From 91dedb6587f3e14206f3c62e11bb0d011fc8de24 Mon Sep 17 00:00:00 2001
From: Lukas Krickl <lukas@krickl.dev>
Date: Thu, 26 Feb 2026 12:26:58 +0100
Subject: [PATCH] update: Added tick timing handler

---
 src/lrts.c      | 15 +++++++++++++--
 src/lrts_impl.h |  1 +
 src/r_render.c  |  5 ++++-
 src/t_update.c  | 38 ++++++++++++++++++++++++++++++++++++++
 src/t_update.h  | 17 +++++++++++++++++
 src/u_defs.h    |  6 ++++++
 6 files changed, 79 insertions(+), 3 deletions(-)
 create mode 100644 src/t_update.c
 create mode 100644 src/t_update.h

diff --git a/src/lrts.c b/src/lrts.c
index 110ed9d..30caf04 100644
--- a/src/lrts.c
+++ b/src/lrts.c
@@ -6,14 +6,20 @@
 #include "i_input.h"
 #include "t_camera.h"
 #include "t_map.h"
+#include "t_update.h"
 #include "u_time.h"
 
 struct lrts_config lrts_global_cfg;
+struct lrts_state lrts_global_state;
 
 struct lrts_config* lrts_cfg() {
 	return &lrts_global_cfg;
 }
 
+struct lrts_state* lrts_state() {
+	return &lrts_global_state;
+}
+
 void lrts_help(int argc, char **argv) {
 	LRTS_UNUSED(argc);
 
@@ -66,7 +72,8 @@ struct u_vec2 lrts_get_screen_res(void) {
 }
 
 void lrts_init(void) {
-	struct lrts_config* cfg = lrts_cfg();
+	struct lrts_config *cfg = lrts_cfg();
+	struct lrts_state *state = lrts_state();
 	struct u_vec2 res = lrts_get_render_res();
 
 
@@ -77,10 +84,13 @@ void lrts_init(void) {
 	i_input_init();
 	
 	u_fps_timer = u_timer_init();
-
+	t_sim_init();
 
 	t_main_camera = t_camera_init(res.x, res.y);
 	t_map = t_map_init();
+
+	state->frame_count = 0;
+	state->tick_count = 0;
 }
 
 int lrts_main(int argc, char **argv) {
@@ -94,6 +104,7 @@ int lrts_main(int argc, char **argv) {
 
 	while (!lrts_cfg()->exit) {
 		p_poll_events();
+		t_sim_update();
 		r_render_frame();
 	}
 
diff --git a/src/lrts_impl.h b/src/lrts_impl.h
index 49f7fd0..b9815a6 100644
--- a/src/lrts_impl.h
+++ b/src/lrts_impl.h
@@ -50,6 +50,7 @@
 #include "r_assets.c"
 #include "i_input.c"
 #include "u_time.c"
+#include "t_update.c"
 
 #endif
 
diff --git a/src/r_render.c b/src/r_render.c
index 837ff10..8585a29 100644
--- a/src/r_render.c
+++ b/src/r_render.c
@@ -26,15 +26,18 @@ void r_draw_pixel(struct r_framebuffer *fb, i32 x, i32 y, r_color color) {
 }
 
 void r_render_frame() {
+	struct lrts_state *state = lrts_state();
+
 	u_timer_start(&u_fps_timer);
 	p_draw_begin();
 	
 
-	t_map_draw(&t_map);
+	/* t_map_draw(&t_map); */
 
 	p_draw_end();
 	p_draw_present();
 	u_timer_end(&u_fps_timer);
 
+	state->frame_count++;
 	u_cap_fps();
 }
diff --git a/src/t_update.c b/src/t_update.c
new file mode 100644
index 0000000..472fa5d
--- /dev/null
+++ b/src/t_update.c
@@ -0,0 +1,38 @@
+#include "t_update.h"
+
+struct u_timer t_sim_timer;
+u32 t_updates_this_interval;
+
+void t_sim_init(void) {
+	t_sim_timer = u_timer_init();
+	t_updates_this_interval = 0;
+	u_timer_start(&t_sim_timer);
+}
+
+/* returns how much time should pass between each tick
+ * based on the platform time information provided */
+u32 t_sim_tick_interval(void) {
+	return (u32)p_ticks_per_second() / LRTS_TPS;
+}
+
+
+void t_sim_update(void) {
+	struct lrts_state *state = lrts_state();
+
+	/* if timer has been running for more than a second 
+	 * reset tick this sec and timer */
+	if (u_timer_end(&t_sim_timer) >= (u32)t_sim_tick_interval()) {
+		t_updates_this_interval = 0;
+		u_timer_start(&t_sim_timer);
+	}
+
+	/* bail if timer is not ready yet */
+	if (t_updates_this_interval) {
+		return;
+	}
+
+	t_updates_this_interval++;
+	state->tick_count++;
+	
+	/* update game simulation */
+}
diff --git a/src/t_update.h b/src/t_update.h
new file mode 100644
index 0000000..6c797a1
--- /dev/null
+++ b/src/t_update.h
@@ -0,0 +1,17 @@
+#ifndef T_UPDATE_H__
+#define T_UPDATE_H__
+
+#include "u_time.h"
+
+extern struct u_timer t_sim_timer;
+
+void t_sim_init(void);
+
+/**
+ * Advances the simulation by a tick
+ * Simulation updates are capped at the 
+ * max tick rate per second.
+ */ 
+void t_sim_update(void);
+
+#endif
diff --git a/src/u_defs.h b/src/u_defs.h
index f9dde6b..4d5b129 100644
--- a/src/u_defs.h
+++ b/src/u_defs.h
@@ -56,8 +56,14 @@ struct lrts_config {
 	int argc;
 };
 
+struct lrts_state {
+	u32 frame_count;
+	u32 tick_count;
+};
+
 
 struct lrts_config* lrts_cfg();
+struct lrts_state* lrts_state();
 void lrts_help(int argc, char **argv);
 void lrts_version(void);
 void lrts_getopt(int argc, char **argv, struct lrts_config *cfg);
-- 
2.30.2