From a0d8da27762feed02c9714e42c196a8dc7b4fb12 Mon Sep 17 00:00:00 2001
From: tijani <tijani@tijanilawal.com>
Date: Sun, 1 Sep 2024 14:28:07 -0500
Subject: [PATCH] Constant Delta Time set to 60 FPS

---
 src/ragar/ragar_main.c | 10 +++++++++-
 src/renderer/display.h |  3 +++
 2 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/src/ragar/ragar_main.c b/src/ragar/ragar_main.c
index 59a6af7..3c8ef64 100644
--- a/src/ragar/ragar_main.c
+++ b/src/ragar/ragar_main.c
@@ -15,7 +15,8 @@ Vec2F32 g_projected_points[POINTS];
 Vec3F32 camera_position = {.x = 0, .y = 0, .z = -5};
 Vec3F32 cube_rotation = {.x = 0, .y = 0, .z = 0};
 
-int is_running;
+s32 is_running;
+s32 previous_frame_time = 0;
 
 // Perspective Projection (perspective divide)
 // Formula
@@ -69,6 +70,13 @@ void process_input(void) {
 }
 
 void update(void) {
+  //  while(!SDL_TICKS_PASSED(SDL_GetTicks(), previous_frame_time + FRAME_TARGET_TIME)); // NOTE(tijani): SLOWWWW!!!!
+  s32 time_to_wait = FRAME_TARGET_TIME - (SDL_GetTicks() - previous_frame_time);
+  if (time_to_wait > 0 && time_to_wait <= FRAME_TARGET_TIME) {
+    SDL_Delay(time_to_wait);
+  }
+  //  previous_frame_time = SDL_GetTicks(); // NOTE(tijani): SLOWWW!!! because it locks the OS into this.
+
   cube_rotation.x += 0.01;
   cube_rotation.y += 0.01;
   cube_rotation.z += 0.01;
diff --git a/src/renderer/display.h b/src/renderer/display.h
index bef3d8b..251df6d 100644
--- a/src/renderer/display.h
+++ b/src/renderer/display.h
@@ -3,6 +3,9 @@
 
 #include <SDL.h>
 
+#define FPS 60
+#define FRAME_TARGET_TIME (1000 / FPS)
+
 SDL_Window *window = NULL;
 SDL_Renderer *renderer = NULL;
 SDL_Texture *colour_buffer_texture = NULL;