Allow for changing the default clear color in run-game procedure.

Add a matching flag for 'chickadee play', too.

4 files changed, 23 insertions, 3 deletions

diff --git a/chickadee.scm b/chickadee.scm
index 8dc0400..7175f50 100644
--- a/chickadee.scm
+++ b/chickadee.scm
@@ -256,6 +256,7 @@ border is disabled, otherwise it is enabled.")
                    (window-height 480)
                    window-fullscreen?
                    window-resizable?
+                   (clear-color %default-clear-color)
                    (update-hz 60)
                    (load (const #t))
                    (update (const #t))
@@ -297,7 +298,8 @@ border is disabled, otherwise it is enabled.")
                                   #:multisample? #f)))
          (gfx (make-graphics-engine (window-gl-context window)))
          (default-viewport (make-atomic-box
-                            (make-viewport 0 0 window-width window-height)))
+                            (make-viewport 0 0 window-width window-height
+                                           #:clear-color clear-color)))
          (default-projection (make-atomic-box
                               (orthographic-projection 0 window-width
                                                        window-height 0
diff --git a/chickadee/cli/play.scm b/chickadee/cli/play.scm
index db2c0d6..f7c03b5 100644
--- a/chickadee/cli/play.scm
+++ b/chickadee/cli/play.scm
@@ -21,6 +21,8 @@
   #:use-module (chickadee async-repl)
   #:use-module (chickadee cli)
   #:use-module (chickadee config)
+  #:use-module (chickadee graphics color)
+  #:use-module (chickadee graphics viewport)
   #:use-module (ice-9 exceptions)
   #:use-module (ice-9 format)
   #:use-module (ice-9 match)
@@ -53,6 +55,8 @@ Play the game defined in FILE.~%")
   (display "
   -u, --update-hz=N      set update rate to N times per second")
   (display "
+  -c, --clear-color=RGB  set the clear color to hex color code RGB")
+  (display "
  --repl                  start REPL in this terminal")
   (display "
  --repl-server=[PORT]    start REPL server on PORT or 37146 by default")
@@ -85,6 +89,9 @@ Play the game defined in FILE.~%")
         (option '(#\u "update-hz") #t #f
                 (lambda (opt name arg result)
                   (alist-cons 'update-hz (string->number arg) result)))
+        (option '(#\c "clear-color") #t #f
+                (lambda (opt name arg result)
+                  (alist-cons 'clear-color (string->color arg) result)))
         (option '("repl") #f #f
                 (lambda (opt name arg result)
                   (alist-cons 'repl #t result)))
@@ -103,12 +110,13 @@ Play the game defined in FILE.~%")
                   (alist-cons 'extension arg result)))))
 
 (define %default-options
-  '((title . "chickadee")
+  `((title . "chickadee")
     (width . 640)
     (height . 480)
     (fullscreen? . #f)
     (resizable? . #f)
     (update-hz . 60)
+    (clear-color . ,%default-clear-color)
     (repl . #f)
     (language . scheme)))
 
@@ -244,6 +252,7 @@ Resume the game loop without entering a debugger."
               #:window-fullscreen? (assq-ref opts 'fullscreen?)
               #:window-resizable? (assq-ref opts 'resizable?)
               #:update-hz (assq-ref opts 'update-hz)
+              #:clear-color (assq-ref opts 'clear-color)
               #:load load-game
               #:update (let ((update* (trampoline update dt)))
                          (lambda (dt)
diff --git a/doc/api.texi b/doc/api.texi
index 9d743b4..92d18dc 100644
--- a/doc/api.texi
+++ b/doc/api.texi
@@ -41,6 +41,7 @@ calling @code{run-game} is already taken care of for you.
        [#:window-fullscreen? @code{#f}] @
        [#:window-resizable? @code{#f}] @
        [#:update-hz 60] @
+       [#:clear-color] @
        [#:load] [#:update] [#:draw] [#:quit] @
        [#:key-press] [#:key-release] [#:text-input] @
        [#:mouse-press] [#:mouse-release] [#:mouse-move] @
@@ -53,7 +54,8 @@ A new graphical window will be opened with @var{window-width} x
 @var{window-height} as its dimensions, @var{window-title} as its
 title, and in fullscreen mode if @var{window-fullscreen?} is
 @code{#t}.  If @var{window-resizable?} is @code{#t} then the window
-can be resized by the user.
+can be resized by the user.  The screen color will be set to
+@var{clear-color}, or a pleasant light blue, by default.
 
 @itemize
 @item
diff --git a/doc/chickadee.texi b/doc/chickadee.texi
index c6b2f07..a87a346 100644
--- a/doc/chickadee.texi
+++ b/doc/chickadee.texi
@@ -261,6 +261,13 @@ Make window resizable.
 
 Update the game @var{n} times per second.
 
+@item --clear-color=@var{color}
+@itemx -c @var{color}
+
+Set the screen clear color to @var{color}, a hex code in the format
+@code{#RRGGBB}.  For example, to set the clear color to black, pass
+@code{--clear-color=#000000}.
+
 @item --repl
 
 Launch a REPL in the terminal.  This will allow the game environment