Messy, but monumental: PyTexture::pyObject works

this also coincidentally fixes a weird bug I encountered while
(mis?)using tp_alloc: by using PyType_GenericAlloc, I avoid the segfault
that tp_alloc sometimes causes. See the horrible UIDrawable retrieval
macro that I use in UI.h for a workaround that can probably be replaced
with this technique

src/McRFPy_API.cpp

@@ -55,30 +55,37 @@ PyObject* PyInit_mcrfpy()
     
     // This code runs, but Python segfaults when accessing the UIFrame type.
     //std::cout << "Adding UIFrame object to module\n";
+    using namespace mcrfpydef;
+    PyTypeObject* pytypes[] = {&PyColorType, &PyFontType, &PyUICaptionType, &PyTextureType, &PyUISpriteType, &PyUIFrameType, &PyUICollectionType, 
+                               &PyUICollectionIterType, &PyUIGridPointType, &PyUIGridPointStateType, &PyUIEntityType, &PyUIEntityCollectionType,
+                               &PyUIEntityCollectionIterType, &PyUIGridType, nullptr};
+    int i = 0;
+    auto t = pytypes[i];
+    while (t != nullptr)
+    {
+        PyType_Ready(t);
+        PyModule_AddType(m, t);
+        t = pytypes[i++];
+    }
+    /*
     PyModule_AddType(m, &mcrfpydef::PyColorType);
     PyModule_AddType(m, &mcrfpydef::PyFontType);
     PyModule_AddType(m, &mcrfpydef::PyUICaptionType);
     PyModule_AddType(m, &mcrfpydef::PyTextureType);
     PyModule_AddType(m, &mcrfpydef::PyUISpriteType);
      
-    if (PyModule_AddType(m, &mcrfpydef::PyUIFrameType) < 0)
-    {
-        std::cout << "Error adding UIFrame type to module; aborting" << std::endl;
-        Py_DECREF(&mcrfpydef::PyUIFrameType);
-        return NULL;
-    }
+    PyModule_AddType(m, &mcrfpydef::PyUIFrameType);
     PyModule_AddType(m, &mcrfpydef::PyUICollectionType);
     PyModule_AddType(m, &mcrfpydef::PyUICollectionIterType);
 
     PyModule_AddType(m, &mcrfpydef::PyUIGridPointType);
     PyModule_AddType(m, &mcrfpydef::PyUIGridPointStateType);
     PyModule_AddType(m, &mcrfpydef::PyUIEntityType);
-
     PyModule_AddType(m, &mcrfpydef::PyUIEntityCollectionIterType);
     PyModule_AddType(m, &mcrfpydef::PyUIEntityCollectionType);
 
     PyModule_AddType(m, &mcrfpydef::PyUIGridType);
-
+    */
     
 
     return m;

src/PyTexture.cpp

@@ -1,4 +1,6 @@
 #include "PyTexture.h"
+using namespace mcrfpydef;
+
 
 PyTexture::PyTexture(std::string filename, int sprite_w, int sprite_h)
 : source(filename), sprite_width(sprite_w), sprite_height(sprite_h)
@@ -15,6 +17,17 @@ PyTexture::PyTexture(std::string filename, int sprite_w, int sprite_h)
     }
 }
 
+/* // bit misguided here: holding self might prevent the shared_ptr from ever being released.
+PyTexture::~PyTexture()
+{
+    if (self != NULL)
+    {
+        (PyTextureObject*)self->data.reset();
+        Py_DECREF(self);
+    }
+}
+*/
+
 sf::Sprite PyTexture::sprite(int index, sf::Vector2f pos,  sf::Vector2f s)
 {
     int tx = index % sheet_width, ty = index / sheet_width;
@@ -25,6 +38,28 @@ sf::Sprite PyTexture::sprite(int index, sf::Vector2f pos,  sf::Vector2f s)
     return sprite;
 }
 
+PyObject* PyTexture::pyObject()
+{
+    //PyTextureObject* self = (PyTextureObject*)pynew(&mcrfpydef::PyTextureType, NULL, NULL);
+    std::cout << "tp_alloc (GenericAlloc)" << std::endl;
+    //PyObject* obj = ((&PyTextureType)->tp_alloc(&PyTextureType, 0));
+    //PyObject* obj = pynew(&PyTextureType);
+    PyObject* obj = PyType_GenericAlloc(&PyTextureType, 0);
+    std::cout << "alloc worked" << std::endl;
+    //Py_INCREF(self);
+    try {
+        std::cout << "assign data to self" << std::endl;
+        ((PyTextureObject*)obj)->data = shared_from_this();
+    }
+    catch (std::bad_weak_ptr& e)
+    {
+        std::cout << "Bad weak ptr: shared_from_this() failed" << std::endl;
+    }
+    // TODO - shared_from_this will raise an exception if the object does not have a shared pointer. Constructor should be made private; write a factory function
+    std::cout << "returning PyObject" << std::endl;
+    return obj;
+}
+
 Py_hash_t PyTexture::hash(PyObject* obj)
 {
     auto self = (PyTextureObject*)obj;

src/PyTexture.h

@@ -2,22 +2,23 @@
 #include "Common.h"
 #include "Python.h"
 
