Re: [Denemo-devel] Transpose

[Jeremiah Benham]

On Mon, 2008-08-11 at 19:24 +0100, Richard Shann wrote:
> On Mon, 2008-08-11 at 09:23 -0500, Jeremiah Benham wrote:
> > No. I am going to have to read through the docs first. I will get
> > started on that now. 
> > 
> > > As I mentioned I
> > > could generate an interface to all the menu Actions callback
> > functions
> > > in a matter of minutes, given an example of the format required.
> > 
> > ok. I will get on that. 
> I've written a very simple example of generating an interface array
> the result looks like this:
> 
> 
> /* Interface (dummy) for a scripting engine */
> typedef struct  arraytype {
> char *command_name;
>  void* callback;
> }
> arraytype;
> arraytype interface_array[] = {
> {"Denemo_InsertBflatmaj",(void*) 0x816ac40},
> {"Denemo_StaffUp",(void*) 0x815ec98},
> {"Denemo_SetInitialDflatmaj",(void*) 0x816d920},
> {"Denemo_ToggleStartCrescendo",(void*) 0x8170ed0},
> {"Denemo_ToggleTenuto",(void*) 0x81710d8},

ok. I am a bit confused. I want to make sure I understand you. Is the
above char *command_name to be names of the functions exported that the
script writer will use? You are going to define this somewhere so that
it creates an alias to pointers pointing to the actual function? There
will need to be a header file containing something like
denemointerface.h:

void Denemo_InsertBflatmaj();
void Denemo_StaffUp();
etc .....

Then the denemointerface.i file would look like this:
%module denemointerface
%{
#include<denemointerface.h>
%}
external void Denemo_InsertBflatmaj();
external void Denemo_StaffUp();
etc .....

Am, I understanding this correctly? If so I can use the code you gave me
to auto-generate the above very easily. 

> and so on.
> The void* are the GtkAction pointers, so the call to
> ToggleStartCrescendo would call a function that would do
>  
> gtk_action_activate(0x8170ed0);

Would 0x8170ed0 always be the same each time denemo is launched or does
that dynamically change each time?

> For parameters, notice that there is a whole machinery GValue for
> passing parameters whose types can be determined.
> Here is a little snippet of code showing GValue in use:

So in this instance the alias would point to a GValue containing what?
the function name and its arguments?

> GValue *value = g_malloc0(sizeof(GValue));
>     g_value_init(value, G_TYPE_BOOLEAN);
>     g_value_set_boolean(value,Denemo.gui->textview &&
> GTK_WIDGET_VISIBLE(Denemo.gui->textwindow));
>     g_object_set_property (G_OBJECT (widget), "active", value);
> 
> though you wouldn't normally generate them on the heap.

Do you want this variable GENERATE_INTERFACE_TO_SCRIPTING_LANGUAGE to be
set by Autotools as a ./configure --enable-python --enable-ruby or what
is your plan. Is this something that would be turned off by default on
the next release? 

> I'm mentioning all this as I am scheduled to be in hospital Thursday
> this week, and hope to come back to find everything finished!

I hope you are going to be ok.  

Jeremiah

> Richard
> p.s. the code generating the above is this (at the end of view.c)
> 
> ...
>    GtkActionGroup *action_group;
>    GList *groups = gtk_ui_manager_get_action_groups (Denemo.ui_manager);
>    action_group = GTK_ACTION_GROUP(groups->data); 
>    GList *g = gtk_action_group_list_actions(action_group);
> #ifdef GENERATE_INTERFACE_TO_SCRIPTING_LANGUAGE
>      g_print("/* Interface (dummy) for a scripting engine */\n");
>      g_print("typedef struct  arraytype {\nchar *command_name;\n void*
> callback;\n}\narraytype;\n");
>      g_print("arraytype interface_array[] = {\n");
> #endif
>    for(;g;g=g->next) {
>      gint command_idx;
>      keymap *the_keymap = Denemo.prefs.the_keymap;
>      GSList *h = gtk_action_get_proxies (g->data);
>      for(;h;h=h->next) {
> #if (GTK_MINOR_VERSION <10)
>        attach_action_to_widget(h->data, g->data, Denemo.gui);
> #endif
>        attach_set_accel_callback(h->data, g->data,"", Denemo.gui);
>        command_idx = lookup_index_from_name(the_keymap,
>                                           gtk_action_get_name(g->data));
>        if (command_idx != -1) {
>        update_accel_labels(the_keymap, command_idx);
>        }
>      }
> #ifdef GENERATE_INTERFACE_TO_SCRIPTING_LANGUAGE
>      GtkAction *action = g->data;
>      g_print("{\"Denemo_%s\",(void*) %p},\n",
> gtk_action_get_name(action), action);
> #endif
>    }
> #ifdef GENERATE_INTERFACE_TO_SCRIPTING_LANGUAGE
>      
>      g_print("{\"\", 0x0}};\n");
> #endif
>    initialized = TRUE;
>  }
> ...
>