pygimp: adds proper support for layer groups

Layer groups where barely supported using numeric IDs and
by calling gimp.Item.from_id. This adds a Python
GroupLayer class.

plug-ins/pygimp/gimpmodule.c

@@ -1770,6 +1770,8 @@ static struct _PyGimp_Functions pygimp_api_functions = {
     pygimp_drawable_new,
     &PyGimpLayer_Type,
     pygimp_layer_new,
+    &PyGimpGroupLayer_Type,
+    pygimp_group_layer_new,
     &PyGimpChannel_Type,
     pygimp_channel_new,
     &PyGimpVectors_Type,
@@ -1820,6 +1822,12 @@ initgimp(void)
     if (PyType_Ready(&PyGimpLayer_Type) < 0)
         return;
 
+    PyGimpGroupLayer_Type.ob_type = &PyType_Type;
+    PyGimpGroupLayer_Type.tp_alloc = PyType_GenericAlloc;
+    PyGimpGroupLayer_Type.tp_new = PyType_GenericNew;
+    if (PyType_Ready(&PyGimpGroupLayer_Type) < 0)
+        return;
+
     PyGimpChannel_Type.ob_type = &PyType_Type;
     PyGimpChannel_Type.tp_alloc = PyType_GenericAlloc;
     PyGimpChannel_Type.tp_new = PyType_GenericNew;
@@ -1901,6 +1909,9 @@ initgimp(void)
 
     Py_INCREF(&PyGimpLayer_Type);
     PyModule_AddObject(m, "Layer", (PyObject *)&PyGimpLayer_Type);
+    
+    Py_INCREF(&PyGimpGroupLayer_Type);
+    PyModule_AddObject(m, "GroupLayer", (PyObject *)&PyGimpGroupLayer_Type);
 
     Py_INCREF(&PyGimpChannel_Type);
     PyModule_AddObject(m, "Channel", (PyObject *)&PyGimpChannel_Type);

plug-ins/pygimp/pygimp-api.h

@@ -37,7 +37,7 @@ typedef struct {
     PyObject_HEAD
     gint32 ID;
     GimpDrawable *drawable;
-} PyGimpDrawable, PyGimpLayer, PyGimpChannel;
+} PyGimpDrawable, PyGimpLayer, PyGimpGroupLayer, PyGimpChannel;
 
 typedef struct {
     PyObject_HEAD
@@ -60,6 +60,9 @@ struct _PyGimp_Functions {
     PyTypeObject *Layer_Type;
     PyObject *(* layer_new)(gint32 ID);
 
+    PyTypeObject *GroupLayer_Type;
+    PyObject *(* group_layer_new)(gint32 ID);
+
     PyTypeObject *Channel_Type;
     PyObject *(* channel_new)(gint32 ID);
 
@@ -87,6 +90,8 @@ struct _PyGimp_Functions *_PyGimp_API;
 #define pygimp_drawable_new     (_PyGimp_API->drawable_new)
 #define PyGimpLayer_Type        (_PyGimp_API->Layer_Type)
 #define pygimp_layer_new        (_PyGimp_API->layer_new)
+#define PyGimpGroupLayer_Type   (_PyGimp_API->GroupLayer_Type)
+#define pygimp_group_layer_new  (_PyGimp_API->group_layer_new)
 #define PyGimpChannel_Type      (_PyGimp_API->Channel_Type)
 #define pygimp_channel_new      (_PyGimp_API->channel_new)
 #define PyGimpVectors_Type      (_PyGimp_API->Vectors_Type)

plug-ins/pygimp/pygimp-drawable.c

@@ -1923,6 +1923,118 @@ pygimp_layer_new(gint32 ID)
 /* End of code for Layer objects */
 /* -------------------------------------------------------- */
 
