forked from python-pillow/Pillow
/
_imagingft.c
1422 lines (1253 loc) · 41 KB
/
_imagingft.c
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/*
* PIL FreeType Driver
*
* 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
* 2007-12-23 fl Fixed crash in family/style attribute fetch
* 2008-01-02 fl Handle Unicode filenames properly
*
* Copyright (c) 1998-2007 by Secret Labs AB
*/
#define PY_SSIZE_T_CLEAN
#include "Python.h"
#include "libImaging/Imaging.h"
#include <ft2build.h>
#include FT_FREETYPE_H
#include FT_GLYPH_H
#include FT_BITMAP_H
#include FT_STROKER_H
#include FT_MULTIPLE_MASTERS_H
#include FT_SFNT_NAMES_H
#ifdef FT_COLOR_H
#include FT_COLOR_H
#endif
#define KEEP_PY_UNICODE
#if !defined(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 } \
} \
;
#ifdef HAVE_RAQM
# ifdef HAVE_RAQM_SYSTEM
# include <raqm.h>
# else
# include "thirdparty/raqm/raqm.h"
# ifdef HAVE_FRIBIDI_SYSTEM
# include <fribidi.h>
# else
# include "thirdparty/fribidi-shim/fribidi.h"
# include <hb.h>
# endif
# endif
#endif
static int have_raqm = 0;
#define LAYOUT_FALLBACK 0
#define LAYOUT_RAQM 1
typedef struct {
int index, x_offset, x_advance, y_offset, y_advance;
unsigned int cluster;
} GlyphInfo;
struct {
int code;
const char *message;
} ft_errors[] =
#include FT_ERRORS_H
/* -------------------------------------------------------------------- */
/* font objects */
static FT_Library library;
typedef struct {
PyObject_HEAD FT_Face face;
unsigned char *font_bytes;
int layout_engine;
} FontObject;
static PyTypeObject Font_Type;
/* round a 26.6 pixel coordinate to the nearest integer */
#define PIXEL(x) ((((x) + 32) & -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_OSError, ft_errors[i].message);
return NULL;
}
}
PyErr_SetString(PyExc_OSError, "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 = 0;
char *filename = NULL;
Py_ssize_t size;
Py_ssize_t index = 0;
Py_ssize_t layout_engine = 0;
unsigned char *encoding;
unsigned char *font_bytes;
Py_ssize_t font_bytes_size = 0;
static char *kwlist[] = {
"filename", "size", "index", "encoding", "font_bytes", "layout_engine", NULL};
if (!library) {
PyErr_SetString(PyExc_OSError, "failed to initialize FreeType library");
return NULL;
}
if (!PyArg_ParseTupleAndKeywords(
args,
kw,
"etn|nsy#n",
kwlist,
Py_FileSystemDefaultEncoding,
&filename,
&size,
&index,
&encoding,
&font_bytes,
&font_bytes_size,
&layout_engine)) {
return NULL;
}
self = PyObject_New(FontObject, &Font_Type);
if (!self) {
if (filename) {
PyMem_Free(filename);
}
return NULL;
}
self->face = NULL;
self->layout_engine = layout_engine;
if (filename && font_bytes_size <= 0) {
self->font_bytes = NULL;
error = FT_New_Face(library, filename, index, &self->face);
} else {
/* need to have allocated storage for font_bytes for the life of the object.*/
/* Don't free this before FT_Done_Face */
self->font_bytes = PyMem_Malloc(font_bytes_size);
if (!self->font_bytes) {
error = 65; // Out of Memory in Freetype.
