diff --git a/src/context.h b/src/context.h
index b046c97..b80da22 100644
--- a/src/context.h
+++ b/src/context.h
@@ -62,6 +62,8 @@ typedef struct context {
     bool debug;
     bool is_running;
     bool resync_flag;
+
+    bool window_size_has_changed;
 } t_ctx;
 
 extern t_ctx ctx;
diff --git a/src/input.h b/src/input.h
index f514342..0b7e501 100644
--- a/src/input.h
+++ b/src/input.h
@@ -54,7 +54,6 @@ struct action_hash_item {
 
 struct input_state {
     struct action_hash_item *action_hash;
-    SDL_Renderer *renderer; /* some input relates to the screen in some way */
     const uint8_t *keyboard_state; /* array of booleans indexed by scancode */
     uint32_t mouse_state;          /* SDL mouse button bitmask */
     t_vec2 mouse_window_position;
diff --git a/src/main.c b/src/main.c
index 910c040..3e83ffa 100644
--- a/src/main.c
+++ b/src/main.c
@@ -23,6 +23,8 @@
 static void poll_events(void) {
     SDL_Event e;
 
+    ctx.window_size_has_changed = false;
+
     while (SDL_PollEvent(&e)) {
         switch (e.type) {
         case SDL_QUIT:
@@ -37,6 +39,7 @@ static void poll_events(void) {
             case SDL_WINDOWEVENT_RESIZED:
                 ctx.window_w = e.window.data1;
                 ctx.window_h = e.window.data2;
+                ctx.window_size_has_changed = true;
                 break;
             }
 
diff --git a/src/rendering.c b/src/rendering.c
index a5d34cd..f9538bf 100644
--- a/src/rendering.c
+++ b/src/rendering.c
@@ -141,26 +141,27 @@ static void render_space(void) {
 void render(void) {
     textures_update_atlas(&ctx.texture_cache);
 
-    /* TODO: only do this when needed */
     /* fit rendering context onto the resizable screen */
-    if ((float)ctx.window_w / (float)ctx.window_h > RENDER_BASE_RATIO) {
-        float ratio = (float)ctx.window_h / (float)RENDER_BASE_HEIGHT;
-        int w = (int)((float)RENDER_BASE_WIDTH * ratio);
-        glViewport(
-            ctx.window_w / 2 - w / 2,
-            0,
-            w,
-            ctx.window_h
-        );
-    } else {
-        float ratio = (float)ctx.window_w / (float)RENDER_BASE_WIDTH;
-        int h = (int)((float)RENDER_BASE_HEIGHT * ratio);
-        glViewport(
-            0,
-            ctx.window_h / 2 - h / 2,
-            ctx.window_w,
-            h
-        );
+    if (ctx.window_size_has_changed) {
+        if ((float)ctx.window_w / (float)ctx.window_h > RENDER_BASE_RATIO) {
+            float ratio = (float)ctx.window_h / (float)RENDER_BASE_HEIGHT;
+            int w = (int)((float)RENDER_BASE_WIDTH * ratio);
+            glViewport(
+                ctx.window_w / 2 - w / 2,
+                0,
+                w,
+                ctx.window_h
+            );
+        } else {
+            float ratio = (float)ctx.window_w / (float)RENDER_BASE_WIDTH;
+            int h = (int)((float)RENDER_BASE_HEIGHT * ratio);
+            glViewport(
+                0,
+                ctx.window_h / 2 - h / 2,
+                ctx.window_w,
+                h
+            );
+        }
     }
 
     glClearColor((1.0f / 255) * 230,