+static PyMethodDef grouplay_methods[] = {
+    {NULL,              NULL}           /* sentinel */
+};
+
+static PyObject *
+grouplay_get_layers(PyGimpGroupLayer *self, void *closure)
+{
+    gint32 *layers;
+    gint n_layers, i;
+    PyObject *ret;
+
+    layers = gimp_item_get_children(self->ID, &n_layers);
+
+    ret = PyList_New(n_layers);
+
+    for (i = 0; i < n_layers; i++)
+        PyList_SetItem(ret, i, pygimp_group_layer_new(layers[i]));
+
+    g_free(layers);
+
+    return ret;
+}
+
+static PyGetSetDef grouplay_getsets[] = {
+    { "layers", (getter)grouplay_get_layers, (setter)0 },
+    { NULL, (getter)0, (setter)0 }
+};
+
+static PyObject *
+grouplay_repr(PyGimpLayer *self)
+{
+    PyObject *s;
+    gchar *name;
+
+    name = gimp_item_get_name(self->ID);
+    s = PyString_FromFormat("<gimp.GroupLayer '%s'>", name ? name : "(null)");
+    g_free(name);
+
+    return s;
+}
+
+PyTypeObject PyGimpGroupLayer_Type = {
+    PyObject_HEAD_INIT(NULL)
+    0,                                  /* ob_size */
+    "gimp.GroupLayer",                  /* tp_name */
+    sizeof(PyGimpGroupLayer),                /* tp_basicsize */
+    0,                                  /* tp_itemsize */
+    /* methods */
+    (destructor)drw_dealloc,            /* tp_dealloc */
+    (printfunc)0,                       /* tp_print */
+    (getattrfunc)0,                     /* tp_getattr */
+    (setattrfunc)0,                     /* tp_setattr */
+    (cmpfunc)drw_cmp,                   /* tp_compare */
+    (reprfunc)grouplay_repr,                 /* tp_repr */
+    0,                                  /* tp_as_number */
+    0,                                  /* tp_as_sequence */
+    0,                                  /* tp_as_mapping */
+    (hashfunc)0,                        /* tp_hash */
+    (ternaryfunc)0,                     /* tp_call */
+    (reprfunc)0,                        /* tp_str */
+    (getattrofunc)0,                    /* tp_getattro */
+    (setattrofunc)0,                    /* tp_setattro */
+    0,                                  /* tp_as_buffer */
+    Py_TPFLAGS_DEFAULT,                 /* tp_flags */
+    NULL, /* Documentation string */
+    (traverseproc)0,                    /* tp_traverse */
+    (inquiry)0,                         /* tp_clear */
+    (richcmpfunc)0,                     /* tp_richcompare */
+    0,                                  /* tp_weaklistoffset */
+    (getiterfunc)0,                     /* tp_iter */
+    (iternextfunc)0,                    /* tp_iternext */
+    grouplay_methods,                   /* tp_methods */
+    0,                                  /* tp_members */
+    grouplay_getsets,                        /* tp_getset */
+    &PyGimpLayer_Type,                  /* tp_base */
+    (PyObject *)0,                      /* tp_dict */
+    0,                                  /* tp_descr_get */
+    0,                                  /* tp_descr_set */
+    0,                                  /* tp_dictoffset */
+    (initproc)lay_init,                 /* tp_init */
+    (allocfunc)0,                       /* tp_alloc */
+    (newfunc)0,                         /* tp_new */
+};
+
+PyObject *
+pygimp_group_layer_new(gint32 ID)
+{
+    PyGimpGroupLayer *self;
+
+    if (!gimp_item_is_valid(ID) || !gimp_item_is_layer(ID)) {
+        Py_INCREF(Py_None);
+        return Py_None;
+    }
+    
+    if (!gimp_item_is_group(ID)) {
+        return pygimp_layer_new(ID);
+    }
+
+    self = PyObject_NEW(PyGimpGroupLayer, &PyGimpGroupLayer_Type);
+
+    if (self == NULL)
+        return NULL;
+
+    self->ID = ID;
+    self->drawable = NULL;
+
+    return (PyObject *)self;
+}
+
+/* End of code for GroupLayer objects */
+/* -------------------------------------------------------- */
+
 
 static PyObject *
 chn_copy(PyGimpChannel *self)

plug-ins/pygimp/pygimp-image.c

@@ -204,7 +204,7 @@ img_new_layer(PyGimpImage *self, PyObject *args, PyObject *kwargs)
         return NULL;
     }
 
-    return pygimp_layer_new(layer_id);
+    return pygimp_group_layer_new(layer_id);
 }
 
 
@@ -236,7 +236,7 @@ img_enable_undo(PyGimpImage *self)
 static PyObject *
 img_flatten(PyGimpImage *self)
 {
-    return pygimp_layer_new(gimp_image_flatten(self->ID));
+    return pygimp_group_layer_new(gimp_image_flatten(self->ID));
 }
 
 static PyObject *
@@ -316,7 +316,7 @@ img_merge_visible_layers(PyGimpImage *self, PyObject *args)
 	return NULL;
     }
 
-    return pygimp_layer_new(id);
+    return pygimp_group_layer_new(id);
 }
 
 static PyObject *
@@ -340,7 +340,7 @@ img_merge_down(PyGimpImage *self, PyObject *args)
 	return NULL;
     }
 
-    return pygimp_layer_new(id);
+    return pygimp_group_layer_new(id);
 }
 
 static PyObject *
@@ -359,7 +359,7 @@ img_pick_correlate_layer(PyGimpImage *self, PyObject *args)
 	return Py_None;
     }
 
-    return pygimp_layer_new(id);
+    return pygimp_group_layer_new(id);
 }
 
 static PyObject *
@@ -756,7 +756,7 @@ img_get_layer_by_tattoo(PyGimpImage *self, PyObject *args)
     if (!PyArg_ParseTuple(args, "i:get_layer_by_tattoo", &tattoo))
 	return NULL;
 
-    return pygimp_layer_new(gimp_image_get_layer_by_tattoo(self->ID, tattoo));
+    return pygimp_group_layer_new(gimp_image_get_layer_by_tattoo(self->ID, tattoo));
 }
 
 static PyObject *
@@ -1019,7 +1019,7 @@ img_get_active_layer(PyGimpImage *self, void *closure)
 	return Py_None;
     }
 
-    return pygimp_layer_new(id);
+    return pygimp_group_layer_new(id);
 }
 
 static int
@@ -1222,7 +1222,7 @@ img_get_layers(PyGimpImage *self, void *closure)
     ret = PyList_New(n_layers);
 
     for (i = 0; i < n_layers; i++)
-	PyList_SetItem(ret, i, pygimp_layer_new(layers[i]));
+	PyList_SetItem(ret, i, pygimp_group_layer_new(layers[i]));
 
     g_free(layers);
 

plug-ins/pygimp/pygimp.h

@@ -76,6 +76,10 @@ extern PyTypeObject PyGimpLayer_Type;
 #define pygimp_layer_check(v) (PyObject_TypeCheck(v, &PyGimpLayer_Type))
 PyObject *pygimp_layer_new(gint32 ID);
 
+extern PyTypeObject PyGimpGroupLayer_Type;
+#define pygimp_layer__group_check(v) (PyObject_TypeCheck(v, &PyGimpGroupLayer_Type))
+PyObject *pygimp_group_layer_new(gint32 ID);
+
 extern PyTypeObject PyGimpChannel_Type;
 #define pygimp_channel_check(v) (PyObject_TypeCheck(v, &PyGimpChannel_Type))
 PyObject *pygimp_channel_new(gint32 ID);