}
if (!error) {
memcpy(self->font_bytes, font_bytes, (size_t)font_bytes_size);
error = FT_New_Memory_Face(
library,
(FT_Byte *)self->font_bytes,
font_bytes_size,
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 (filename) {
PyMem_Free(filename);
}
if (error) {
if (self->font_bytes) {
PyMem_Free(self->font_bytes);
self->font_bytes = NULL;
}
Py_DECREF(self);
return geterror(error);
}
return (PyObject *)self;
}
static int
font_getchar(PyObject *string, int index, FT_ULong *char_out) {
if (PyUnicode_Check(string)) {
if (index >= PyUnicode_GET_LENGTH(string)) {
return 0;
}
*char_out = PyUnicode_READ_CHAR(string, index);
return 1;
}
return 0;
}
#ifdef HAVE_RAQM
static size_t
text_layout_raqm(
PyObject *string,
FontObject *self,
const char *dir,
PyObject *features,
const char *lang,
GlyphInfo **glyph_info,
int mask,
int color) {
size_t i = 0, count = 0, start = 0;
raqm_t *rq;
raqm_glyph_t *glyphs = NULL;
raqm_direction_t direction;
rq = raqm_create();
if (rq == NULL) {
PyErr_SetString(PyExc_ValueError, "raqm_create() failed.");
goto failed;
}
if (PyUnicode_Check(string)) {
Py_UCS4 *text = PyUnicode_AsUCS4Copy(string);
Py_ssize_t size = PyUnicode_GET_LENGTH(string);
if (!text || !size) {
/* return 0 and clean up, no glyphs==no size,
and raqm fails with empty strings */
goto failed;
}
int set_text = raqm_set_text(rq, text, size);
PyMem_Free(text);
if (!set_text) {
PyErr_SetString(PyExc_ValueError, "raqm_set_text() failed");
goto failed;
}
if (lang) {
if (!raqm_set_language(rq, lang, start, size)) {
PyErr_SetString(PyExc_ValueError, "raqm_set_language() failed");
goto failed;
}
}
} else {
PyErr_SetString(PyExc_TypeError, "expected string");
goto failed;
}
direction = RAQM_DIRECTION_DEFAULT;
if (dir) {
if (strcmp(dir, "rtl") == 0) {
direction = RAQM_DIRECTION_RTL;
} else if (strcmp(dir, "ltr") == 0) {
direction = RAQM_DIRECTION_LTR;
} else if (strcmp(dir, "ttb") == 0) {
direction = RAQM_DIRECTION_TTB;
#if !defined(RAQM_VERSION_ATLEAST)
/* RAQM_VERSION_ATLEAST was added in Raqm 0.7.0 */
PyErr_SetString(
PyExc_ValueError,
"libraqm 0.7 or greater required for 'ttb' direction");
goto failed;
#endif
} else {
PyErr_SetString(
PyExc_ValueError, "direction must be either 'rtl', 'ltr' or 'ttb'");
goto failed;
}
}
if (!raqm_set_par_direction(rq, direction)) {
PyErr_SetString(PyExc_ValueError, "raqm_set_par_direction() failed");
goto failed;
}
if (features != Py_None) {
int j, len;
PyObject *seq = PySequence_Fast(features, "expected a sequence");
if (!seq) {
goto failed;
}
len = PySequence_Fast_GET_SIZE(seq);
for (j = 0; j < len; j++) {
PyObject *item = PySequence_Fast_GET_ITEM(seq, j);
char *feature = NULL;
Py_ssize_t size = 0;
PyObject *bytes;
if (!PyUnicode_Check(item)) {
Py_DECREF(seq);
PyErr_SetString(PyExc_TypeError, "expected a string");
goto failed;
}
bytes = PyUnicode_AsUTF8String(item);
if (bytes == NULL) {
Py_DECREF(seq);
goto failed;
}
feature = PyBytes_AS_STRING(bytes);
size = PyBytes_GET_SIZE(bytes);
if (!raqm_add_font_feature(rq, feature, size)) {
Py_DECREF(seq);
Py_DECREF(bytes);
PyErr_SetString(PyExc_ValueError, "raqm_add_font_feature() failed");
goto failed;
}
Py_DECREF(bytes);
}
