[Help-smalltalk] Re: [OpenGL module] version 0.0b

[Paolo Bonzini]

> By the way, should I continue to post some new versions ? Are you
> interested by this module ?

I have a suggestion.

You can declare the Color, Point, etc. classes as either this:

Object variable: #float subclass: #Color
        instanceVariableNames: ''
        classVariableNames: ''
        poolDictionaries: ''
        category: ''!

Then, override new to be "^self basicNew: N" where N is the number of 
instance variables, and then add methods like

red
    ^self at: 1

red: aFloat
    self at: 1 put: aFloat

and so on.

(The same works for #double; you can also have an abstract class 
defining all these methods, and concrete classes for each type).

Then, apply the attached patch.  With it, you have a new way to pass 
arguments to C functions, #array, and if you have defined the classes as 
above, this new way maps naturally to the sole argument of functions 
like glColor3fv:

glColor3fv: color
    <cCall: 'glColor3fv' returning: #void args: #(#array)>!

This is also stored way way more efficiently.

Paolo

* local directory is at address@hidden/smalltalk--devo--2.2--patch-202
* comparing to address@hidden/smalltalk--devo--2.2--patch-202
M  ./doc/gst.texi
M  ./libgst/cint.c
M  ./libgst/sym.c
M  ./libgst/sym.h

* modified files

--- orig/doc/gst.texi
+++ mod/doc/gst.texi
@@ -2742,6 +2742,12 @@ C object value passed as @code{void *}
 Pointer to C object value passed as @code{void **}.  The @code{CObject}
 is modified on output to reflect the value stored into the passed object.
 
address@hidden array     
+The Smalltalk object must be of an indexable class; the pointer to the
+first indexed instance variable is passed.  The pointer might move
+upon garbage collection, so the object must either be fixed,
+or the called C routine should not call back to Smalltalk.
+
 @item smalltalk   
 Pass the object pointer to C.  The C routine should treat the value as a
 pointer to anonymous storage.  This pointer can be returned to Smalltalk
@@ -2767,6 +2773,7 @@ Table of parameter conversions:
 
 @multitable {Declared param type} {Boolean (True, False)} address@hidden (C 
promotion rule)}
 @item Declared param type @tab Object type          @tab C parameter type used
address@hidden array               @tab any indexable class  @tab void *
 @item boolean             @tab Boolean (True, False)@tab int
 @item byteArray           @tab ByteArray            @tab char *
 @item cObject             @tab CObject              @tab void *


--- orig/libgst/cint.c
+++ mod/libgst/cint.c
@@ -93,7 +93,8 @@ typedef enum
   CDATA_WCHAR,
   CDATA_WSTRING,
   CDATA_WSTRING_OUT,
-  CDATA_SYMBOL_OUT
+  CDATA_SYMBOL_OUT,
+  CDATA_ARRAY                  /* pass pointer to base for indexable objects */
 }
 cdata_type;
 
@@ -205,6 +206,9 @@ static void init_dld (void);
 PTR dld_open (const char *filename);
 
 /* Callout to tests callins.  */
+static void test_array (int *oopData);
+
+/* Callout to tests callins.  */
 static void test_callin (OOP oop);
 
 /* Callout to test the CString class */
@@ -273,6 +277,7 @@ static const char *c_type_name[] = {
   "wchar_t",                   /* CDATA_WCHAR */
   "wchar_t *",                 /* CDATA_WSTRING */
   "wchar_t *",                 /* CDATA_WSTRING_OUT */
+  "void *",                    /* CDATA_ARRAY */
 };
 
 /* A map between symbols and the cdata_type enum.  */
@@ -304,6 +309,7 @@ static const symbol_type_map type_map[] 
   {&_gst_wchar_symbol, CDATA_WCHAR},
   {&_gst_wstring_symbol, CDATA_WSTRING},
   {&_gst_wstring_out_symbol, CDATA_WSTRING_OUT},
+  {&_gst_array_symbol, CDATA_ARRAY},
   {NULL, CDATA_UNKNOWN}
 };
 
@@ -429,6 +435,13 @@ my_opendir (const char *dir)
 }
 
 void
+test_array (int *data)
+{
+  while (*data != -1)
+    printf ("%d ", *data++);
+}
+
+void
 test_callin (OOP oop)
 {
   OOP o, sel;
@@ -526,6 +539,7 @@ _gst_init_cfuncs (void)
   _gst_define_cfunc ("getArgv", get_argv);
 
