dimension2d as a foreign record type

[guile-irrlicht.git] / irrlicht / util.scm

diff --git a/irrlicht/util.scm b/irrlicht/util.scm
index 8c5b9e4eb4651465c38ffda5b64d101a8623c4e6..9110be9fd53a3a311e394bf9feb2e0951b8e13f0 100644 (file)
--- a/irrlicht/util.scm
+++ b/irrlicht/util.scm
@@ -19,11 +19,133 @@
 
 
 (define-module (irrlicht util)
+  #:use-module (system foreign)
+  #:use-module (srfi srfi-1)
+  #:use-module (srfi srfi-9)
+  #:use-module (srfi srfi-9 gnu)
   #:export (bool->integer
-            integer->bool))
+            integer->bool
+            define-foreign
+            define-foreign-record-type
+            foreign-record-pointer))
 
 (define (bool->integer var)
   (if var 1 0))
 
 (define (integer->bool var)
   (if (= var 0) #f #t))
+
+;; Based on guile-sdl2 function, thanks a lot
+(define irrlicht-func
+  (let ((cirr (dynamic-link "libCIrrlicht")))
+    (lambda (return-type function-name arg-types)
+      (pointer->procedure return-type
+                          (dynamic-func function-name cirr)
+                          arg-types))))
+
+(define-syntax-rule (define-foreign name return-type func-name arg-types)
+  (define-public name
+    (irrlicht-func return-type func-name arg-types)))
+
+;; foreign struct record type
+(define-record-type standard-foreign-record-type
+  (make-foreign-record-type name types fields)
+  foreign-record-type?
+  (name foreign-record-type-name)
+  (types foreign-record-type-types)
+  (fields foreign-record-type-fields))
+
+(define-record-type foreign-record
+  (make-foreign-record type pointer)
+  foreign-record?
+  (type foreign-record-type)
+  (pointer foreign-record-pointer set-foreign-record-pointer!))
+
+(set-record-type-printer! foreign-record
+  (lambda (record port)
+    (format port "#<~a" (foreign-record-type-name (foreign-record-type record)))
+    (let* ((pointer (foreign-record-pointer record))
+           (record-type (foreign-record-type record))
+           (types (foreign-record-type-types record-type))
+           (fields (foreign-record-type-fields record-type))
+           (values (parse-c-struct pointer types)))
+      (for-each (lambda (field value)
+                  (format port " ~a: ~a" field value))
+                fields
+                values))
+    (format port ">")))
+
+(define-syntax define-foreign-record-type
+  (lambda (x)
+    (define (field-names field-specs)
+      (map (lambda (field-spec)
+             (syntax-case field-spec ()
+               ((name type getter) #'name)
+               ((name type getter setter) #'name)))
+           field-specs))
+
+    (define (field-types field-specs)
+      (map (lambda (field-spec)
+             (syntax-case field-spec ()
+               ((name type getter) #'type)
+               ((name type getter setter) #'type)))
+           field-specs))
+
+    (define (field-getters field-specs)
+      (map (lambda (field-spec field-id)
+             (syntax-case field-spec ()
+               ((name type getter) (list #'getter field-id))
+               ((name type getter setter) (list #'getter field-id))))
+           field-specs
+           (iota (length field-specs))))
+
+    (define (field-setters field-specs)
+      (filter-map (lambda (field-spec field-id)
+                    (syntax-case field-spec ()
+                      ((name type getter) #f)
+                      ((name type getter setter) (list #'setter field-id))))
+                  field-specs
+                  (iota (length field-specs))))
+
+    (syntax-case x ()
+      ((_ name (make-name make-arg ...) predicate? field-spec ...)
+       (with-syntax (((type-id ...) (field-types #'(field-spec ...)))
+                     ((field-name ...) (field-names #'(field-spec ...)))
+                     (((getter getter-id) ...) (field-getters #'(field-spec ...)))
+                     (((setter setter-id) ...) (field-setters #'(field-spec ...))))
+         #'(begin
+             (define name
+               (make-foreign-record-type
+                'name
+                (list type-id ...)
+                (list 'field-name ...)))
+
+             (define (make-name make-arg ...)
+               (let* ((types (foreign-record-type-types name))
+                      (c-struct-pointer (make-c-struct types (list make-arg ...))))
+                 (make-foreign-record name c-struct-pointer)))
+
+             (define (predicate? record)
+               (and
+                (foreign-record? record)
+                (let* ((record-type (foreign-record-type record))
+                       (type-name (foreign-record-type-name record-type)))
+                  (equal? type-name (foreign-record-type-name name)))))
+
+             (define (getter record)
+               (let* ((pointer (foreign-record-pointer record))
+                      (record-type (foreign-record-type record))
+                      (types (foreign-record-type-types record-type))
+                      (values (parse-c-struct pointer types)))
+                 (list-ref values getter-id)))
+             ...
+
+             (define (setter record new-value)
+               (let* ((pointer (foreign-record-pointer record))
+                      (record-type (foreign-record-type record))
+                      (types (foreign-record-type-types record-type))
+                      (values (parse-c-struct pointer types)))
+                 (list-set! values setter-id new-value)
+                 (set-foreign-record-pointer! record (make-c-struct types values))
+                 new-value))
+             ...))))))