add framecounter

add framecounter to be able to slow down movement and possibly other stuff

src/actor.c

@@ -130,10 +130,12 @@ void scroll_actor(Actor *actor)
   }
 }
 
-void move_actor_with_joypad(Actor *actor)
+// Move the actor with the joypad
+void move_actor_with_joypad(Actor *actor, uint8_t framecount)
 {
   // Read buttons
   uint8_t buttons = joypad();
+  uint8_t velocity = 1;
 
   bool is_moving_x = FALSE;
   bool is_moving_y = FALSE;
@@ -145,14 +147,20 @@ void move_actor_with_joypad(Actor *actor)
   {
     actor->is_facing_right = FALSE;
     is_moving_x = TRUE;
-    actor->next_x -= 1;
+    if (framecount % 2 == 0) // move every 2nd frame keeps it smooth and without stutter
+    {
+      actor->next_x -= velocity;
+    }
     actor->dx = -1;
   }
   else if (buttons & J_RIGHT)
   {
     actor->is_facing_right = TRUE;
     is_moving_x = TRUE;
-    actor->next_x += 1;
+    if (framecount % 2 == 0)
+    {
+      actor->next_x += velocity;
+    }
     actor->dx = 1;
   }
   else
@@ -163,13 +171,19 @@ void move_actor_with_joypad(Actor *actor)
   if (buttons & J_UP)
   {
     is_moving_y = TRUE;
-    actor->next_y -= 1;
+    if (framecount % 2 == 0)
+    {
+      actor->next_y -= velocity;
+    }
     actor->dy = -1;
   }
   else if (buttons & J_DOWN)
   {
     is_moving_y = TRUE;
-    actor->next_y += 1;
+    if (framecount % 2 == 0)
+    {
+      actor->next_y += velocity;
+    }
     actor->dy = 1;
   }
   else

src/actor.h

@@ -34,6 +34,6 @@ void move_actor(Actor *actor, uint8_t x, uint8_t y);
 
 void scroll_actor(Actor *actor);
 
-void move_actor_with_joypad(Actor *actor);
+void move_actor_with_joypad(Actor *actor, uint8_t framecount);
 
 void setup_actor(Actor *actor, uint8_t sprite_id, uint8_t tile_width, uint8_t tile_height, uint8_t tilemap_start, uint8_t total_frames, bool is_facing_right, const unsigned char *tilemap, const metasprite_t *metasprite);

src/main.c

@@ -15,6 +15,7 @@
 #include "collision.h"
 
 Actor submarine;
+uint8_t framecount;
 
 uint8_t two_frame_counter = 0;
 uint8_t two_frame_real_value = 0;
@@ -22,6 +23,20 @@ uint8_t two_frame_real_value = 0;
 #define TILEMAP_WIDTH_IN_TILES (tilemap_WIDTH >> 3)
 #define TILEMAP_HEIGHT_IN_TILES (tilemap_HEIGHT >> 3)
 
+// animation counter and the directional controls update the player's location on every 2nd frame
+// from https://gbdev.gg8.se/forums/viewtopic.php?id=850
+void animcounter(uint8_t numframes)
+{
+    if (framecount == numframes)
+    {
+        framecount = 0; //"framecount" declared at top of file.
+    }
+    framecount++;
+
+    // Done processing, yield CPU and wait for start of next frame
+    vsync();
+}
+
 // generic frame counter function
 // from https://laroldsjubilantjunkyard.com/tutorial/rpg-style-movement-in-gbdk/
 void update_two_frame_counter(void)
@@ -153,14 +168,9 @@ void main(void)
         update_two_frame_counter();
         animate_actor(&submarine, two_frame_counter);
 
-        // Move the actor with the joypad
+        move_actor_with_joypad(&submarine, framecount);
-        move_actor_with_joypad(&submarine);
         // joypad_input(&submarine);
 
-        // Wait for next frame
+        animcounter(96); // I picked 96 because of how many factors it has.  Easy to have different spaced timings that don't stutter when the counter loops.
-        wait_vbl_done();
-
-        // Done processing, yield CPU and wait for start of next frame
-        vsync();
     }
 }