Demos: Add Tubes :^)

Author: https://github.com/gmta
Commit: https://github.com/SerenityOS/serenity/commit/9dfe50170e
Pull-request: https://github.com/SerenityOS/serenity/pull/15171
Reviewed-by: https://github.com/linusg

Base/res/apps/Tubes.af

@@ -0,0 +1,4 @@
+[App]
+Name=Tubes
+Executable=/bin/Tubes
+Category=Demos

Userland/Demos/CMakeLists.txt

@@ -9,5 +9,6 @@ add_subdirectory(ModelGallery)
 add_subdirectory(Mouse)
 add_subdirectory(Screensaver)
 add_subdirectory(Starfield)
+add_subdirectory(Tubes)
 add_subdirectory(VirGLDemo)
 add_subdirectory(WidgetGallery)

Userland/Demos/Tubes/CMakeLists.txt

@@ -0,0 +1,13 @@
+serenity_component(
+    Tubes
+    TARGETS Tubes
+)
+
+set(SOURCES
+        Shapes.cpp
+        Tubes.cpp
+        main.cpp
+)
+
+serenity_app(Tubes ICON app-tubes)
+target_link_libraries(Tubes LibGUI LibCore LibGfx LibGL LibMain)

Userland/Demos/Tubes/Shapes.cpp

@@ -0,0 +1,82 @@
+/*
+ * Copyright (c) 2022, Jelle Raaijmakers <jelle@gmta.nl>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include <AK/Array.h>
+#include <Demos/Tubes/Shapes.h>
+#include <LibGL/GL/gl.h>
+#include <LibGfx/Vector3.h>
+#include <math.h>
+
+constexpr u8 sphere_number_of_segments = 4;
+constexpr u8 tube_number_of_segments = 12;
+
+void draw_sphere()
+{
+    // Draw a sphere by drawing a cube with many segments with normalized coordinates
+    glBegin(GL_QUADS);
+    auto draw_segment = [](Array<DoubleVector3, 4> corners, Optional<int> flip_a, Optional<int> flip_b, Optional<int> swap_a, Optional<int> swap_b) {
+        for (DoubleVector3& corner : corners) {
+            if (flip_a.has_value())
+                corner[flip_a.value()] *= -1;
+            if (flip_b.has_value())
+                corner[flip_b.value()] *= -1;
+            if (swap_a.has_value() && swap_b.has_value())
+                swap(corner[swap_a.value()], corner[swap_b.value()]);
+
+            glNormal3d(corner.x(), corner.y(), corner.z());
+            glVertex3d(corner.x(), corner.y(), corner.z());
+        }
+    };
+    double const segment_size = 2. / sphere_number_of_segments;
+    for (int y = 0; y < sphere_number_of_segments; y++) {
+        for (int x = 0; x < sphere_number_of_segments; x++) {
+            DoubleVector3 bottomleft = { -1. + x * segment_size, -1. + y * segment_size, 1. };
+            DoubleVector3 bottomright = { -1. + (x + 1) * segment_size, -1. + y * segment_size, 1. };
+            DoubleVector3 topright = { -1. + (x + 1) * segment_size, -1. + (y + 1) * segment_size, 1. };
+            DoubleVector3 topleft = { -1. + x * segment_size, -1. + (y + 1) * segment_size, 1. };
+
+            Array<DoubleVector3, 4> normalized_corners = {
+                bottomleft.normalized(),
+                bottomright.normalized(),
+                topright.normalized(),
+                topleft.normalized(),
+            };
+
+            draw_segment(normalized_corners, {}, {}, {}, {}); // front face
+            draw_segment(normalized_corners, 0, 2, {}, {});   // back face
+            draw_segment(normalized_corners, 2, {}, 0, 2);    // left face
+            draw_segment(normalized_corners, 0, {}, 0, 2);    // right face
+            draw_segment(normalized_corners, 1, {}, 1, 2);    // top face
+            draw_segment(normalized_corners, 2, {}, 1, 2);    // bottom face
+        }
+    }
+    glEnd();
+}
+
+void draw_tube()
+{
+    glBegin(GL_QUADS);
+    double const segment_angle = 2 * M_PI / tube_number_of_segments;
+    double last_x = 0.;
+    double last_y = 1.;
+    for (int i = 1; i <= tube_number_of_segments; ++i) {
+        double angle = i * segment_angle;
+        double segment_x = sin(angle);
+        double segment_y = cos(angle);
+
+        glNormal3d(last_x, last_y, 0.);
+        glVertex3d(last_x, last_y, 0.);
+        glNormal3d(segment_x, segment_y, 0.);
+        glVertex3d(segment_x, segment_y, 0.);
+        glVertex3d(segment_x, segment_y, -2.);
+        glNormal3d(last_x, last_y, 0.);
+        glVertex3d(last_x, last_y, -2.);
+
+        last_x = segment_x;
+        last_y = segment_y;
+    }
+    glEnd();
+}

