From 2a08d93dcd9a52442e59c185ac85d4344e716650 Mon Sep 17 00:00:00 2001
From: Javier Sancho <jsf@jsancho.org>
Date: Mon, 17 Oct 2016 18:09:08 +0200
Subject: [PATCH] Images in development

---
 examples/fran.scm |  6 +++---
 gacela/image.scm  | 18 +++++++++++-------
 gacela/scene.scm  |  4 ++--
 3 files changed, 16 insertions(+), 12 deletions(-)

diff --git a/examples/fran.scm b/examples/fran.scm
index 9b18db8..964bbbc 100644
--- a/examples/fran.scm
+++ b/examples/fran.scm
@@ -22,9 +22,9 @@
 
 ;;; Reactive positions
 
-(define (waggle) (cos (* pi (current-time))))
-(define (wiggle) (sin (* pi (current-time))))
-
+(define (tick) (* 3000000 (get-internal-real-time)))
+(define (waggle) (* 200 (+ 1 (cos (* pi (tick))))))
+(define (wiggle) (* 300 (+ 1 (sin (* pi (tick))))))
 
 ;;; First example
 
diff --git a/gacela/image.scm b/gacela/image.scm
index 1fdeaf6..370bbd1 100644
--- a/gacela/image.scm
+++ b/gacela/image.scm
@@ -18,28 +18,32 @@
 (define-module (gacela image)
   #:use-module (gacela scene)
   #:use-module (gacela game)
+  #:use-module ((sdl2) #:prefix sdl2:)
   #:use-module ((sdl2 image) #:prefix sdl2:)
   #:use-module ((sdl2 render) #:prefix sdl2:)
+  #:use-module ((sdl2 surface) #:prefix sdl2:)
   #:export (import-bitmap
 	    move-xy))
 
-(define-syntax-rule (import-bitmap filename)
+(define (import-bitmap filename)
   (make-scene
    "bitmap"
    (let ((image (sdl2:load-image filename))
 	 (texture #f))
      (let ((a 0))
-       (lambda ()
+       (lambda* (#:key (xy '(0 0)))
 	 (if (not texture)
 	     (set! texture (sdl2:surface->texture %sdl-renderer image)))
-	 ;; (set! a (+ a 1))
-	 ;; (format #t "~a steps with texture ~a~%" a texture))))))
 	 (sdl2:clear-renderer %sdl-renderer)
-	 (sdl2:render-copy %sdl-renderer texture)
+	 (sdl2:render-copy %sdl-renderer texture #:dest-rect (sdl2:make-rect (car xy) (cadr xy) (sdl2:surface-width image) (sdl2:surface-height image)))
 	 (sdl2:present-renderer %sdl-renderer))))))
 
-(define-syntax-rule (move-xy x y scene)
+(define (move-xy x y scene)
+  (define (to-integer n)
+    (inexact->exact (round n)))
   (make-scene
    "move-xy"
    (lambda ()
-     (display-scene scene))))
+     (let ((xy (list (to-integer (if (procedure? x) (x) x))
+		     (to-integer (if (procedure? y) (y) y)))))
+       (display-scene scene #:xy xy)))))
diff --git a/gacela/scene.scm b/gacela/scene.scm
index 62b1a1e..e620480 100644
--- a/gacela/scene.scm
+++ b/gacela/scene.scm
@@ -39,8 +39,8 @@
 
 ;;; Scene Procedures
 
-(define (display-scene scene)
-  ((scene-procedure scene)))
+(define (display-scene scene . args)
+  (apply (scene-procedure scene) args))
 
 (define (run-scene scene)
   (play-game
-- 
2.39.5