = w.cursor.a;
+        }
+
+        if IsKeyPressed(KEY_TAB) || IsKeyPressedRepeat(KEY_TAB) {
+            selection_range := GetRange(w.cursor);
+            ReplaceText(w.buffer, selection_range, "    ");
+            range_size := GetRangeSize(selection_range);
+            if range_size != 0 {
+                w.cursor.a = selection_range.min;
+                w.cursor.b = selection_range.min;
+            }
+            w.cursor.a = MoveRight(w.buffer, w.cursor.a + 3);
+            w.cursor.b = w.cursor.a;
+        }
+
+        if IsKeyPressed(KEY_HOME) {
+            line := FindLineOfPos(w.buffer, w.cursor.b);
+            if IsKeyDown(KEY_LEFT_SHIFT) {
+                w.cursor.b = line.range.min;
+            } else {
+                w.cursor.a = line.range.min;
+                w.cursor.b = line.range.min;
+            }
+        }
+        if IsKeyPressed(KEY_END) {
+            line := FindLineOfPos(w.buffer, w.cursor.b);
+            if IsKeyDown(KEY_LEFT_SHIFT) {
+                w.cursor.b = line.range.max;
+            } else {
+                w.cursor.a = line.range.max;
+                w.cursor.b = line.range.max;
+            }
+        }
+
+        // @todo: buffer.len abstract
+        if IsKeyDown(KEY_LEFT_CONTROL) && IsKeyPressed(KEY_A) {
+            w.cursor.a = 0;
+            w.cursor.b = w.buffer.len - 1;
+        }
+
+        if IsKeyPressed(KEY_PAGE_DOWN) || IsKeyPressedRepeat(KEY_PAGE_DOWN) {
+            vpos := CalculateVisualPos(w.buffer, w.cursor.b);
+            move_by := :int(roundf(GetRectY(text_window_rect) / Monosize.y));
+            vpos.y += move_by;
+            w.cursor.b = CalculatePosFromVisualPos(w.buffer, vpos);
+            if !IsKeyDown(KEY_LEFT_SHIFT) {
+                w.cursor.a = w.cursor.b;
+            }
+        }
+        if IsKeyPressed(KEY_PAGE_UP) || IsKeyPressedRepeat(KEY_PAGE_UP) {
+            vpos := CalculateVisualPos(w.buffer, w.cursor.b);
+            move_by := :int(roundf(GetRectY(text_window_rect) / Monosize.y));
+            vpos.y -= move_by;
+            w.cursor.b = CalculatePosFromVisualPos(w.buffer, vpos);
+            if !IsKeyDown(KEY_LEFT_SHIFT) {
+                w.cursor.a = w.cursor.b;
+            }
+        }
+
+
+        for key := GetCharPressed(); key; key = GetCharPressed() {
+            selection_range := GetRange(w.cursor);
+
+            result: UTF8_Result = UTF32ToUTF8(:u32(key));
+            if result.error == 0 {
+                ReplaceText(w.buffer, selection_range, {:*char(&result.out_str[0]), result.len});
+            } else {
+                ReplaceText(w.buffer, selection_range, "?");
+            }
+
+            range_size := GetRangeSize(selection_range);
+            if range_size != 0 {
+                w.cursor.a = selection_range.min;
+                w.cursor.b = selection_range.min;
+            }
+            w.cursor.a = MoveRight(w.buffer, w.cursor.a);
+            w.cursor.b = w.cursor.a;
+        }
+
+        //
+        // Scrolling
+        //
+        mouse_wheel := GetMouseWheelMove() * 48;
+        w.scroll.y -= mouse_wheel;
+
+        if initial_cursor.b != w.cursor.b {
+            cursor_vpos := CalculateVisualPos(w.buffer, w.cursor.b);
+
+            world_pos            := CalculateWorldPosUnscrolled(cursor_vpos);
+            world_pos_cursor_end := Vector2Add(world_pos, Monosize);
+
+            scrolled_begin := w.scroll;
+            scrolled_end   := Vector2Add(w.scroll, GetRectSize(text_window_rect));
+
+            if world_pos_cursor_end.x > scrolled_end.x {
+                w.scroll.x += world_pos_cursor_end.x - scrolled_end.x;
+            }
+            if world_pos.x < scrolled_begin.x {
+                w.scroll.x -= scrolled_begin.x - world_pos.x;
+            }
+            if world_pos_cursor_end.y > scrolled_end.y {
+                w.scroll.y += world_pos_cursor_end.y - scrolled_end.y;
+            }
+            if world_pos.y < scrolled_begin.y {
+                w.scroll.y -= scrolled_begin.y - world_pos.y;
+            }
+        }
+        if (w.scroll.x < 0) w.scroll.x = 0;
+        if (w.scroll.y < 0) w.scroll.y = 0;
+
+        adjusted_kind_of_end := buffer_end_wpos.y - GetRectY(text_window_rect) * 0.8;
+        if (w.scroll.y > adjusted_kind_of_end) w.scroll.y = adjusted_kind_of_end;
+
+        //
+        // Mouse
+        //
+        mouse_p := GetMousePosition();
+        if CheckCollisionPointRec(mouse_p, Rect2PToRectangle(w.rect)) {
+            if CheckCollisionPointRec(mouse_p, Rect2PToRectangle(text_window_rect)) && !w.mouse_scrolling {
+                if IsMouseButtonPressed(MOUSE_BUTTON_LEFT) {
+                    p := Vector2Add(mouse_p, w.scroll);
+                    p  = Vector2Subtract(p, text_window_rect.min);
+                    p  = Vector2Divide(p, Monosize);
