_tkagg.cpp

/* -*- mode: c++; c-basic-offset: 4 -*- */

/*
 * The Python Imaging Library.
 * $Id$
 *
 */

/* This is needed for (at least) Tk 8.4.1, otherwise the signature of
** Tk_PhotoPutBlock changes.
*/
#define USE_COMPOSITELESS_PHOTO_PUT_BLOCK

#include <Python.h>
#include <cstdlib>
#include <cstdio>
#include <sstream>

#include "py_converters.h"

extern "C"
{
#ifdef __APPLE__
#  ifdef TK_FRAMEWORK
#     include <Tcl/tcl.h>
#     include <Tk/tk.h>
#  else
#     include <tk.h>
#  endif
#else
#  include <tk.h>
#endif
}

#if defined(_MSC_VER)
#  define SIZE_T_FORMAT "%Iu"
#else
#  define SIZE_T_FORMAT "%zu"
#endif

typedef struct
{
    PyObject_HEAD;
    Tcl_Interp *interp;
} TkappObject;

static int PyAggImagePhoto(ClientData clientdata, Tcl_Interp *interp, int argc, char **argv)
{
    Tk_PhotoHandle photo;
    Tk_PhotoImageBlock block;
    PyObject *bufferobj;

    // vars for blitting
    PyObject *bboxo;

    size_t aggl, bboxl;
    bool has_bbox;
    uint8_t *destbuffer;
    int destx, desty, destwidth, destheight, deststride;
    //unsigned long tmp_ptr;

    long mode;
    long nval;
    if (Tk_MainWindow(interp) == NULL) {
        // Will throw a _tkinter.TclError with "this isn't a Tk application"
        return TCL_ERROR;
    }

    if (argc != 5) {
        Tcl_AppendResult(interp, "usage: ", argv[0], " destPhoto srcImage", (char *)NULL);
        return TCL_ERROR;
    }

    /* get Tcl PhotoImage handle */
    photo = Tk_FindPhoto(interp, argv[1]);
    if (photo == NULL) {
        Tcl_AppendResult(interp, "destination photo must exist", (char *)NULL);
        return TCL_ERROR;
    }
    /* get array (or object that can be converted to array) pointer */
    if (sscanf(argv[2], SIZE_T_FORMAT, &aggl) != 1) {
        Tcl_AppendResult(interp, "error casting pointer", (char *)NULL);
        return TCL_ERROR;
    }
    bufferobj = (PyObject *)aggl;

    numpy::array_view<uint8_t, 3> buffer;
    try {
        buffer = numpy::array_view<uint8_t, 3>(bufferobj);
    } catch (...) {
        Tcl_AppendResult(interp, "buffer is of wrong type", (char *)NULL);
        PyErr_Clear();
        return TCL_ERROR;
    }
    int srcheight = buffer.dim(0);

    /* XXX insert aggRenderer type check */

    /* get array mode (0=mono, 1=rgb, 2=rgba) */
    mode = atol(argv[3]);
    if ((mode != 0) && (mode != 1) && (mode != 2)) {
        Tcl_AppendResult(interp, "illegal image mode", (char *)NULL);
        return TCL_ERROR;
    }

    /* check for bbox/blitting */
    if (sscanf(argv[4], SIZE_T_FORMAT, &bboxl) != 1) {
        Tcl_AppendResult(interp, "error casting pointer", (char *)NULL);
        return TCL_ERROR;
    }
    bboxo = (PyObject *)bboxl;

    if (bboxo != NULL && bboxo != Py_None) {
        agg::rect_d rect;
        if (!convert_rect(bboxo, &rect)) {
            return TCL_ERROR;
        }

        has_bbox = true;

        destx = (int)rect.x1;
        desty = srcheight - (int)rect.y2;
        destwidth = (int)(rect.x2 - rect.x1);
        destheight = (int)(rect.y2 - rect.y1);
        deststride = 4 * destwidth;

        destbuffer = new agg::int8u[deststride * destheight];
        if (destbuffer == NULL) {
            Tcl_AppendResult(interp, "could not allocate memory", (char *)NULL);
            return TCL_ERROR;
        }

        for (int i = 0; i < destheight; ++i) {
            memcpy(destbuffer + (deststride * i),
                   &buffer(i + desty, destx, 0),
                   deststride);
        }
    } else {
        has_bbox = false;
        destbuffer = NULL;
        destx = desty = destwidth = destheight = deststride = 0;
    }

    /* setup tkblock */
    block.pixelSize = 1;
    if (mode == 0) {
        block.offset[0] = block.offset[1] = block.offset[2] = 0;
        nval = 1;
    } else {
        block.offset[0] = 0;
        block.offset[1] = 1;
        block.offset[2] = 2;
        if (mode == 1) {
            block.offset[3] = 0;
            block.pixelSize = 3;
            nval = 3;
        } else {
            block.offset[3] = 3;
            block.pixelSize = 4;
            nval = 4;
        }
    }

    if (has_bbox) {
        block.width = destwidth;
        block.height = destheight;
        block.pitch = deststride;
        block.pixelPtr = destbuffer;

        Tk_PhotoPutBlock(photo, &block, destx, desty, destwidth, destheight);
        delete[] destbuffer;

    } else {
        block.width = buffer.dim(1);
        block.height = buffer.dim(0);
        block.pitch = (int)block.width * nval;
        block.pixelPtr = buffer.data();

        /* Clear current contents */
        Tk_PhotoBlank(photo);
        /* Copy opaque block to photo image, and leave the rest to TK */
        Tk_PhotoPutBlock(photo, &block, 0, 0, block.width, block.height);
    }

    return TCL_OK;
}

static PyObject *_pyobj_addr(PyObject *self, PyObject *args)
{
    PyObject *pyobj;
    if (!PyArg_ParseTuple(args, "O", &pyobj)) {
        return NULL;
    }
    return Py_BuildValue("n", (Py_ssize_t)pyobj);
}

static PyObject *_tkinit(PyObject *self, PyObject *args)
{
    Tcl_Interp *interp;
    TkappObject *app;

    Py_ssize_t arg;
    int is_interp;
    if (!PyArg_ParseTuple(args, "ni", &arg, &is_interp)) {
        return NULL;
    }

    if (is_interp) {
        interp = (Tcl_Interp *)arg;
    } else {
        /* Do it the hard way.  This will break if the TkappObject
           layout changes */
        app = (TkappObject *)arg;
        interp = app->interp;
    }

    /* This will bomb if interp is invalid... */

    Tcl_CreateCommand(interp,
                      "PyAggImagePhoto",
                      (Tcl_CmdProc *)PyAggImagePhoto,
                      (ClientData)0,
                      (Tcl_CmdDeleteProc *)NULL);

    Py_INCREF(Py_None);
    return Py_None;
}

static PyMethodDef functions[] = {
    /* Tkinter interface stuff */
    { "_pyobj_addr", (PyCFunction)_pyobj_addr, 1 }, { "tkinit", (PyCFunction)_tkinit, 1 },
    { NULL, NULL } /* sentinel */
};

#if PY3K
static PyModuleDef _tkagg_module = { PyModuleDef_HEAD_INIT, "_tkagg", "",   -1,  functions,
                                     NULL,                  NULL,     NULL, NULL };

PyMODINIT_FUNC PyInit__tkagg(void)
{
    PyObject *m;

    m = PyModule_Create(&_tkagg_module);

    import_array();

    return m;
}
#else
PyMODINIT_FUNC init_tkagg(void)
{
    import_array();

    Py_InitModule("_tkagg", functions);
}
#endif