Engine Access Protocol Interface

[gacela.git] / src / system.scm

diff --git a/src/system.scm b/src/system.scm
index 502ccd60beca405ef8a8d19908fcadb37d0f42df..3d5cb2b9ea482eaaaf65a81946e337d693cd94bb 100644 (file)
--- a/src/system.scm
+++ b/src/system.scm
@@ -18,7 +18,8 @@
 (define-module (gacela system)
   #:use-module (ice-9 receive)
   #:use-module (srfi srfi-1)
-  #:use-module (srfi srfi-9))
+  #:use-module (srfi srfi-9)
+  #:use-module (srfi srfi-9 gnu))
 
 
 ;;; Component definitions
@@ -28,19 +29,35 @@
    (string-concatenate
     (map (lambda (a) (if (symbol? a) (symbol->string a) a)) args))))
 
-(define-macro (define-component name . args)
-  `(begin
-     (use-modules (srfi srfi-9) (srfi srfi-9 gnu))
-     (define-record-type ,name
-       (,(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 (,(symbol-concatenate name "-" a) record))) args)
-        (format port ">")))
-     ',name))
+(define-syntax define-component
+  (lambda (x)
+    (define (concat . args)
+      (datum->syntax x
+        (apply symbol-concatenate
+         (map (lambda (a)
+                (if (string? a)
+                    a
+                    (syntax->datum a)))
+              args))))
+    (syntax-case x ()
+      ((_ name field ...)
+       (with-syntax ((make-name (concat "make-" #'name))
+                    (name? (concat #'name "?"))
+                    ((field-getter ...) (map (lambda (f) (concat #'name "-" f)) #'(field ...)))
+                    ((field-setter ...) (map (lambda (f) (concat "set-" #'name "-" f "!")) #'(field ...))))
+         #'(begin
+            (define-record-type name
+              (make-name field ...)
+              name?
+              (field field-getter field-setter)
+              ...)
+            (set-record-type-printer! name
+              (lambda (record port)
+                (format port "#<[~a]" 'name)
+                (format port " ~a: ~a" 'field (field-getter record))
+                ...
+                (format port ">")))
+            'name))))))
 
 (define (export-component component)
   (let ((name (record-type-name component))
@@ -106,14 +123,16 @@
        (register-components key
                            (map (lambda (c) (car c)) nc)
                            components)
-       key))))
+       (cons key nc)))))
 
 (define (remove-entity key)
   (lambda (entities components)
-    (let ((clist (map (lambda (c) (car c)) (assoc-ref entities key))))
+    (let ((clist (map (lambda (c) (car c)) (assoc-ref entities key)))
+         (entity (assoc key entities)))
       (values
        (assoc-remove! entities key)
-       (unregister-components key clist components)))))
+       (unregister-components key clist components)
+       entity))))
 
 (define (set-entity key . new-components)
   (lambda (entities components)
@@ -123,7 +142,8 @@
       (values
        (assoc-set! entities key nc)
        (register-components key (lset-difference eq? nclist clist)
-                           (unregister-components key (lset-difference eq? clist nclist) components))))))
+                           (unregister-components key (lset-difference eq? clist nclist) components))
+       (cons key nc)))))
 
 (define (set-entity-components key . new-components)
   (lambda (entities components)
@@ -135,7 +155,8 @@
        nc)
       (values
        (assoc-set! entities key clist)
-       (register-components key (map (lambda (c) (car c)) nc) components)))))
+       (register-components key (map (lambda (c) (car c)) nc) components)
+       (cons key clist)))))
 
 (define (remove-entity-components key . old-components)
   (lambda (entities components)
@@ -146,7 +167,8 @@
        old-components)
       (values
        (assoc-set! entities key clist)
-       (unregister-components key old-components components)))))
+       (unregister-components key old-components components)
+       (cons key clist)))))
 
 (define (modify-entities changes entities components)
   (cond ((null? changes)
@@ -173,19 +195,33 @@
           (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-syntax make-system
+  (syntax-rules ()
+    ((_ ((name (component-type ...)) ...) form ...)
+     (lambda (entities components)
+       (let ((name (map (lambda (x)
+                         (cons (car x)
+                               (filter (lambda (x)
+                                         (memq (car x) '(component-type ...)))
+                                       (cdr x))))
+                       (map (lambda (x)
+                              (assoc x entities))
+                            (find-entities-by-components components '(component-type ...)))))
+            ...)
+        (let ((res (begin form ...)))
+          (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-syntax define-system
+  (syntax-rules ()
+    ((_ system-name ((name (component-type ...)) ...) form ...)
+     (define system-name
+       (make-system ((name (component-type ...)) ...)
+         form
+        ...)))))
 
 (define (join-systems . systems)
   (lambda (entities components)
@@ -196,7 +232,6 @@
             (receive (e2 c2) (((car s) e c))
               (run (cdr s) e2 c2)))))))
 
-
 (define (threaded-systems . systems)
   (lambda (entities components)
     (let run-wait ((thd
@@ -212,8 +247,20 @@
             (receive (e2 c2) ((join-thread (car thd)) e c)
               (run-wait (cdr thd) e2 c2)))))))
 
-
 (export find-entities-by-components
+       define-system
        make-system
        join-systems
        threaded-systems)
+
+
+;;; Entities and components access inside systems
+
+(define (get-key entity)
+  (car entity))
+
+(define (get-component component-name entity)
+  (assoc-ref (cdr entity) component-name))
+
+(export get-key
+       get-component)