It's not obligatory to write type components at declarations; if

[gacela.git] / src / system.scm

diff --git a/src/system.scm b/src/system.scm
index 4da0b1c91bfdac2c1dd0391e828b58e98db7acdf..9df7cdcc5a701d84783f04e7157497936888513f 100644 (file)
--- a/src/system.scm
+++ b/src/system.scm
@@ -16,13 +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))))
@@ -31,23 +32,130 @@
   `(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 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 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 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 entities components)
+  (define (set-components clist new-components)
+    (cond ((null? new-components)
+          clist)
+         (else
+          (set-components
+           (if (cdar new-components)
+               (assoc-set! clist (caar new-components) (cdar new-components))
+               (assoc-remove! clist (caar new-components)))
+           (cdr new-components)))))
+  (set-entity key (set-components (alist-copy (assoc-ref entities key)) (normalize-components new-components)) entities components))
+
+(define (set-entities new-entities entities components)
+  (cond ((null? new-entities)
+        (values entities components))
+       (else
+        (cond ((not (caar new-entities))
+               (receive (e c k) (new-entity (cdar new-entities) entities components)
+                        (set-entities (cdr new-entities) e c)))
+              ((not (cdar new-entities))
+               (receive (e c) (remove-entity (caar new-entities) entities components)
+                        (set-entities (cdr new-entities) e c)))
+              (else
+               (receive (e c) (set-entity-components (caar new-entities) (cdar new-entities) entities components)
+                        (set-entities (cdr new-entities) e c)))))))
+
+   
+(export new-entity
+       remove-entity
+       set-entity
+       set-entity-components
+       set-entities)
+
+
 ;;; Making systems
 
 (define* (find-entities-by-components c t)
@@ -64,8 +172,12 @@
   (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 (get-component-type x) component-types)) (cdr x)))) e*)))
-      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)))
+         (set-entities res e c))))))
 
 
 (export find-entities-by-components