From 8d2ba1419c060078c0aeeb33ef4e84da482b78f5 Mon Sep 17 00:00:00 2001
From: quou <quou@disroot.org>
Date: Wed, 2 Oct 2024 21:23:04 +1000
Subject: particle effects

---
 Makefile |  1 +
 effect.c | 40 ++++++++++++++++++++++++++++++++++++++++
 obj.h    | 13 +++++++++++++
 world.c  | 20 ++++++++++++++++++++
 world.h  | 12 +++++++++++-
 5 files changed, 85 insertions(+), 1 deletion(-)
 create mode 100644 effect.c

diff --git a/Makefile b/Makefile
index 06f7573..65f4b5d 100644
--- a/Makefile
+++ b/Makefile
@@ -47,6 +47,7 @@ sources = \
 	animation.c \
 	asset.c \
 	deathzone.c \
+	effect.c \
 	enemy.c \
 	hud.c \
 	map.c \
diff --git a/effect.c b/effect.c
new file mode 100644
index 0000000..9db1608
--- /dev/null
+++ b/effect.c
@@ -0,0 +1,40 @@
+#include "config.h"
+#include "maths.h"
+#include "obj.h"
+#include "random.h"
+#include "render.h"
+
+void init_effect(Effect* e, int x, int y, int vx, int vy, int c) {
+	int i;
+	e->c = c;
+	for (i = 0; i < c; i++) {
+		const int a = get_r() & 0xff;
+		const int sa = sin_table[a];
+		const int ca = cos_table[a];
+		e->x[i] = x;
+		e->y[i] = y;
+		e->vx[i] = vx + ca - sa + get_rf();
+		e->vy[i] = vy + sa + ca + get_rf();
+	}
+	e->life = 100;
+}
+
+int update_effect(Effect* e) {
+	int i;
+	for (i = 0; i < e->c; i++) {
+		e->vy[i] += main_gravity;
+		e->x[i] += e->vx[i];
+		e->y[i] += e->vy[i];
+	}
+	return !(e->life--);
+}
+
+void ren_effect(const Effect* e, Renderer* r) {
+	Rect re = { 0, 0, 1, 1 };
+	int i;
+	for (i = 0; i < e->c; i++) {
+		re.x = e->x[i] >> fbits;
+		re.y = e->y[i] >> fbits;
+		ren_rect(r, &re);
+	}
+}
diff --git a/obj.h b/obj.h
index ad7098c..f29d5a4 100644
--- a/obj.h
+++ b/obj.h
@@ -65,6 +65,19 @@ void init_particle(Particle* p, int x, int y, int anim, int bmp);
 int update_particle(Particle* p);
 void ren_particle(const Particle* p, struct Renderer* r);
 
+#define effect_max 32
+typedef struct {
+	int x[effect_max];
+	int y[effect_max];
+	int vx[effect_max];
+	int vy[effect_max];
+	int c, life;
+} Effect;
+
+void init_effect(Effect* e, int x, int y, int vx, int vy, int c);
+int update_effect(Effect* e);
+void ren_effect(const Effect* e, struct Renderer* r);
+
 typedef enum {
 	enemy_demon
 } Enemy_Type;
diff --git a/world.c b/world.c
index b1f73ec..1881df2 100644
--- a/world.c
+++ b/world.c
@@ -54,6 +54,21 @@ Deathzone* inst_deathzone(
 	return d;
 }
 
+Effect* inst_effect(
+	World* w,
+	int x,
+	int y,
+	int vx,
+	int vy,
+	int c
+) {
+	Effect* e;
+	assert(w->effect_count < max_effects);
+	e = &w->effects[w->effect_count++];
+	init_effect(e, x, y, vx, vy, c);
+	return e;
+}
+
 void update_world(World* w, const App* a) {
 	int i;
 	if (w->laser.life)
@@ -69,6 +84,9 @@ void update_world(World* w, const App* a) {
 	for (i = w->particle_count - 1; i >= 0; i--)
 		if (update_particle(&w->particles[i]))
 			w->particles[i] = w->particles[--w->particle_count];
+	for (i = w->effect_count - 1; i >= 0; i--)
+		if (update_effect(&w->effects[i]))
+			w->effects[i] = w->effects[--w->effect_count];
 	for (i = w->enemy_count - 1; i >= 0; i--)
 		if (update_enemy(&w->enemies[i], w))
 			w->enemies[i] = w->enemies[--w->enemy_count];
@@ -81,6 +99,8 @@ void ren_world(const World* w, struct Renderer* r) {
 	render_map(&w->map, r);
 	for (i = 0; i < w->particle_count; i++)
 		ren_particle(&w->particles[i], r);
+	for (i = 0; i < w->effect_count; i++)
+		ren_effect(&w->effects[i], r);
 	for (i = 0; i < w->enemy_count; i++)
 		ren_enemy(&w->enemies[i], r);
 	if (w->laser.life)
diff --git a/world.h b/world.h
index 05372ae..81feb6f 100644
--- a/world.h
+++ b/world.h
@@ -7,6 +7,7 @@
 #define max_particles 32
 #define max_enemies 16
 #define max_deathzones 16
+#define max_effects 16
 
 struct Renderer;
 
@@ -14,7 +15,8 @@ typedef struct World {
 	Particle particles[max_particles];
 	Enemy enemies[max_enemies];
 	Deathzone deathzones[max_deathzones];
-	int particle_count, enemy_count;
+	Effect effects[max_effects];
+	int particle_count, enemy_count, effect_count;
 	int deathzone_count;
 	Player player;
 	Laser laser;
@@ -45,6 +47,14 @@ Deathzone* inst_deathzone(
 	int life,
 	int friendly
 );
+Effect* inst_effect(
+	World* w,
+	int x,
+	int y,
+	int vx,
+	int vy,
+	int c
+);
 void update_world(World* w, const struct App* a);
 void ren_world(const World* w, struct Renderer* r);
 
-- 
cgit v1.2.3-54-g00ecf