Add spiral bullet

2 files changed, 82 insertions, 0 deletions

diff --git a/Spiral.cpp b/Spiral.cpp
new file mode 100644
index 0000000..636a6b2
--- /dev/null
+++ b/Spiral.cpp
@@ -0,0 +1,50 @@
+#include "Spiral.h"
+
+#include <raylib.h>
+#include <cmath>
+
+
+SpiralSystem::SpiralSystem()
+{
+    m_bullets.reserve(RESERVED);
+}
+
+
+void
+SpiralSystem::update(const float dt)
+{
+    const int min_height = 0 - 3 * MARGIN;
+    const int max_height = GetScreenHeight() + MARGIN;
+    const int min_width = 0 - MARGIN;
+    const int max_width = GetScreenWidth() + MARGIN;
+    auto it = m_bullets.begin();
+    while (it != m_bullets.end()) {
+        auto& bullet = *it;
+        bullet.timer += dt;
+        if (bullet.timer > bullet.redirect_time) {
+            bullet.timer -= bullet.redirect_time;
+            bullet.angle = bullet.angle + bullet.redirect;
+            if (bullet.angle > 2.0)
+                bullet.angle -= 2.0;
+            bullet.redirect *= bullet.redirect_decrease;
+        }
+        float velovity_x = std::cos(angle * M_PI);
+        float velovity_y = std::sin(angle * M_PI);
+        bullet.position.x += velocity_x * dt;
+        bullet.position.y += velocity_y * dt;
+        const bool y_exceeded = bullet.position.y < min_height || bullet.position.y > max_height;
+        const bool x_exceeded = bullet.position.x < min_width || bullet.position.x > max_width;
+        if (y_exceeded || x_exceeded)
+            it = m_bullets.erase(it);
+        else
+            ++it;
+    }
+}
+
+
+void
+SpiralSystem::draw()
+{
+    for (const auto& bullet : m_bullets)
+        DrawCircle(bullet.position.x, bullet.position.y, bullet.radius, bullet.color);
+}
diff --git a/Spiral.h b/Spiral.h
new file mode 100644
index 0000000..064e3a7
--- /dev/null
+++ b/Spiral.h
@@ -0,0 +1,32 @@
+#pragma once
+
+#include <vector>
+
+#include <raylib.h>
+
+
+struct SpiralBullet
+{
+    using Vector = std::vector<SpiralBullet>;
+    Vector2 position;
+    float velocity;
+    float angle;
+    float redirect;
+    float timer;
+    float redirect_time;
+    float redirect_decrease;
+    float radius;
+    Color color;
+};
+
+
+struct SpiralSystem
+{
+    static constexpr float MARGIN {40};
+    static constexpr int RESERVED {10000};
+
+    SpiralSystem();
+    void update(float dt);
+    void draw();
+    SpiralBullet::Vector m_bullets;
+};