X-Git-Url: https://git.jsancho.org/?p=gacela.git;a=blobdiff_plain;f=src%2Fsystem.scm;h=502ccd60beca405ef8a8d19908fcadb37d0f42df;hp=b4f48708201e35c6ecbb39ffca74c98013a21331;hb=9b261e3a07d92edf68979b46f756413a0ac9247a;hpb=08ad446e3685f481d5c6225ff294e18eb305cedf

diff --git a/src/system.scm b/src/system.scm
index b4f4870..502ccd6 100644
--- a/src/system.scm
+++ b/src/system.scm
@@ -16,12 +16,14 @@
 
 
 (define-module (gacela system)
+  #:use-module (ice-9 receive)
+  #:use-module (srfi srfi-1)
   #:use-module (srfi srfi-9))
 
 
 ;;; Component definitions
 
-(define (make-symbol . args)
+(define (symbol-concatenate . args)
   (string->symbol
    (string-concatenate
     (map (lambda (a) (if (symbol? a) (symbol->string a) a)) args))))
@@ -30,18 +32,188 @@
   `(begin
      (use-modules (srfi srfi-9) (srfi srfi-9 gnu))
      (define-record-type ,name
-       (,(make-symbol "make-" name) ,@args)
-       ,(make-symbol name "?")
-       ,@(map (lambda (a) (list a (make-symbol name "-" a) (make-symbol "set-" name "-" a "!"))) args))
+       (,(symbol-concatenate "make-" name) ,@args)
+       ,(symbol-concatenate name "?")
+       ,@(map (lambda (a) (list a (symbol-concatenate name "-" a) (symbol-concatenate "set-" name "-" a "!"))) args))
      (set-record-type-printer! ,name
        (lambda (record port)
 	 (format port "#<[~a]" ',name)
-	 ,@(map (lambda (a) `(format port " ~a: ~a" ',a (,(make-symbol name "-" a) record))) args)
+	 ,@(map (lambda (a) `(format port " ~a: ~a" ',a (,(symbol-concatenate name "-" a) record))) args)
 	 (format port ">")))
      ',name))
 
+(define (export-component component)
+  (let ((name (record-type-name component))
+	(m (current-module)))
+    (module-export! m (list
+		       (symbol-concatenate "make-" name)
+		       (symbol-concatenate name "?")))
+    (for-each
+     (lambda (a)
+       (module-export! (current-module)
+		       (list
+			(symbol-concatenate name "-" a)
+			(symbol-concatenate "set-" name "-" a "!"))))
+     (record-type-fields component))))
+
 (define (get-component-type component)
   (record-type-name (record-type-descriptor component)))
 
 (export define-component
+	export-component
 	get-component-type)
+
+
+;;; Entities and components
+
+(define (normalize-components components)
+  (map
+   (lambda (c)
+     (if (record? c)
+	 `(,(get-component-type c) . ,c)
+	 c))
+   components))
+
+(define (register-components entity components clist)
+  (cond ((null? components) clist)
+	(else
+	 (let* ((type (car components))
+		(elist (assoc-ref clist type)))
+	   (register-components entity (cdr components)
+	     (assoc-set! clist type
+	       (cond (elist
+		      (lset-adjoin eq? elist entity))
+		     (else
+		      (list entity)))))))))
+
+(define (unregister-components entity components clist)
+  (cond ((null? components) clist)
+	(else
+	 (let* ((type (car components))
+		(elist (lset-difference eq? (assoc-ref clist type) (list entity))))
+	   (unregister-components entity (cdr components)
+	     (cond ((null? elist)
+		    (assoc-remove! clist type))
+		   (else
+		    (assoc-set! clist type elist))))))))
+
+(define (new-entity . new-components)
+  (lambda (entities components)
+    (let ((key (gensym))
+	  (nc (normalize-components new-components)))
+      (values
+       (acons key nc entities)
+       (register-components key
+			    (map (lambda (c) (car c)) nc)
+			    components)
+       key))))
+
+(define (remove-entity key)
+  (lambda (entities components)
+    (let ((clist (map (lambda (c) (car c)) (assoc-ref entities key))))
+      (values
+       (assoc-remove! entities key)
+       (unregister-components key clist components)))))
+
+(define (set-entity key . new-components)
+  (lambda (entities components)
+    (let* ((nc (normalize-components new-components))
+	   (clist (map (lambda (c) (car c)) (assoc-ref entities key)))
+	   (nclist (map (lambda (c) (car c)) nc)))
+      (values
+       (assoc-set! entities key nc)
+       (register-components key (lset-difference eq? nclist clist)
+			    (unregister-components key (lset-difference eq? clist nclist) components))))))
+
+(define (set-entity-components key . new-components)
+  (lambda (entities components)
+    (let ((nc (normalize-components new-components))
+	  (clist (alist-copy (assoc-ref entities key))))
+      (for-each
+       (lambda (c)
+	 (assoc-set! clist (car c) (cdr c)))
+       nc)
+      (values
+       (assoc-set! entities key clist)
+       (register-components key (map (lambda (c) (car c)) nc) components)))))
+
+(define (remove-entity-components key . old-components)
+  (lambda (entities components)
+    (let ((clist (alist-copy (assoc-ref entities key))))
+      (for-each
+       (lambda (c)
+	 (assoc-remove! clist c))
+       old-components)
+      (values
+       (assoc-set! entities key clist)
+       (unregister-components key old-components components)))))
+
+(define (modify-entities changes entities components)
+  (cond ((null? changes)
+	 (values entities components))
+	(else
+	 (receive (e c) ((car changes) entities components)
+	   (modify-entities (cdr changes) e c)))))
+
+(export new-entity
+	remove-entity
+	set-entity
+	set-entity-components
+	remove-entity-components
+	modify-entities)
+
+
+;;; Making systems
+
+(define* (find-entities-by-components c t)
+  (cond ((null? t) '())
+	(else
+	 (let* ((e (assoc-ref c (car t)))
+		(e* (if e e '())))
+	   (cond ((null? (cdr t)) e*)
+		 (else
+		  (lset-intersection eq? e* (find-entities-by-components c (cdr t)))))))))
+		  
+
+(define (make-system component-types system-fun)
+  (lambda (entities components)
+    (let* ((e (find-entities-by-components components component-types))
+	   (e* (map (lambda (x) (assoc x entities)) e))
+	   (e** (map (lambda (x) (cons (car x) (filter (lambda (x) (memq (car x) component-types)) (cdr x)))) e*))
+	   (res (system-fun e**)))
+      (lambda* (#:optional (entities2 #f) (components2 #f))
+	(let ((e (if (and entities2 components2) entities2 entities))
+	      (c (if (and entities2 components2) components2 components)))
+	  (modify-entities res e c))))))
+
+
+(define (join-systems . systems)
+  (lambda (entities components)
+    (let run ((s systems) (e entities) (c components))
+      (cond ((null? s)
+	     (values e c))
+	    (else
+	     (receive (e2 c2) (((car s) e c))
+	       (run (cdr s) e2 c2)))))))
+
+
+(define (threaded-systems . systems)
+  (lambda (entities components)
+    (let run-wait ((thd
+		    (map
+		     (lambda (s)
+		       (call-with-new-thread
+			(lambda () (s entities components))))
+		     systems))
+		   (e entities) (c components))
+      (cond ((null? thd)
+	     (values e c))
+	    (else
+	     (receive (e2 c2) ((join-thread (car thd)) e c)
+	       (run-wait (cdr thd) e2 c2)))))))
+
+
+(export find-entities-by-components
+	make-system
+	join-systems
+	threaded-systems)