Using make-instance to create surfaces from PNG images

[clg] / gffi / basic-types.lisp

diff --git a/gffi/basic-types.lisp b/gffi/basic-types.lisp
index d1da957..9b3695e 100644 (file)
--- a/gffi/basic-types.lisp
+++ b/gffi/basic-types.lisp
@@ -20,7 +20,7 @@
 ;; TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
 ;; SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 
-;; $Id: basic-types.lisp,v 1.2 2006-06-08 13:24:25 espen Exp $
+;; $Id: basic-types.lisp,v 1.5 2007-01-02 15:20:32 espen Exp $
 
 (in-package "GFFI")
 
@@ -514,6 +514,12 @@ have been written as temporal.")
       #+(or cmu sbcl)(sap-ref-double location offset)
       #+clisp(ffi:memory-as location 'double-float offset)))
 
+(deftype optimized-double-float () 'double-float)
+
+(define-type-method to-alien-form ((type optimized-double-float) form &optional copy-p)
+  (declare (ignore type copy-p))
+  form)
+
 
 
 ;;; Character
@@ -570,6 +576,7 @@ have been written as temporal.")
 ;;; String
 
 (defun utf8-length (string)
+  "Returns the length including the trailing zero, of STRING encoded as UTF8"
   (1+ (loop
        for char across string
        as char-code = (char-code char)
@@ -580,7 +587,8 @@ have been written as temporal.")
            ((< char-code #x1FFFFF) 4)))))
 
 (defun encode-utf8-string (string &optional location)
-  (let ((location (or location (allocate-memory (utf8-length string)))))
+  (let* ((len (utf8-length string))
+        (location (or location (allocate-memory len))))
     (loop
      for char across string
      for i from 0
@@ -599,8 +607,8 @@ have been written as temporal.")
           ((< char-code #x80) (setf (ref-byte location i) char-code))
           ((< char-code #x800) (encode 11))
           ((< char-code #x10000) (encode 16))
-          ((< char-code #x200000) (encode 21))))
-     finally (setf (ref-byte location (1+ i)) 0))
+          ((< char-code #x200000) (encode 21)))))
+    (setf (ref-byte location (1- len)) 0)
     location))
 
 (defun decode-utf8-string (c-string)