Userland/Demos/Tubes/Shapes.h

@@ -0,0 +1,12 @@
+/*
+ * Copyright (c) 2022, Jelle Raaijmakers <jelle@gmta.nl>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#pragma once
+
+#include <AK/Types.h>
+
+void draw_sphere();
+void draw_tube();

Userland/Demos/Tubes/Tubes.cpp

@@ -0,0 +1,326 @@
+/*
+ * Copyright (c) 2022, Jelle Raaijmakers <jelle@gmta.nl>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include <AK/NumericLimits.h>
+#include <AK/Random.h>
+#include <Demos/Tubes/Shapes.h>
+#include <Demos/Tubes/Tubes.h>
+#include <LibGL/GLContext.h>
+#include <LibGUI/Application.h>
+#include <LibGUI/Event.h>
+#include <LibGUI/Painter.h>
+#include <LibGUI/Widget.h>
+#include <LibGfx/Bitmap.h>
+
+constexpr size_t grid_resolution = 15;
+constexpr int mouse_max_distance_move = 10;
+constexpr int reset_every_ticks = 900;
+constexpr double rotation_range = 35.;
+constexpr u8 tube_maximum_count = 12;
+constexpr u8 tube_minimum_count = 3;
+constexpr double tube_movement_per_tick = .25;
+constexpr double tube_relative_thickness = .6;
+constexpr int tube_travel_max_stretch = 6;
+
+static double random_double()
+{
+    return get_random<u32>() / static_cast<double>(NumericLimits<u32>::max());
+}
+
+static int random_int(int min, int max)
+{
+    return min + round_to<int>(random_double() * (max - min));
+}
+
+static IntVector4 tube_rotation_for_direction(Direction direction)
+{
+    switch (direction) {
+    case Direction::XPositive:
+        return { 0, 1, 0, -90 };
+    case Direction::XNegative:
+        return { 0, 1, 0, 90 };
+    case Direction::YPositive:
+        return { 1, 0, 0, 90 };
+    case Direction::YNegative:
+        return { 1, 0, 0, -90 };
+    case Direction::ZPositive:
+        return { 0, 1, 0, 180 };
+    case Direction::ZNegative:
+        return { 0, 0, 0, 0 };
+    default:
+        VERIFY_NOT_REACHED();
+    }
+}
+
+static IntVector3 vector_for_direction(Direction direction)
+{
+    switch (direction) {
+    case Direction::XPositive:
+        return { 1, 0, 0 };
+    case Direction::XNegative:
+        return { -1, 0, 0 };
+    case Direction::YPositive:
+        return { 0, 1, 0 };
+    case Direction::YNegative:
+        return { 0, -1, 0 };
+    case Direction::ZPositive:
+        return { 0, 0, 1 };
+    case Direction::ZNegative:
+        return { 0, 0, -1 };
+    default:
+        VERIFY_NOT_REACHED();
+    }
+}
+
+Tubes::Tubes(int interval)
+    : m_grid(MUST(FixedArray<u8>::try_create(grid_resolution * grid_resolution * grid_resolution)))
+{
+    start_timer(interval);
+}
+
+void Tubes::choose_new_direction_for_tube(Tube& tube)
+{
+    // Find all possible directions
+    Vector<Direction, 6> possible_directions;
+    for (int i = 1; i <= 6; ++i) {
+        auto direction = static_cast<Direction>(i);
+        auto direction_vector = vector_for_direction(direction);
+        auto check_position = tube.position + direction_vector;
+        if (is_valid_grid_position(check_position) && get_grid(check_position) == 0)
+            possible_directions.append(direction);
+    }
+
+    // If tube is stuck, kill it :^(
+    if (possible_directions.is_empty()) {
+        tube.direction = Direction::None;
+        tube.active = false;
+        return;
+    }
+
+    // Remove our old direction if we have other options available
+    Direction const old_direction = tube.direction;
+    if (possible_directions.size() >= 2 && possible_directions.contains_slow(old_direction))
+        possible_directions.remove_all_matching([&old_direction](Direction const& item) { return item == old_direction; });
+
+    // Select a random new direction
+    tube.direction = possible_directions[random_int(0, static_cast<int>(possible_directions.size()) - 1)];
