From 31270934f62a3dbaefdf717d559195016e3385d0 Mon Sep 17 00:00:00 2001
From: Javier Sancho <jsf@jsancho.org>
Date: Sun, 19 Aug 2012 21:15:50 +0200
Subject: [PATCH] Extensions for main loop (meshes, controllers, etc)

---
 src/gacela.scm | 34 +++++++++++++++++++++-------------
 src/views.scm  | 29 ++++++++++++++++++++++++-----
 2 files changed, 45 insertions(+), 18 deletions(-)

diff --git a/src/gacela.scm b/src/gacela.scm
index 70ac867..90e8581 100644
--- a/src/gacela.scm
+++ b/src/gacela.scm
@@ -118,7 +118,7 @@
 		(to-origin)
 		(refresh-active-mobs)
 		(run-mobs)
-		(draw-meshes)
+		(run-extensions)
 		(flip-screen)
 		(delay-frame))))
   (quit-video))
@@ -130,6 +130,26 @@
   loop-flag)
 
 
+;;; Extensions to main loop
+
+(define extensions '())
+
+(define (add-extension! proc pri)
+  "Add an extension with a priority to the main loop"
+  (set! extensions
+	(sort (assoc-set! extensions proc pri)
+	      (lambda (a b)
+		(< (cdr a) (cdr b))))))
+
+(define (remove-extension! proc)
+  "Remove an extension from the main loop"
+  (set! extensions
+	(assoc-remove! extensions proc)))
+
+(define (run-extensions)
+  (for-each (lambda (x) ((car x))) extensions))
+
+
 ;;; Game Properties
 
 (define *title* "Gacela")
@@ -338,18 +358,6 @@
      ,@body))
 
 
-;;; Views Factory
-
-(define default-view (make-hash-table))
-
-(define* (draw-meshes #:optional (meshes (hash-map->list (lambda (k v) v) default-view)))
-  (cond ((not (null? meshes))
-	 (catch #t
-		  (lambda () ((car meshes) 'draw))
-		  (lambda (key . args) #f))
-	 (draw-meshes (cdr meshes)))))
-
-
 (module-map (lambda (sym var)
 	      (if (not (eq? sym '%module-public-interface))
 		  (module-export! (current-module) (list sym))))
diff --git a/src/views.scm b/src/views.scm
index 9aa3006..f8e93e2 100644
--- a/src/views.scm
+++ b/src/views.scm
@@ -21,6 +21,18 @@
   #:use-module ((gacela gl) #:select (glPushMatrix glPopMatrix))
   #:use-module (ice-9 optargs))
 
+
+(define default-view (make-hash-table))
+
+(define* (draw-meshes #:optional (meshes (hash-map->list (lambda (k v) v) default-view)))
+  (cond ((not (null? meshes))
+	 (catch #t
+		  (lambda () (mesh-draw (car meshes)))
+		  (lambda (key . args) #f))
+	 (draw-meshes (cdr meshes)))))
+
+(add-extension! draw-meshes 50)
+
 (define-macro (define-view name content)
   `(begin
      (hash-set! active-views ',name (lambda () (video:glmatrix-block ,content)))
@@ -86,13 +98,20 @@
 	  "property-set!"
 	  (set! properties (assoc-set! properties prop-name value))))))))
 
-(define mesh-properties-set!
-  (let ((f (record-accessor mesh-type 'properties-set!)))
-    (lambda (mesh new-properties)
-      ((f mesh) new-properties))))
+(define (mesh-draw mesh)
+  (((record-accessor mesh-type 'draw) mesh)))
+
+(define (mesh-inner-property mesh prop-name)
+  (((record-accessor mesh-type 'inner-property) mesh) prop-name))
+
+(define (mesh-properties mesh)
+  (((record-accessor mesh-type 'properties) mesh)))
+
+(define (mesh-properties-set! mesh new-properties)
+  (((record-accessor mesh-type 'properties-set!) mesh) new-properties))
 
 (define* (show mesh #:optional (view default-view))
-  (let ((id (mesh 'inner-property 'id)))
+  (let ((id (mesh-inner-property mesh 'id)))
     (if (not (hash-ref view id))
 	(hash-set! view id mesh))))
 
-- 
2.39.2