Py_DECREF(seq);
}
if (!raqm_set_freetype_face(rq, self->face)) {
PyErr_SetString(PyExc_RuntimeError, "raqm_set_freetype_face() failed.");
goto failed;
}
if (!raqm_layout(rq)) {
PyErr_SetString(PyExc_RuntimeError, "raqm_layout() failed.");
goto failed;
}
glyphs = raqm_get_glyphs(rq, &count);
if (glyphs == NULL) {
PyErr_SetString(PyExc_ValueError, "raqm_get_glyphs() failed.");
count = 0;
goto failed;
}
(*glyph_info) = PyMem_New(GlyphInfo, count);
if ((*glyph_info) == NULL) {
PyErr_SetString(PyExc_MemoryError, "PyMem_New() failed");
count = 0;
goto failed;
}
for (i = 0; i < count; i++) {
(*glyph_info)[i].index = glyphs[i].index;
(*glyph_info)[i].x_offset = glyphs[i].x_offset;
(*glyph_info)[i].x_advance = glyphs[i].x_advance;
(*glyph_info)[i].y_offset = glyphs[i].y_offset;
(*glyph_info)[i].y_advance = glyphs[i].y_advance;
(*glyph_info)[i].cluster = glyphs[i].cluster;
}
failed:
raqm_destroy(rq);
return count;
}
#endif
static size_t
text_layout_fallback(
PyObject *string,
FontObject *self,
const char *dir,
PyObject *features,
const char *lang,
GlyphInfo **glyph_info,
int mask,
int color) {
int error, load_flags;
FT_ULong ch;
Py_ssize_t count;
FT_GlyphSlot glyph;
FT_Bool kerning = FT_HAS_KERNING(self->face);
FT_UInt last_index = 0;
int i;
if (features != Py_None || dir != NULL || lang != NULL) {
PyErr_SetString(
PyExc_KeyError,
"setting text direction, language or font features is not supported "
"without libraqm");
}
if (!PyUnicode_Check(string)) {
PyErr_SetString(PyExc_TypeError, "expected string");
return 0;
}
count = 0;
while (font_getchar(string, count, &ch)) {
count++;
}
if (count == 0) {
return 0;
}
(*glyph_info) = PyMem_New(GlyphInfo, count);
if ((*glyph_info) == NULL) {
PyErr_SetString(PyExc_MemoryError, "PyMem_New() failed");
return 0;
}
load_flags = FT_LOAD_DEFAULT;
if (mask) {
load_flags |= FT_LOAD_TARGET_MONO;
}
#ifdef FT_LOAD_COLOR
if (color) {
load_flags |= FT_LOAD_COLOR;
}
#endif
for (i = 0; font_getchar(string, i, &ch); i++) {
(*glyph_info)[i].index = FT_Get_Char_Index(self->face, ch);
error = FT_Load_Glyph(self->face, (*glyph_info)[i].index, load_flags);
if (error) {
geterror(error);
return 0;
}
glyph = self->face->glyph;
(*glyph_info)[i].x_offset = 0;
(*glyph_info)[i].y_offset = 0;
if (kerning && last_index && (*glyph_info)[i].index) {
FT_Vector delta;
if (FT_Get_Kerning(
self->face,
last_index,
(*glyph_info)[i].index,
ft_kerning_default,
&delta) == 0) {
(*glyph_info)[i - 1].x_advance += PIXEL(delta.x);
(*glyph_info)[i - 1].y_advance += PIXEL(delta.y);
}
}
(*glyph_info)[i].x_advance = glyph->metrics.horiAdvance;
// y_advance is only used in ttb, which is not supported by basic layout
(*glyph_info)[i].y_advance = 0;
last_index = (*glyph_info)[i].index;
(*glyph_info)[i].cluster = ch;
}
return count;
}
static size_t
text_layout(
PyObject *string,
FontObject *self,
const char *dir,
PyObject *features,
const char *lang,
GlyphInfo **glyph_info,
int mask,
int color) {
size_t count;
#ifdef HAVE_RAQM
if (have_raqm && self->layout_engine == LAYOUT_RAQM) {
count = text_layout_raqm(
string, self, dir, features, lang, glyph_info, mask, color);
} else
#endif
{
count = text_layout_fallback(