+
+    // Determine how far we can go in this direction
+    auto direction_vector = vector_for_direction(tube.direction);
+    int max_stretch = random_int(1, tube_travel_max_stretch);
+    IntVector3 new_target = tube.position;
+    while (max_stretch-- > 0) {
+        new_target += direction_vector;
+        if (!is_valid_grid_position(new_target) || get_grid(new_target) != 0)
+            break;
+        set_grid(new_target, 1);
+        tube.target_position = new_target;
+    }
+    tube.progress_to_target = 0.;
+}
+
+ErrorOr<void> Tubes::create_buffer(Gfx::IntSize size)
+{
+    m_bitmap = TRY(Gfx::Bitmap::try_create(Gfx::BitmapFormat::BGRx8888, size));
+    m_gl_context = GL::create_context(*m_bitmap);
+    return {};
+}
+
+u8 Tubes::get_grid(IntVector3 position)
+{
+    return m_grid[position.z() * grid_resolution * grid_resolution + position.y() * grid_resolution + position.x()];
+}
+
+bool Tubes::is_valid_grid_position(Gfx::IntVector3 position)
+{
+    return position.x() >= 0
+        && position.x() < static_cast<int>(grid_resolution)
+        && position.y() >= 0
+        && position.y() < static_cast<int>(grid_resolution)
+        && position.z() >= 0
+        && position.z() < static_cast<int>(grid_resolution);
+}
+
+void Tubes::set_grid(IntVector3 position, u8 value)
+{
+    m_grid[position.z() * grid_resolution * grid_resolution + position.y() * grid_resolution + position.x()] = value;
+}
+
+void Tubes::mousemove_event(GUI::MouseEvent& event)
+{
+    if (m_mouse_origin.is_null()) {
+        m_mouse_origin = event.position();
+    } else if (event.position().distance_from(m_mouse_origin) > mouse_max_distance_move) {
+        GUI::Application::the()->quit();
+    }
+}
+
+void Tubes::mousedown_event(GUI::MouseEvent&)
+{
+    GUI::Application::the()->quit();
+}
+
+void Tubes::keydown_event(GUI::KeyEvent&)
+{
+    GUI::Application::the()->quit();
+}
+
+void Tubes::paint_event(GUI::PaintEvent& event)
+{
+    GUI::Painter painter(*this);
+    painter.add_clip_rect(event.rect());
+    painter.blit(rect().location(), *m_bitmap, m_bitmap->rect());
+}
+
+void Tubes::reset_tubes()
+{
+    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
+
+    // Random rotation
+    glMatrixMode(GL_PROJECTION);
+    glPopMatrix();
+    glPushMatrix();
+    glRotated((random_double() - .5) * 2 * rotation_range, 0., 1., 0.);
+    glMatrixMode(GL_MODELVIEW);
+
+    // Clear grid
+    m_grid.fill_with(0);
+
+    // Create new set of tubes
+    auto free_grid_position = [&]() {
+        for (;;) {
+            IntVector3 position = {
+                random_int(0, grid_resolution - 1),
+                random_int(0, grid_resolution - 1),
+                random_int(0, grid_resolution - 1),
+            };
+            if (get_grid(position) != 0)
+                continue;
+            return position;
+        }
+    };
+    m_tubes.clear_with_capacity();
+    int tube_count = random_int(tube_minimum_count, tube_maximum_count);
+    while (tube_count-- > 0) {
+        Tube new_tube = {
+            .color = {
+                random_double(),
+                random_double(),
+                random_double(),
+            },
+            .position = free_grid_position(),
+        };
+        choose_new_direction_for_tube(new_tube);
+        m_tubes.append(new_tube);
+        set_grid(new_tube.position, 1);
+    }
+}
+
+void Tubes::setup_view()
+{
+    glClearColor(0.f, 0.f, 0.f, 1.f);
+
+    glMatrixMode(GL_PROJECTION);
+    double const zoom = .25;
+    auto const half_aspect_ratio = static_cast<double>(m_bitmap->width()) / m_bitmap->height() * zoom;
+    glFrustum(-half_aspect_ratio, half_aspect_ratio, -zoom, zoom, .5, 10.);
