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/*
* PIL FreeType Driver
* $Id: _imagingft.c 2756 2006-06-19 06:07:18Z fredrik $
*
* a FreeType 2.X driver for PIL
*
* history:
* 2001-02-17 fl Created (based on old experimental freetype 1.0 code)
* 2001-04-18 fl Fixed some egcs compiler nits
* 2002-11-08 fl Added unicode support; more font metrics, etc
* 2003-05-20 fl Fixed compilation under 1.5.2 and newer non-unicode builds
* 2003-09-27 fl Added charmap encoding support
* 2004-05-15 fl Fixed compilation for FreeType 2.1.8
* 2004-09-10 fl Added support for monochrome bitmaps
* 2006-06-18 fl Fixed glyph bearing calculation
*
* Copyright (c) 1998-2006 by Secret Labs AB
*/
#include "Python.h"
#include "Imaging.h"
#ifndef USE_FREETYPE_2_0
/* undef/comment out to use freetype 2.0 */
#define USE_FREETYPE_2_1
#endif
#if defined(USE_FREETYPE_2_1)
/* freetype 2.1 and newer */
#include <ft2build.h>
#include FT_FREETYPE_H
#else
/* freetype 2.0 */
#include <freetype/freetype.h>
#endif
#if PY_VERSION_HEX < 0x01060000
#define PyObject_New PyObject_NEW
#define PyObject_Del PyMem_DEL
#endif
#if PY_VERSION_HEX >= 0x01060000
#if PY_VERSION_HEX < 0x02020000 || defined(Py_USING_UNICODE)
/* defining this enables unicode support (default under 1.6a1 and later) */
#define HAVE_UNICODE
#endif
#endif
#ifndef FT_LOAD_TARGET_MONO
#define FT_LOAD_TARGET_MONO FT_LOAD_MONOCHROME
#endif
/* -------------------------------------------------------------------- */
/* error table */
#undef FTERRORS_H
#undef __FTERRORS_H__
#define FT_ERRORDEF( e, v, s ) { e, s },
#define FT_ERROR_START_LIST {
#define FT_ERROR_END_LIST { 0, 0 } };
struct {
int code;
const char* message;
} ft_errors[] =
#include <freetype/fterrors.h>
/* -------------------------------------------------------------------- */
/* font objects */
static FT_Library library;
typedef struct {
PyObject_HEAD
FT_Face face;
} FontObject;
static PyTypeObject Font_Type;
/* round a 26.6 pixel coordinate to the nearest larger integer */
#define PIXEL(x) ((((x)+63) & -64)>>6)
static PyObject*
geterror(int code)
{
int i;
for (i = 0; ft_errors[i].message; i++)
if (ft_errors[i].code == code) {
PyErr_SetString(PyExc_IOError, ft_errors[i].message);
return NULL;
}
PyErr_SetString(PyExc_IOError, "unknown freetype error");
return NULL;
}
static PyObject*
getfont(PyObject* self_, PyObject* args, PyObject* kw)
{
/* create a font object from a file name and a size (in pixels) */
FontObject* self;
int error;
char* filename;
int size;
int index = 0;
unsigned char* encoding = NULL;
static char* kwlist[] = {
"filename", "size", "index", "encoding", NULL
};
if (!PyArg_ParseTupleAndKeywords(args, kw, "si|is", kwlist,
&filename, &size, &index, &encoding))
return NULL;
if (!library && FT_Init_FreeType(&library)) {
PyErr_SetString(
PyExc_IOError,
"cannot initialize FreeType library"
);
return NULL;
}
self = PyObject_New(FontObject, &Font_Type);
if (!self)
return NULL;
self->face = NULL;
error = FT_New_Face(library, filename, index, &self->face);
if (!error)
error = FT_Set_Pixel_Sizes(self->face, 0, size);
if (!error && encoding && strlen((char*) encoding) == 4) {
FT_Encoding encoding_tag = FT_MAKE_TAG(
encoding[0], encoding[1], encoding[2], encoding[3]
);
error = FT_Select_Charmap(self->face, encoding_tag);
}
if (error) {
Py_DECREF(self);
return geterror(error);
}
return (PyObject*) self;
}
static int
font_getchar(PyObject* string, int index, FT_ULong* char_out)
{
Py_UNICODE* p = PyUnicode_AS_UNICODE(string);