string, self, dir, features, lang, glyph_info, mask, color);
}
return count;
}
static PyObject *
font_getlength(FontObject *self, PyObject *args) {
int length; /* length along primary axis, in 26.6 precision */
GlyphInfo *glyph_info = NULL; /* computed text layout */
size_t i, count; /* glyph_info index and length */
int horizontal_dir; /* is primary axis horizontal? */
int mask = 0; /* is FT_LOAD_TARGET_MONO enabled? */
int color = 0; /* is FT_LOAD_COLOR enabled? */
const char *mode = NULL;
const char *dir = NULL;
const char *lang = NULL;
PyObject *features = Py_None;
PyObject *string;
/* calculate size and bearing for a given string */
if (!PyArg_ParseTuple(
args, "O|zzOz:getlength", &string, &mode, &dir, &features, &lang)) {
return NULL;
}
horizontal_dir = dir && strcmp(dir, "ttb") == 0 ? 0 : 1;
mask = mode && strcmp(mode, "1") == 0;
color = mode && strcmp(mode, "RGBA") == 0;
count = text_layout(string, self, dir, features, lang, &glyph_info, mask, color);
if (PyErr_Occurred()) {
return NULL;
}
length = 0;
for (i = 0; i < count; i++) {
if (horizontal_dir) {
length += glyph_info[i].x_advance;
} else {
length -= glyph_info[i].y_advance;
}
}
if (glyph_info) {
PyMem_Free(glyph_info);
glyph_info = NULL;
}
return PyLong_FromLong(length);
}
static PyObject *
font_getsize(FontObject *self, PyObject *args) {
int position; /* pen position along primary axis, in 26.6 precision */
int advanced; /* pen position along primary axis, in pixels */
int px, py; /* position of current glyph, in pixels */
int x_min, x_max, y_min, y_max; /* text bounding box, in pixels */
int x_anchor, y_anchor; /* offset of point drawn at (0, 0), in pixels */
int load_flags; /* FreeType load_flags parameter */
int error;
FT_Face face;
FT_Glyph glyph;
FT_BBox bbox; /* glyph bounding box */
GlyphInfo *glyph_info = NULL; /* computed text layout */
size_t i, count; /* glyph_info index and length */
int horizontal_dir; /* is primary axis horizontal? */
int mask = 0; /* is FT_LOAD_TARGET_MONO enabled? */
int color = 0; /* is FT_LOAD_COLOR enabled? */
const char *mode = NULL;
const char *dir = NULL;
const char *lang = NULL;
const char *anchor = NULL;
PyObject *features = Py_None;
PyObject *string;
/* calculate size and bearing for a given string */
if (!PyArg_ParseTuple(
args, "O|zzOzz:getsize", &string, &mode, &dir, &features, &lang, &anchor)) {
return NULL;
}
horizontal_dir = dir && strcmp(dir, "ttb") == 0 ? 0 : 1;
mask = mode && strcmp(mode, "1") == 0;
color = mode && strcmp(mode, "RGBA") == 0;
if (anchor == NULL) {
anchor = horizontal_dir ? "la" : "lt";
}
if (strlen(anchor) != 2) {
goto bad_anchor;
}
count = text_layout(string, self, dir, features, lang, &glyph_info, mask, color);
if (PyErr_Occurred()) {
return NULL;
}
load_flags = FT_LOAD_DEFAULT;
if (mask) {
load_flags |= FT_LOAD_TARGET_MONO;
}
#ifdef FT_LOAD_COLOR
if (color) {
load_flags |= FT_LOAD_COLOR;
}
#endif
/*
* text bounds are given by:
* - bounding boxes of individual glyphs
* - pen line, i.e. 0 to `advanced` along primary axis
* this means point (0, 0) is part of the text bounding box
*/
face = NULL;
position = x_min = x_max = y_min = y_max = 0;