-class PyTexture;
+namespace mcrfpydef {
+    class PyTexture;
 
-typedef struct {
+    typedef struct {
         PyObject_HEAD
             std::shared_ptr<PyTexture> data;
-} PyTextureObject;
+    } PyTextureObject;
 
-class PyTexture
-{
-private:
+    class PyTexture : public std::enable_shared_from_this<PyTexture>
+    {
+    private:
         sf::Texture texture;
         std::string source;
         int sheet_width, sheet_height;
-protected:
-    PyObject* self = 0;
-public:
+    protected:
+        //PyObject* self = 0;
+    public:
         int sprite_width, sprite_height; // just use them read only, OK?
         PyTexture(std::string filename, int sprite_w, int sprite_h);
         sf::Sprite sprite(int index, sf::Vector2f pos = sf::Vector2f(0, 0), sf::Vector2f s = sf::Vector2f(1.0, 1.0));
@@ -25,11 +26,11 @@ public:
         PyObject* pyObject();
         static Py_hash_t hash(PyObject*);
         static int init(PyTextureObject*, PyObject*, PyObject*);
-    static PyObject* pynew(PyTypeObject*, PyObject*, PyObject*);
-};
-/*
-static int PyTexture_init(PyTextureObject* self, PyObject* args, PyObject* kwds)
-{
+        static PyObject* pynew(PyTypeObject* type, PyObject* args=NULL, PyObject* kwds=NULL);
+    };
+    /*
+    static int PyTexture_init(PyTextureObject* self, PyObject* args, PyObject* kwds)
+    {
         //std::cout << "Init called\n";
         static const char* keywords[] = { "filename", "grid_size", "grid_width", "grid_height", nullptr };
         char* filename;
@@ -41,9 +42,8 @@ static int PyTexture_init(PyTextureObject* self, PyObject* args, PyObject* kwds)
         }
         self->data = std::make_shared<PyTexture>(filename, grid_size, grid_size);
         return 0;
-}
-*/
-namespace mcrfpydef {
+    }
+    */
     static PyTypeObject PyTextureType = {
         .tp_name = "mcrfpy.Texture",
         .tp_basicsize = sizeof(PyTextureObject),

src/UI.cpp

@@ -2,6 +2,8 @@
 #include "Resources.h"
 #include "GameEngine.h"
 
+using namespace mcrfpydef;
+
 /* //callability fields & methods
     PyObject* click_callable;
     virtual UIDrawable* click_at(sf::Vector2f point);
@@ -520,3 +522,8 @@ PyObjectsEnum UIGrid::derived_type()
 {
     return PyObjectsEnum::UIGRID;
 }
+
+std::shared_ptr<PyTexture> UIGrid::getTexture()
+{
+    return ptex;
+}

src/UI.h

@@ -8,6 +8,8 @@
 #include "PyCallable.h"
 #include "PyTexture.h"
 
+using namespace mcrfpydef;
+
 enum PyObjectsEnum : int
 {
     UIFRAME = 1,
@@ -187,6 +189,7 @@ public:
     sf::RectangleShape box;
     float center_x, center_y, zoom;
     //IndexTexture* itex;
+    std::shared_ptr<PyTexture> getTexture();
     sf::Sprite sprite, output;
     sf::RenderTexture renderTexture;
     std::vector<UIGridPoint> points;
@@ -1215,7 +1218,8 @@ static int PyUIDrawable_set_click(PyUIGridObject* self, PyObject* value, void* c
     
     static PyObject* PyUISprite_get_texture(PyUISpriteObject* self, void* closure)
     {
-        return NULL;
+        std::cout << "Calling pyObject" << std::endl;
+        return self->data->getTexture()->pyObject();
     }
     
     static int PyUISprite_set_texture(PyUISpriteObject* self, PyObject* value, void* closure)
@@ -1791,6 +1795,12 @@ static PyObject* PyUIGrid_get_texture(PyUIGridObject* self, void* closure) {
     return self->texture;
 }
 */
+static PyObject* PyUIGrid_get_texture(PyUIGridObject* self, void* closure) {
+        //return self->data->getTexture()->pyObject();
+        PyTextureObject* obj = (PyTextureObject*)((&PyTextureType)->tp_alloc(&PyTextureType, 0));
+        obj->data = self->data->getTexture();
+        return (PyObject*)obj;
+}
 
 static PyObject* PyUIGrid_at(PyUIGridObject* self, PyObject* o)
 {
@@ -1842,7 +1852,7 @@ static PyGetSetDef PyUIGrid_getsetters[] = {
 
     {"click", (getter)PyUIDrawable_get_click, (setter)PyUIDrawable_set_click, "Object called with (x, y, button) when clicked", (void*)PyObjectsEnum::UIGRID},
 
-    //{"texture", (getter)PyUIGrid_get_texture, NULL, "Texture of the grid", NULL}, //TODO 7DRL-day2-item5
+    {"texture", (getter)PyUIGrid_get_texture, NULL, "Texture of the grid", NULL}, //TODO 7DRL-day2-item5
     {NULL}  /* Sentinel */
 };