int size = PyUnicode_GET_SIZE(string);
if (index >= size)
return 0;
*char_out = p[index];
return 1;
}
static PyObject*
font_getsize(FontObject* self, PyObject* args)
{
int i, x;
FT_ULong ch;
FT_Face face;
int xoffset;
FT_Bool kerning = FT_HAS_KERNING(self->face);
FT_UInt last_index = 0;
/* calculate size and bearing for a given string */
PyObject* string;
if (!PyArg_ParseTuple(args, "O:getsize", &string))
return NULL;
if (!PyUnicode_Check(string)) {
PyErr_SetString(PyExc_TypeError, "expected string");
return NULL;
}
face = NULL;
xoffset = 0;
for (x = i = 0; font_getchar(string, i, &ch); i++) {
int index, error;
face = self->face;
index = FT_Get_Char_Index(face, ch);
if (kerning && last_index && index) {
FT_Vector delta;
FT_Get_Kerning(self->face, last_index, index, ft_kerning_default,
&delta);
x += delta.x;
}
error = FT_Load_Glyph(face, index, FT_LOAD_DEFAULT);
if (error)
return geterror(error);
if (i == 0)
xoffset = face->glyph->metrics.horiBearingX;
x += face->glyph->metrics.horiAdvance;
last_index = index;
}
if (face) {
int offset;
/* left bearing */
if (xoffset < 0)
x -= xoffset;
else
xoffset = 0;
/* right bearing */
offset = face->glyph->metrics.horiAdvance -
face->glyph->metrics.width -
face->glyph->metrics.horiBearingX;
if (offset < 0)
x -= offset;
}
return Py_BuildValue(
"(ii)(ii)",
PIXEL(x), PIXEL(self->face->size->metrics.height),
PIXEL(xoffset), 0
);
}
static PyObject*
font_getabc(FontObject* self, PyObject* args)
{
FT_ULong ch;
FT_Face face;
double a, b, c;
/* calculate ABC values for a given string */
PyObject* string;
if (!PyArg_ParseTuple(args, "O:getabc", &string))
return NULL;
if (!PyUnicode_Check(string)) {
PyErr_SetString(PyExc_TypeError, "expected string");
return NULL;
}
if (font_getchar(string, 0, &ch)) {
int index, error;
face = self->face;
index = FT_Get_Char_Index(face, ch);
error = FT_Load_Glyph(face, index, FT_LOAD_DEFAULT);
if (error)
return geterror(error);
a = face->glyph->metrics.horiBearingX / 64.0;
b = face->glyph->metrics.width / 64.0;
c = (face->glyph->metrics.horiAdvance -
face->glyph->metrics.horiBearingX -
face->glyph->metrics.width) / 64.0;
} else
a = b = c = 0.0;
return Py_BuildValue("ddd", a, b, c);
}
static PyObject*
font_render(FontObject* self, PyObject* args)
{
int i, x, y;
Imaging im;
int index, error, ascender;
int load_flags;
unsigned char *source;
FT_ULong ch;
FT_GlyphSlot glyph;
FT_Bool kerning = FT_HAS_KERNING(self->face);
FT_UInt last_index = 0;
/* render string into given buffer (the buffer *must* have
the right size, or this will crash) */
PyObject* string;
long id;
int mask = 0;
if (!PyArg_ParseTuple(args, "Ol|i:render", &string, &id, &mask))
return NULL;
if (!PyUnicode_Check(string)) {
PyErr_SetString(PyExc_TypeError, "expected string");
return NULL;
}
im = (Imaging) id;
load_flags = FT_LOAD_RENDER;
if (mask)
load_flags |= FT_LOAD_TARGET_MONO;
for (x = i = 0; font_getchar(string, i, &ch); i++) {
if (i == 0 && self->face->glyph->metrics.horiBearingX < 0)
x = PIXEL(self->face->glyph->metrics.horiBearingX);
index = FT_Get_Char_Index(self->face, ch);
if (kerning && last_index && index) {
FT_Vector delta;
FT_Get_Kerning(self->face, last_index, index, ft_kerning_default,
&delta);
x += delta.x >> 6;
}
error = FT_Load_Glyph(self->face, index, load_flags);
if (error)
return geterror(error);
glyph = self->face->glyph;
if (mask) {
/* use monochrome mask (on palette images, etc) */
int xx, x0, x1;
source = (unsigned char*) glyph->bitmap.buffer;