for (i = 0; i < count; i++) {
face = self->face;
if (horizontal_dir) {
px = PIXEL(position + glyph_info[i].x_offset);
py = PIXEL(glyph_info[i].y_offset);
position += glyph_info[i].x_advance;
advanced = PIXEL(position);
if (advanced > x_max) {
x_max = advanced;
}
} else {
px = PIXEL(glyph_info[i].x_offset);
py = PIXEL(position + glyph_info[i].y_offset);
position += glyph_info[i].y_advance;
advanced = PIXEL(position);
if (advanced < y_min) {
y_min = advanced;
}
}
error = FT_Load_Glyph(face, glyph_info[i].index, load_flags);
if (error) {
return geterror(error);
}
error = FT_Get_Glyph(face->glyph, &glyph);
if (error) {
return geterror(error);
}
FT_Glyph_Get_CBox(glyph, FT_GLYPH_BBOX_PIXELS, &bbox);
bbox.xMax += px;
if (bbox.xMax > x_max) {
x_max = bbox.xMax;
}
bbox.xMin += px;
if (bbox.xMin < x_min) {
x_min = bbox.xMin;
}
bbox.yMax += py;
if (bbox.yMax > y_max) {
y_max = bbox.yMax;
}
bbox.yMin += py;
if (bbox.yMin < y_min) {
y_min = bbox.yMin;
}
FT_Done_Glyph(glyph);
}
if (glyph_info) {
PyMem_Free(glyph_info);
glyph_info = NULL;
}
x_anchor = y_anchor = 0;
if (face) {
if (horizontal_dir) {
switch (anchor[0]) {
case 'l': // left
x_anchor = 0;
break;
case 'm': // middle (left + right) / 2
x_anchor = PIXEL(position / 2);
break;
case 'r': // right
x_anchor = PIXEL(position);
break;
case 's': // vertical baseline
default:
goto bad_anchor;
}
switch (anchor[1]) {
case 'a': // ascender
y_anchor = PIXEL(self->face->size->metrics.ascender);
break;
case 't': // top
y_anchor = y_max;
break;
case 'm': // middle (ascender + descender) / 2
y_anchor = PIXEL(
(self->face->size->metrics.ascender +
self->face->size->metrics.descender) /
2);
break;
case 's': // horizontal baseline
y_anchor = 0;
break;
case 'b': // bottom
y_anchor = y_min;
break;
case 'd': // descender
y_anchor = PIXEL(self->face->size->metrics.descender);
break;
default:
goto bad_anchor;
}
} else {
switch (anchor[0]) {
case 'l': // left
x_anchor = x_min;
break;
case 'm': // middle (left + right) / 2
x_anchor = (x_min + x_max) / 2;
break;
case 'r': // right
x_anchor = x_max;
break;
case 's': // vertical baseline
x_anchor = 0;
break;
default:
goto bad_anchor;
}
switch (anchor[1]) {
case 't': // top
y_anchor = 0;
break;
case 'm': // middle (top + bottom) / 2
y_anchor = PIXEL(position / 2);
break;
case 'b': // bottom
y_anchor = PIXEL(position);
break;
case 'a': // ascender
case 's': // horizontal baseline
case 'd': // descender
default:
goto bad_anchor;
}
}
}
return Py_BuildValue(
"(ii)(ii)",
(x_max - x_min),
(y_max - y_min),
(-x_anchor + x_min),
-(-y_anchor + y_max));
bad_anchor:
PyErr_Format(PyExc_ValueError, "bad anchor specified: %s", anchor);
return NULL;
}
static PyObject *
font_render(FontObject *self, PyObject *args) {
int x, y; /* pen position, in 26.6 precision */
int px, py; /* position of current glyph, in pixels */
int x_min, y_max; /* text offset in 26.6 precision */
int load_flags; /* FreeType load_flags parameter */
int error;
FT_Glyph glyph;
FT_GlyphSlot glyph_slot;
FT_Bitmap bitmap;
FT_Bitmap bitmap_converted; /* initialized lazily, for non-8bpp fonts */
FT_BitmapGlyph bitmap_glyph;
FT_Stroker stroker = NULL;