+    glTranslated(0., 0., -2.);
+    glPushMatrix();
+    glMatrixMode(GL_MODELVIEW);
+
+    // Set up lighting
+    glEnable(GL_LIGHTING);
+    glEnable(GL_LIGHT0);
+    GLfloat light_ambient[] { .0f, .0f, .0f, 1.f };
+    glLightfv(GL_LIGHT0, GL_AMBIENT, light_ambient);
+    GLfloat light_diffuse[] { 1.f, 1.f, 1.f, 1.f };
+    glLightfv(GL_LIGHT0, GL_DIFFUSE, light_diffuse);
+    GLfloat light_specular[] { 1.f, 1.f, 1.f, 1.f };
+    glLightfv(GL_LIGHT0, GL_SPECULAR, light_specular);
+    GLfloat light_position[] { .5f, 1.f, .5f, 0.f };
+    glLightfv(GL_LIGHT0, GL_POSITION, light_position);
+
+    GLfloat mat_specular[] { 1.f, 1.f, 1.f, 1.f };
+    glMaterialfv(GL_FRONT, GL_SPECULAR, mat_specular);
+    glMaterialf(GL_FRONT, GL_SHININESS, 8.f);
+
+    // Adapt the vertex color as ambient and diffuse colors
+    glEnable(GL_COLOR_MATERIAL);
+    glColorMaterial(GL_FRONT, GL_AMBIENT_AND_DIFFUSE);
+
+    glEnable(GL_DEPTH_TEST);
+    glDepthFunc(GL_LEQUAL);
+    glEnable(GL_NORMALIZE);
+    glShadeModel(GL_SMOOTH);
+}
+
+void Tubes::timer_event(Core::TimerEvent&)
+{
+    update_tubes();
+    m_gl_context->present();
+    repaint();
+}
+
+void Tubes::update_tubes()
+{
+    if (++m_ticks % reset_every_ticks == 0)
+        reset_tubes();
+
+    double const primitive_size = 2.; // our tubes and spheres are 1 in diameter, so object size is 2
+    double const grid_width = 2.;
+    double const grid_scale = 1. / grid_resolution;
+    double const primitive_scale = 1. / primitive_size;
+    double const tube_length_scale = tube_movement_per_tick * primitive_size;
+    double const tube_thickness_scale = tube_relative_thickness * primitive_scale;
+    for (auto& tube : m_tubes) {
+        if (!tube.active)
+            continue;
+
+        glColor3d(tube.color.x(), tube.color.y(), tube.color.z());
+        glPushMatrix();
+
+        auto pos = tube.position;
+        glTranslated(
+            pos.x() * grid_scale * grid_width - (grid_width / 2.),
+            pos.y() * grid_scale * grid_width - (grid_width / 2.),
+            pos.z() * grid_scale * grid_width - (grid_width / 2.));
+        glScaled(grid_scale, grid_scale, grid_scale);
+
+        // Draw sphere if we're at the start or a corner
+        if (tube.progress_to_target == 0.) {
+            glPushMatrix();
+            glScaled(tube_thickness_scale, tube_thickness_scale, tube_thickness_scale);
+            draw_sphere();
+            glPopMatrix();
+        }
+
+        // Draw tube at the current position
+        glPushMatrix();
+        auto direction_vector = vector_for_direction(tube.direction);
+        auto distance_to_target = (tube.target_position - tube.position).length<double>();
+        auto movement_magnitude = tube.progress_to_target * (distance_to_target - tube_movement_per_tick) / distance_to_target * grid_width;
+        glTranslated(
+            direction_vector.x() * movement_magnitude,
+            direction_vector.y() * movement_magnitude,
+            direction_vector.z() * movement_magnitude);
+        auto tube_rotation = tube_rotation_for_direction(tube.direction);
+        glRotated(tube_rotation.w(), tube_rotation.x(), tube_rotation.y(), tube_rotation.z());
+        glScaled(tube_thickness_scale, tube_thickness_scale, primitive_scale * tube_length_scale);
+
+        draw_tube();
+        glPopMatrix();
+
+        // Move towards target
+        if (tube.progress_to_target >= distance_to_target) {
+            tube.position = tube.target_position;
+            choose_new_direction_for_tube(tube);
+        } else {
+            tube.progress_to_target = min(tube.progress_to_target + tube_movement_per_tick, distance_to_target);
+        }
+
+        glPopMatrix();
+    }
+}

