2 files changed, 182 insertions, 0 deletions
diff --git a/src/games/pong/Pong.cpp b/src/games/pong/Pong.cpp
new file mode 100644
index 0000000..9a77f38
--- /dev/null
+++ b/src/games/pong/Pong.cpp
@@ -0,0 +1,140 @@
+#include "games/pong/Pong.hpp"
+#include "games/Game.hpp"
+#include "common/shapes.hpp"
+#include "renderer/Renderer.hpp"
+
+
+void
+Pong::Start()
+{
+    m_paddles[0].dir = NONE;
+    m_paddles[0].y = 1.5f;
+
+    m_paddles[1].dir = NONE;
+    m_paddles[1].y = 1.5f;
+
+    m_ball.circle.x = 2.0f;
+    m_ball.circle.y = 1.5f;
+    m_ball.circle.r = 0.1f;
+
+    m_ball.velocity.x = 1.0f;
+    m_ball.velocity.y = 0.0f;
+
+    m_game_status = game_resume;
+}
+
+void
+Pong::ProcessEvent(SDL_Event& event)
+{
+    switch (event.type) {
+    case SDL_EVENT_KEY_DOWN: {
+        auto key = event.key.key;
+        if (key == SDLK_ESCAPE) {
+            m_game_status = game_pause;
+        }
+        else if (key == SDLK_W) {
+            m_paddles[0].dir = UP;
+        }
+        else if (key == SDLK_S) {
+            m_paddles[0].dir = DOWN;
+        }
+        else if (key == SDLK_UP) {
+            m_paddles[1].dir = UP;
+        }
+        else if (key == SDLK_DOWN) {
+            m_paddles[1].dir = DOWN;
+        }
+    } break;
+
+    case SDL_EVENT_KEY_UP: {
+        auto key = event.key.key;
+        if (key == SDLK_W && m_paddles[0].dir == UP) {
+            m_paddles[0].dir = NONE;
+        }
+        else if (key == SDLK_S && m_paddles[0].dir == DOWN) {
+            m_paddles[0].dir = NONE;
+        }
+        else if (key == SDLK_UP && m_paddles[1].dir == UP) {
+            m_paddles[1].dir = NONE;
+        }
+        else if (key == SDLK_DOWN && m_paddles[1].dir == DOWN) {
+            m_paddles[1].dir = NONE;
+        }
+    } break;
+
+    default:;
+    }
+}
+
+void
+Pong::FinishUpdate(float dt)
+{
+    MoveBall(dt);
+    MovePaddle(m_paddles[0], dt);
+    MovePaddle(m_paddles[1], dt);
+}
+
+void
+Pong::MovePaddle(Paddle& paddle, float dt)
+{
+    if (paddle.dir) {
+        paddle.y += (float)paddle.dir * (PADDLE_SPEED * dt);
+    }
+
+    if (paddle.y <= 0.0f) {
+        paddle.y = 0.0f;
+    }
+    if (paddle.y + PADDLE_HEIGHT > 3.0f) {
+        paddle.y = 3.0f - PADDLE_HEIGHT;
+    }
+}
+
+void
+Pong::MoveBall(float dt)
+{
+    // Todo: do physics! find trajectories, find intersection, bounce off properly
+
+    m_ball.circle.x += m_ball.velocity.x * dt;
+    m_ball.circle.y += m_ball.velocity.y * dt;
+    if (m_ball.circle.x - m_ball.circle.r <= PADDLE_WIDTH) {
+        m_ball.circle.x = PADDLE_WIDTH + m_ball.circle.r;
+        m_ball.velocity.x *= -1.0f;
+        m_ball.velocity.y *= -1.0f;
+    }
+    if (m_ball.circle.x + m_ball.circle.r > 4.0f - PADDLE_WIDTH) {
+        m_ball.circle.x = 4.0f - PADDLE_WIDTH - m_ball.circle.r;
+        m_ball.velocity.x *= -1.0f;
+        m_ball.velocity.y *= -1.0f;
+    }
+}
+
+void
+Pong::Draw()
+{
+    Color paddle_color = {0.6f, 0.3f, 0.3f, 1.0f};
+    Rectangle paddle1_rect = {
+        0.0f,
+        m_paddles[0].y,
+        0.0f + PADDLE_WIDTH,
+        m_paddles[0].y + PADDLE_HEIGHT
+    };
+    Rectangle paddle2_rect = {
+        4.0f - PADDLE_WIDTH,
+        m_paddles[1].y,
+        4.0f,
+        m_paddles[1].y + PADDLE_HEIGHT
+    };
+    g_renderer.PushRectangle(paddle1_rect, paddle_color, z_layer1);
+    g_renderer.PushRectangle(paddle2_rect, paddle_color, z_layer1);
+
+    // Todo: draw a circle
+    Rectangle ball_rectangle = {
+        m_ball.circle.x - m_ball.circle.r,
+        m_ball.circle.y - m_ball.circle.r,
+        m_ball.circle.x + m_ball.circle.r,
+        m_ball.circle.y + m_ball.circle.r
+    };
+    Color ball_color = {0.3f, 0.5f, 0.3f, 1.0f};
+    g_renderer.PushRectangle(ball_rectangle, ball_color, z_layer1);
+}
+
diff --git a/src/games/pong/Pong.hpp b/src/games/pong/Pong.hpp
new file mode 100644
index 0000000..ec6145b
--- /dev/null
+++ b/src/games/pong/Pong.hpp
@@ -0,0 +1,42 @@
+#pragma once
+
+#include "games/Game.hpp"
+#include "common/shapes.hpp"
+
+
+class Pong : public Game {
+    enum PaddleDirection {
+        NONE = 0,
+        UP = 1,
+        DOWN = -1
+    };
+
+    struct Paddle {
+        float y;
+        PaddleDirection dir;
+    };
+
+    struct Ball {
+        Circle circle;
+        V2F32 velocity;
+    };
+
+    static constexpr float PADDLE_HEIGHT = 0.5f;
+    static constexpr float PADDLE_WIDTH = 0.2f;
+    static constexpr float PADDLE_SPEED = 1.0f;
+
+private:
+    void Start() override;
+    void ProcessEvent(SDL_Event& event) override;
+    void FinishUpdate(float dt) override;
+    void Draw() override;
+
+private:
+    void MovePaddle(Paddle& paddle, float dt);
+    void MoveBall(float dt);
+
+private:
+    Paddle m_paddles[2];
+    Ball m_ball;
+};
+