Initial commit

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

src/effects.h

@@ -0,0 +1,102 @@
+#pragma once
+
+#include "anm2.h"
+#include <vector>
+
+struct Game;
+
+// Describes a spray of square particles, fanned around angle by spread. Fill is how far their colour takes over their
+// black middle.
+struct Burst
+{
+    float angle = 0;
+    float fill = 0;
+    float gravity = 0;
+    float life = 0.4f;
+    float size = 3;
+    float speed = 100;
+    float spread = PI;
+    int count = 8;
+};
+
+struct Particle
+{
+    Color color;
+    Vec2 position;
+    Vec2 velocity;
+    float fill;
+    float gravity;
+    float life;
+    float lifeMax;
+    float size;
+};
+
+// Text that hops up from where it appears and fades, like damage numbers. Jitter shakes it, in pixels.
+// Damage numbers also keep their value and which target they're over, so quick hits can add up.
+struct Popup
+{
+    Color color;
+    Vec2 position;
+    Vec2 velocity;
+    char text[16];
+    float jitter;
+    float life;
+    float scale;
+    int target;
+    int value;
+};
+
+// Damage dealt at a moment in game time, for the DPS readout.
+struct Hit
+{
+    float time = 0;
+    int amount = 0;
+};
+
+// A muzzle flash: a brief white star at the barrel, pointing along the shot.
+struct Flash
+{
+    Color color;
+    Vec2 position;
+    float angle = 0;
+    float life = 0;
+    float size = 0;
+};
+
+// A fading copy of a sprite left behind by something moving fast.
+struct Afterimage
+{
+    Pose pose;
+    float life = 0;
+};
+
+// Particles, afterimages, text popups, screen shake and the damage-per-second tally. While muted (during a
+// rollback replay) it ignores new requests.
+class Effects
+{
+public:
+    bool isMuted = false;
+
+    void burst(Burst burst, Vec2 position, float angle, Color color);
+    void afterimage_spawn(Pose pose);
+    void flash_spawn(Vec2 position, float angle, float size, Color color);
+    void afterimage_draw(Game& game);
+    void number_spawn(Vec2 position, int value, int target, Color color);
+    void dps_record(int amount);
+    float dps_get();
+    void popup_spawn(Vec2 position, const char* text, Color color);
+    void shake_add(float amount);
+    Vec2 shake_get();
+    void update();
+    void draw(Game& game);
+    void clear();
+
+private:
+    std::vector<Afterimage> afterimages;
+    std::vector<Flash> flashes;
+    std::vector<Hit> hits;
+    std::vector<Particle> particles;
+    std::vector<Popup> popups;
+    float shake = 0;
+    int ticks = 0;
+};