1 files changed, 39 insertions, 31 deletions

diff --git a/src/screen.c b/src/screen.c
index 5e84038..86d829d 100644
--- a/src/screen.c
+++ b/src/screen.c
@@ -5,10 +5,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
-#include <time.h>
 #include <pthread.h>
-#include <unistd.h>
-#include <signal.h>
 
 #define XLIB_ILLEGAL_ACCESS
 #include <X11/X.h>
@@ -33,6 +30,8 @@ typedef struct {
     XImage** images;
     pthread_t update_thread;
     pthread_mutex_t recreate_lock;
+    pthread_mutex_t lock;
+    uint16_t update_rate;
 } WindowState;
 
 static void init_x() {
@@ -173,7 +172,6 @@ void swapchain_next(Swapchain* swapchain) {
         next += 1;
         next %= 3;
     }
-
     swapchain->image_current = next;
     pthread_mutex_unlock(&swapchain->lock);
 }
@@ -184,28 +182,54 @@ void swapchain_submit(Swapchain* swapchain) {
     pthread_mutex_unlock(&swapchain->lock);
 }
 
+static long get_time() {
+    struct timespec spec;
+    clock_gettime(CLOCK_MONOTONIC, &spec);
+    return round(spec.tv_nsec / 1.0e6) + spec.tv_sec * 1000;
+}
+
+static void update_delta(float* delta, long* last) {
+    long now = get_time();
+    if (*last == 0) {
+        *delta = 0;
+    } else {
+        *delta = (now - *last) / 1000.0;
+    }
+    *last = now;
+}
+
 static void* swapchain_thread(void* arg) {
     struct Screen* screen = (struct Screen*) arg;
     WindowState* state = (WindowState*) screen->internal;
 
+    long last = get_time();
+    float delta;
+
     while (1) {
 
         if (screen->swapchain.images == NULL) {
             return NULL;
         }
+
+        long now = last;
+        update_delta(&delta, &now);
+        if (delta < 1.0 / state->update_rate) {
+            continue;
+        } else {
+            last = now;
+        }
         
         pthread_mutex_lock(&state->recreate_lock);
 
         pthread_mutex_lock(&screen->swapchain.lock);
-        int index = screen->swapchain.image_recent;
-        screen->swapchain.image_front = index;
+        screen->swapchain.image_front = screen->swapchain.image_recent;
         pthread_mutex_unlock(&screen->swapchain.lock);
         
         XPutImage(
             dpy,
             state->window,
             state->graphics_ctx,
-            state->images[index],
+            state->images[screen->swapchain.image_front],
             0, 0, 0, 0,
             screen->swapchain.width,
             screen->swapchain.height
@@ -213,8 +237,6 @@ static void* swapchain_thread(void* arg) {
         XSync(dpy, 0);
         
         pthread_mutex_unlock(&state->recreate_lock);
-
-        usleep(1000 * 1000 / 60);
     }
 
     return NULL;
@@ -222,7 +244,7 @@ static void* swapchain_thread(void* arg) {
 
 #define FRAMES 3
 
-void init_screen(struct Screen* screen, uint16_t width, uint16_t height, const char* title) {
+void init_screen(struct Screen* screen, uint16_t width, uint16_t height, const char* title, uint16_t update_rate) {
 
     if (dpy == NULL) {
         init_x();
@@ -233,6 +255,7 @@ void init_screen(struct Screen* screen, uint16_t width, uint16_t height, const c
 
     WindowState* state = malloc(sizeof(WindowState));
     state->window = window;
+    state->update_rate = update_rate;
 
     screen->swapchain = create_swapchain(width, height, FRAMES, bit_depth, state);
     pthread_create(&state->update_thread, NULL, &swapchain_thread, screen);
@@ -242,23 +265,6 @@ void init_screen(struct Screen* screen, uint16_t width, uint16_t height, const c
     count++;
 }
 
-static long get_time() {
-    struct timespec spec;
-    clock_gettime(CLOCK_MONOTONIC, &spec);
-    return round(spec.tv_nsec / 1.0e6) + spec.tv_sec * 1000;
-}
-
-static long last = 0;
-
-static void update_delta(struct Screen* screen) {
-    long now = get_time();
-    if (last == 0) {
-        screen->delta = 0;
-    } else {
-        screen->delta = (now - last) / 1000.0;
-    }
-    last = now;
-}
 
 static void handle_event(struct Screen* screen) {
     XEvent event;
@@ -291,11 +297,11 @@ static void handle_event(struct Screen* screen) {
 }
 
 bool poll_screen(struct Screen* screen) {
-    
     while (XPending(dpy))
         handle_event(screen);
 
-    update_delta(screen);
+    static long last = 0;
+    update_delta(&screen->delta, &last);
     return true;
 }
 
@@ -320,13 +326,15 @@ void free_screen(struct Screen* screen) {
     }
 }
 
-bool key_pressed(int keycode) {
+bool key_pressed(int code) {
+    int keycode = code - dpy->min_keycode;
     if (key_checked[keycode]) return false;
     if (!key_state[keycode]) return false;
     key_checked[keycode] = true;
     return true;
 }
 
-bool key_down(int keycode) {
+bool key_down(int code) {
+    int keycode = code - dpy->min_keycode;
     return key_state[keycode];
 }