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-rw-r--r--2d/game-loop.scm22
1 files changed, 12 insertions, 10 deletions
diff --git a/2d/game-loop.scm b/2d/game-loop.scm
index 1a9b518..0337db0 100644
--- a/2d/game-loop.scm
+++ b/2d/game-loop.scm
@@ -62,12 +62,12 @@
(define handle-events
(let ((e (SDL:make-event)))
(lambda ()
- "Handles all events in the SDL event queue."
+ "Handle all events in the SDL event queue."
(while (SDL:poll-event e)
(handle-event e)))))
(define (handle-event e)
- "Calls the relevant callback for the event."
+ "Call the relevant callbacks for the event, E."
(case (SDL:event:type e)
((active)
(scene-trigger current-scene 'active))
@@ -119,7 +119,8 @@
(let* ((elapsed-time 0)
(fps 0))
(lambda (dt)
- "Increments. Resets to 0 every second."
+ "Increment the frames-per-second counter. Resets to 0 every
+second."
(let ((new-time (+ elapsed-time dt))
(new-fps (1+ fps)))
(if (>= new-time 1000)
@@ -132,7 +133,7 @@
(set! elapsed-time new-time)))))))
(define (current-fps)
- "Returns the current FPS value."
+ "Return the current FPS value."
game-fps)
;;;
@@ -140,7 +141,7 @@
;;;
(define (render dt)
- "Renders a frame."
+ "Render a frame."
(set-gl-matrix-mode (matrix-mode modelview))
(gl-load-identity)
(gl-clear (clear-buffer-mask color-buffer depth-buffer))
@@ -150,7 +151,7 @@
(define (update accumulator)
"Call the update callback. The update callback will be called as
-many times as tick-interval can divide accumulator. The return value
+many times as `tick-interval` can divide ACCUMULATOR. The return value
is the unused accumulator time."
(if (>= accumulator tick-interval)
(begin
@@ -231,7 +232,9 @@ the stack."
;;;
(define (game-loop last-time accumulator)
- "Runs input, render, and update hooks."
+ "Update game state, and render. LAST-TIME is the time in
+milliseconds of the last iteration of the loop. ACCUMULATOR is the
+time in milliseconds that has passed since the last game update."
(when running
(let* ((current-time (SDL:get-ticks))
(dt (- current-time last-time))
@@ -243,7 +246,7 @@ the stack."
remainder))))
(define (run-game game)
- "Open a window and start playing GAME."
+ "Open a window and start the game loop for GAME."
(open-window (game-title game)
(game-resolution game)
(game-fullscreen? game))
@@ -254,6 +257,5 @@ the stack."
(close-window))
(define (quit-game-loop!)
- "Tell the game loop to finish up the current frame and then
-terminate."
+ "Finish the current frame and terminate the game loop."
(set! running #f))