ascender = PIXEL(self->face->size->metrics.ascender);
xx = x + glyph->bitmap_left;
x0 = 0;
x1 = glyph->bitmap.width;
if (xx < 0)
x0 = -xx;
if (xx + x1 > im->xsize)
x1 = im->xsize - xx;
for (y = 0; y < glyph->bitmap.rows; y++) {
int yy = y + ascender - glyph->bitmap_top;
if (yy >= 0 && yy < im->ysize) {
/* blend this glyph into the buffer */
unsigned char *target = im->image8[yy] + xx;
int i, j, m = 128;
for (i = j = 0; j < x1; j++) {
if (j >= x0 && (source[i] & m))
target[j] = 255;
if (!(m >>= 1)) {
m = 128;
i++;
}
}
}
source += glyph->bitmap.pitch;
}
} else {
/* use antialiased rendering */
int xx, x0, x1;
source = (unsigned char*) glyph->bitmap.buffer;
ascender = PIXEL(self->face->size->metrics.ascender);
xx = x + glyph->bitmap_left;
x0 = 0;
x1 = glyph->bitmap.width;
if (xx < 0)
x0 = -xx;
if (xx + x1 > im->xsize)
x1 = im->xsize - xx;
for (y = 0; y < glyph->bitmap.rows; y++) {
int yy = y + ascender - glyph->bitmap_top;
if (yy >= 0 && yy < im->ysize) {
/* blend this glyph into the buffer */
int i;
unsigned char *target = im->image8[yy] + xx;
for (i = x0; i < x1; i++) {
if (target[i] < source[i])
target[i] = source[i];
}
}
source += glyph->bitmap.pitch;
}
}
x += PIXEL(glyph->metrics.horiAdvance);
last_index = index;
}
Py_INCREF(Py_None);
return Py_None;
}
static void
font_dealloc(FontObject* self)
{
if (self->face)
FT_Done_Face(self->face);
PyObject_Del(self);
}
static PyMethodDef font_methods[] = {
{"render", (PyCFunction) font_render, METH_VARARGS},
{"getsize", (PyCFunction) font_getsize, METH_VARARGS},
{"getabc", (PyCFunction) font_getabc, METH_VARARGS},
{NULL, NULL}
};
static PyObject*
font_getattr(FontObject* self, char* name)
{
PyObject* res;
res = PyObject_GenericGetAttr((PyObject *)self,
PyUnicode_FromString(name));
if (res)
return res;
PyErr_Clear();
/* attributes */
if (!strcmp(name, "family"))
return PyUnicode_FromString(self->face->family_name);
if (!strcmp(name, "style"))
return PyUnicode_FromString(self->face->style_name);
if (!strcmp(name, "ascent"))
return PyLong_FromLong(PIXEL(self->face->size->metrics.ascender));
if (!strcmp(name, "descent"))
return PyLong_FromLong(-PIXEL(self->face->size->metrics.descender));
if (!strcmp(name, "glyphs"))
/* number of glyphs provided by this font */
return PyLong_FromLong(self->face->num_glyphs);
PyErr_SetString(PyExc_AttributeError, name);
return NULL;
}
static PyTypeObject Font_Type = {
PyVarObject_HEAD_INIT(NULL, 0)
"Font", sizeof(FontObject), 0,
/* methods */
(destructor)font_dealloc, /* tp_dealloc */
0, /* tp_print */
(getattrfunc)font_getattr, /* tp_getattr */
0, /* tp_setattr */
0, /* tp_compare */
0, /* tp_repr */
0, /* tp_as_number */
0, /* tp_as_sequence */
0, /* tp_as_mapping */
0, /* tp_hash */
0, /* tp_call */
0, /* tp_str */
0, /* tp_getattro */
0, /* tp_setattro */
0, /* tp_as_buffer */
0, /* tp_flags */
0, /* tp_doc */
0, /* tp_traverse */
0, /* tp_clear */
0, /* tp_richcompare */
0, /* tp_weaklistoffset */
0, /* tp_iter */
0, /* tp_iternext */
font_methods, /* tp_methods */
};
static PyMethodDef _functions[] = {
{"getfont", (PyCFunction) getfont, METH_VARARGS|METH_KEYWORDS},
{NULL, NULL}
};
static struct PyModuleDef _imagingftmodule = {
PyModuleDef_HEAD_INIT, /* m_base */
"_imagingft", /* m_name */
NULL, /* m_doc */
-1, /* m_size */
_functions, /* m_methods */
};
PyMODINIT_FUNC
PyInit__imagingft(void)
{
/* Patch object type */
Py_TYPE(&Font_Type) = &PyType_Type;
return PyModule_Create(&_imagingftmodule);
}
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