+                    x := :int(floorf(p.x));
+                    y := :int(floorf(p.y));
+                    w.cursor.a = CalculatePosFromVisualPos(w.buffer, {x, y});
+                    w.cursor.b = w.cursor.a;
+                }
+                SetMouseCursor(MOUSE_CURSOR_IBEAM);
+            } else {
+                SetMouseCursor(MOUSE_CURSOR_DEFAULT);
+
+                if IsMouseButtonPressed(MOUSE_BUTTON_LEFT) {
+                    w.mouse_scrolling = true;
+                }
+            }
+        }
+
+        if IsMouseButtonDown(MOUSE_BUTTON_LEFT) {
+            SetMouseCursor(MOUSE_CURSOR_DEFAULT);
+            p := Vector2Add(mouse_p, w.scroll);
+            p  = Vector2Subtract(p, text_window_rect.min);
+            p  = Vector2Divide(p, Monosize);
+            x := :int(floorf(p.x));
+            y := :int(floorf(p.y));
+            w.cursor.b = CalculatePosFromVisualPos(w.buffer, {x, y});
+        }
+
+        if w.mouse_scrolling {
+            mouse_scroll_marker_normalized := (mouse_p.y - w.rect.min.y) / GetRectY(bar_rect);
+            w.scroll.y = mouse_scroll_marker_normalized * buffer_end_wpos.y;
+
+            if IsMouseButtonReleased(MOUSE_BUTTON_LEFT) w.mouse_scrolling = false;
+        }
+    }
+
+    buffer_pixel_size := GetRectSize(text_window_rect);
+    _miny := w.scroll.y / Monosize.y;
+    _maxy := (w.scroll.y + buffer_pixel_size.y) / Monosize.y;
+
+    _minx := w.scroll.x / Monosize.x;
+    _maxx := (w.scroll.x + buffer_pixel_size.x) / Monosize.x;
+
+    miny := :int(floorf(_miny));
+    minx := :int(floorf(_minx));
+
+    maxy := :int(ceilf(_maxy));
+    maxx := :int(ceilf(_maxx));
+
+    // Draw grid
+    if 0 {
+        for y := miny; y < maxy; y += 1 {
+            for x := minx; x < maxx; x += 1 {
+                p := CalculateWorldPos(w.scroll, {x, y});
+                rect := Rect2PSize(p.x, p.y, Monosize.x, Monosize.y);
+                rect = Shrink(rect, 1);
+                DrawRect(rect, {255, 0, 0, 40});
+            }
+        }
+    }
+
+    BeginScissorMode(:int(w.rect.min.x), :int(w.rect.min.y), :int(GetRectX(w.rect)), :int(GetRectY(w.rect)));
+
+    // Draw text and line numbers
+    {
+        FONT_SPACING :: 1;
+
+        // DrawRect(line_numbers_rect, LIGHTGRAY);
+        miny = ClampInt(miny, 0, w.buffer.lines.len - 1);
+        maxy = ClampInt(maxy, 0, w.buffer.lines.len - 1);
+        for y := miny; y <= maxy; y += 1 {
+            line_range := w.buffer.lines.data[y];
+
+            string := AllocStringFromBuffer(w.buffer, line_range, null_terminate = true);
+            defer free(string.str);
+
+            pos := CalculateWorldPos(w.scroll, {0, y});
+            pos_adjusted_by_buffer := Vector2Add(pos, text_window_rect.min);
+            DrawTextEx(font, string.str, pos_adjusted_by_buffer, font_size, FONT_SPACING, BLACK);
+
+            // line_number_pos: Vector2 = {w.rect.min.x, pos_adjusted_by_buffer.y};
+            // line_number_string := TextFormat("%d", y);
+            // DrawTextEx(font, line_number_string, line_number_pos, font_size, FONT_SPACING, GRAY);
+        }
+    }
+
+    // Draw selection
+    {
+        range := GetRange(w.cursor);
+        start_vpos := CalculateVisualPos(w.buffer, range.min);
+        pos := start_vpos;
+        for iter := Iterate(w.buffer, range.min, range.max); IsValid(iter); Advance(&iter) {
+            world_pos := CalculateWorldPos(w.scroll, pos);
+            world_pos_adjusted_by_buffer := Vector2Add(world_pos, text_window_rect.min);
+
+            rect := Rect2PSize(world_pos_adjusted_by_buffer.x, world_pos_adjusted_by_buffer.y, Monosize.x, Monosize.y);
+            DrawRect(rect, {0, 92, 222, 40});
+
+            pos.x += 1;
+            if iter.item == '\n' {
+                pos.x = 0;
+                pos.y += 1;
+            }
+        }
+    }
+
+    // Draw cursor
+    {
+        c := CalculateVisualPos(w.buffer, w.cursor.b);
+        p := CalculateWorldPos(w.scroll, c);
+        pos_adjusted_by_buffer := Vector2Add(p, text_window_rect.min);
+
+        cursor_size: f32 = Monosize.x * 0.2;
+        rect := Rect2PSize(pos_adjusted_by_buffer.x, pos_adjusted_by_buffer.y, Monosize.x, Monosize.y);
+        rect = CutLeft(&rect, cursor_size);
+
+        DrawRect(rect, RED);
+    }
+
+    EndScissorMode();
+
+
+    // Draw bar
+    {
+        DrawRect(bar_rect, LIGHTGRAY);
+        DrawRect(horizontal_bar_rect, LIGHTGRAY);
+
+        scroll_start_normalized := :f32(w.scroll.y) / :f32(buffer_end_wpos.y);
+        scroll_start := scroll_start_normalized * GetRectSize(bar_rect).y;
+        CutTop(&bar_rect, scroll_start);
+        marker := CutTop(&bar_rect, 20);
+        DrawRect(marker, GRAY);
+    }
+
+    if w != FocusedWindow {
+        DrawRect(w.rect, {0,0,0,20});
+    }
+}