   /* Test functions */
+  _gst_define_cfunc ("testArray", test_array);
   _gst_define_cfunc ("testCallin", test_callin);
   _gst_define_cfunc ("testCString", test_cstring);
   _gst_define_cfunc ("testCObjectPtr", test_cobject_ptr);
@@ -760,6 +774,7 @@ get_ffi_type (OOP returnTypeOOP)
   switch (TO_INT (returnTypeOOP))
     {
     case CDATA_OOP:
+    case CDATA_ARRAY:
     case CDATA_COBJECT:
     case CDATA_COBJECT_PTR:
     case CDATA_SYMBOL:
@@ -828,12 +843,12 @@ push_smalltalk_obj (OOP oop,
        oop == _gst_nil_oop ? CDATA_COBJECT :
        class == _gst_char_class ? CDATA_CHAR :
        class == _gst_unicode_character_class ? CDATA_WCHAR :
-       class == _gst_byte_array_class ? CDATA_BYTEARRAY : 
        is_a_kind_of (class, _gst_integer_class) ? CDATA_LONG :
-       is_a_kind_of (class, _gst_string_class) ? CDATA_STRING :
-       is_a_kind_of (class, _gst_unicode_string_class) ? CDATA_WSTRING :
        is_a_kind_of (class, _gst_c_object_class) ? CDATA_COBJECT :
        is_a_kind_of (class, _gst_float_class) ? CDATA_DOUBLE :
+       class == _gst_byte_array_class ? CDATA_BYTEARRAY : 
+       is_a_kind_of (class, _gst_string_class) ? CDATA_STRING :
+       is_a_kind_of (class, _gst_unicode_string_class) ? CDATA_WSTRING :
        CDATA_OOP;
       break;
 
@@ -873,6 +888,18 @@ push_smalltalk_obj (OOP oop,
       return;
     }
 
+  else if (cType == CDATA_ARRAY)
+    {
+      if (CLASS_IS_INDEXABLE (class))
+       {
+         int first = CLASS_FIXED_FIELDS (class);
+          cp->u.ptrVal = (PTR) &OOP_TO_OBJ (oop)->data[first];
+          INC_ADD_OOP (oop);   /* make sure it doesn't get gc'd */
+          SET_TYPE (&ffi_type_pointer);
+          return;
+       }
+    }
+
   else if (is_a_kind_of (class, _gst_integer_class))
     {
       switch (cType)
@@ -1027,7 +1054,6 @@ push_smalltalk_obj (OOP oop,
        }
     }
 
-
   bad_type (class, cType);
 }
 


--- orig/libgst/sym.c
+++ mod/libgst/sym.c
@@ -95,6 +95,7 @@ symbol_info;
 
 
 OOP _gst_and_symbol = NULL;
+OOP _gst_array_symbol = NULL;
 OOP _gst_as_scaled_decimal_scale_symbol = NULL;
 OOP _gst_at_put_symbol = NULL;
 OOP _gst_at_symbol = NULL;
@@ -278,6 +279,7 @@ static scope cur_scope = NULL;
    and is used to restore the global variables upon image load.  */
 static const symbol_info sym_info[] = {
   {&_gst_and_symbol, "and:"},
+  {&_gst_array_symbol, "array"},
   {&_gst_as_scaled_decimal_scale_symbol, "asScaledDecimal:scale:"},
   {&_gst_at_put_symbol, "at:put:"},
   {&_gst_at_symbol, "at:"},


--- orig/libgst/sym.h
+++ mod/libgst/sym.h
@@ -89,6 +89,7 @@ extern int _gst_use_undeclared
   ATTRIBUTE_HIDDEN;
 
 extern OOP _gst_and_symbol ATTRIBUTE_HIDDEN;
+extern OOP _gst_array_symbol ATTRIBUTE_HIDDEN;
 extern OOP _gst_as_scaled_decimal_scale_symbol ATTRIBUTE_HIDDEN;
 extern OOP _gst_at_put_symbol ATTRIBUTE_HIDDEN;
 extern OOP _gst_at_symbol ATTRIBUTE_HIDDEN;