Userland/Demos/Tubes/Tubes.h

@@ -0,0 +1,64 @@
+/*
+ * Copyright (c) 2022, Jelle Raaijmakers <jelle@gmta.nl>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#pragma once
+
+#include <AK/FixedArray.h>
+#include <AK/Vector.h>
+#include <LibGUI/Widget.h>
+#include <LibGL/GLContext.h>
+#include <LibGfx/Vector3.h>
+
+enum class Direction : u8 {
+    None = 0,
+    XPositive = 1,
+    XNegative = 2,
+    YPositive = 3,
+    YNegative = 4,
+    ZPositive = 5,
+    ZNegative = 6,
+};
+
+struct Tube {
+    bool active { true };
+    DoubleVector3 color;
+    IntVector3 position;
+    Direction direction { Direction::None };
+    IntVector3 target_position { 0, 0, 0 };
+    double progress_to_target { 0 };
+};
+
+class Tubes final : public GUI::Widget {
+    C_OBJECT(Tubes)
+public:
+    virtual ~Tubes() override = default;
+
+    ErrorOr<void> create_buffer(Gfx::IntSize);
+    void reset_tubes();
+    void setup_view();
+    void update_tubes();
+
+private:
+    Tubes(int);
+
+    void choose_new_direction_for_tube(Tube&);
+    u8 get_grid(IntVector3);
+    bool is_valid_grid_position(IntVector3);
+    void set_grid(IntVector3, u8 value);
+
+    virtual void paint_event(GUI::PaintEvent&) override;
+    virtual void timer_event(Core::TimerEvent&) override;
+    virtual void keydown_event(GUI::KeyEvent&) override;
+    virtual void mousedown_event(GUI::MouseEvent& event) override;
+    virtual void mousemove_event(GUI::MouseEvent& event) override;
+
+    RefPtr<Gfx::Bitmap> m_bitmap;
+    FixedArray<u8> m_grid;
+    OwnPtr<GL::GLContext> m_gl_context;
+    Gfx::IntPoint m_mouse_origin;
+    u64 m_ticks { 0 };
+    Vector<Tube> m_tubes;
+};

Userland/Demos/Tubes/main.cpp

@@ -0,0 +1,55 @@
+/*
+ * Copyright (c) 2022, Jelle Raaijmakers <jelle@gmta.nl>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include <Demos/Tubes/Tubes.h>
+#include <LibCore/ArgsParser.h>
+#include <LibCore/System.h>
+#include <LibGUI/Application.h>
+#include <LibGUI/Icon.h>
+#include <LibGUI/Window.h>
+#include <LibMain/Main.h>
+
+ErrorOr<int> serenity_main(Main::Arguments arguments)
+{
+    TRY(Core::System::pledge("stdio recvfd sendfd rpath unix prot_exec"));
+
+    unsigned refresh_rate = 12;
+
+    Core::ArgsParser args_parser;
+    args_parser.set_general_help("Screensaver rendering colorful moving tubes using LibGL");
+    args_parser.add_option(refresh_rate, "Refresh rate", "rate", 'r', "milliseconds");
+    args_parser.parse(arguments);
+
+    auto app = TRY(GUI::Application::try_create(arguments));
+
+    TRY(Core::System::pledge("stdio recvfd sendfd rpath prot_exec"));
+
+    auto app_icon = GUI::Icon::default_icon("app-tubes"sv);
+    auto window = TRY(GUI::Window::try_create());
+
+    window->set_double_buffering_enabled(true);
+    window->set_title("Tubes");
+    window->set_resizable(false);
+    window->set_frameless(true);
+    window->set_fullscreen(true);
+    window->set_minimizable(false);
+    window->set_icon(app_icon.bitmap_for_size(16));
+    window->update();
+
+    auto tubes_widget = TRY(window->try_set_main_widget<Tubes>(refresh_rate));
+    tubes_widget->set_fill_with_background_color(false);
+    tubes_widget->set_override_cursor(Gfx::StandardCursor::Hidden);
+    window->show();
+
+    TRY(tubes_widget->create_buffer(window->size()));
+    tubes_widget->setup_view();
+    tubes_widget->reset_tubes();
+
+    window->move_to_front();
+    window->set_cursor(Gfx::StandardCursor::Hidden);
+
+    return app->exec();
+}