speed control: frame skipping to decouple terminal draw from emulation

Emulation always runs at native rate (correct game speed); --frameskip N draws
only 1 of every N+1 frames so a slow terminal no longer bottlenecks the loop.
Adds --fps cap, --uncapped/--turbo, live [ ] and f keys, HUD readout, and an
exit summary of emulated-vs-drawn fps. Replaces the confusing --render-fps.

1 files changed, 6 insertions, 0 deletions

diff --git a/src/render.h b/src/render.h
index 27da080..3b6c7e4 100644
--- a/src/render.h
+++ b/src/render.h
@@ -7,6 +7,7 @@ void term_init(void);
 void term_restore(void);
 void render_frame(GB *gb);
 void render_force_full(void);   // force a complete repaint next frame
+void render_set_hud(int frameskip, bool turbo);  // update HUD readout
 // Poll keyboard + control FIFO, update gb->buttons. False if quit requested.
 bool input_poll(GB *gb);
 
@@ -15,4 +16,9 @@ bool input_poll(GB *gb);
 void input_open_fifo(const char *path);
 void input_close_fifo(void);
 
+// Returns true once for each pending fast-forward (turbo) toggle keypress.
+bool input_take_turbo(void);
+// Net frameskip adjustment requested via '[' / ']' since last call.
+int  input_take_frameskip_delta(void);
+
 #endif