int bitmap_converted_ready = 0; /* has bitmap_converted been initialized */
GlyphInfo *glyph_info = NULL; /* computed text layout */
size_t i, count; /* glyph_info index and length */
int xx, yy; /* pixel offset of current glyph bitmap */
int x0, x1; /* horizontal bounds of glyph bitmap to copy */
unsigned int bitmap_y; /* glyph bitmap y index */
unsigned char *source; /* glyph bitmap source buffer */
unsigned char convert_scale; /* scale factor for non-8bpp bitmaps */
Imaging im;
Py_ssize_t id;
int mask = 0; /* is FT_LOAD_TARGET_MONO enabled? */
int color = 0; /* is FT_LOAD_COLOR enabled? */
int stroke_width = 0;
PY_LONG_LONG foreground_ink_long = 0;
unsigned int foreground_ink;
const char *mode = NULL;
const char *dir = NULL;
const char *lang = NULL;
PyObject *features = Py_None;
PyObject *string;
/* render string into given buffer (the buffer *must* have
the right size, or this will crash) */
if (!PyArg_ParseTuple(
args,
"On|zzOziL:render",
&string,
&id,
&mode,
&dir,
&features,
&lang,
&stroke_width,
&foreground_ink_long)) {
return NULL;
}
mask = mode && strcmp(mode, "1") == 0;
color = mode && strcmp(mode, "RGBA") == 0;
foreground_ink = foreground_ink_long;
#ifdef FT_COLOR_H
if (color) {
FT_Color foreground_color;
FT_Byte *ink = (FT_Byte *)&foreground_ink;
foreground_color.red = ink[0];
foreground_color.green = ink[1];
foreground_color.blue = ink[2];
foreground_color.alpha =
(FT_Byte)255; /* ink alpha is handled in ImageDraw.text */
FT_Palette_Set_Foreground_Color(self->face, foreground_color);
}
#endif
count = text_layout(string, self, dir, features, lang, &glyph_info, mask, color);
if (PyErr_Occurred()) {
return NULL;
}
if (count == 0) {
Py_RETURN_NONE;
}
if (stroke_width) {
error = FT_Stroker_New(library, &stroker);
if (error) {
return geterror(error);
}
FT_Stroker_Set(
stroker,
(FT_Fixed)stroke_width * 64,
FT_STROKER_LINECAP_ROUND,
FT_STROKER_LINEJOIN_ROUND,
0);
}
im = (Imaging)id;
load_flags = stroke_width ? FT_LOAD_NO_BITMAP : FT_LOAD_DEFAULT;
if (mask) {
load_flags |= FT_LOAD_TARGET_MONO;
}
#ifdef FT_LOAD_COLOR
if (color) {
load_flags |= FT_LOAD_COLOR;
}
#endif
/*
* calculate x_min and y_max
* must match font_getsize or there may be clipping!
*/
x = y = x_min = y_max = 0;
for (i = 0; i < count; i++) {
px = PIXEL(x + glyph_info[i].x_offset);
py = PIXEL(y + glyph_info[i].y_offset);
error =
FT_Load_Glyph(self->face, glyph_info[i].index, load_flags | FT_LOAD_RENDER);
if (error) {
return geterror(error);
}
glyph_slot = self->face->glyph;
bitmap = glyph_slot->bitmap;
if (glyph_slot->bitmap_top + py > y_max) {
y_max = glyph_slot->bitmap_top + py;
}
if (glyph_slot->bitmap_left + px < x_min) {
x_min = glyph_slot->bitmap_left + px;
}
x += glyph_info[i].x_advance;
y += glyph_info[i].y_advance;
}
/* set pen position to text origin */
x = (-x_min + stroke_width) << 6;
y = (-y_max + (-stroke_width)) << 6;
if (stroker == NULL) {
load_flags |= FT_LOAD_RENDER;
}
for (i = 0; i < count; i++) {
px = PIXEL(x + glyph_info[i].x_offset);
py = PIXEL(y + glyph_info[i].y_offset);
error = FT_Load_Glyph(self->face, glyph_info[i].index, load_flags);
if (error) {
return geterror(error);
}
glyph_slot = self->face->glyph;
if (stroker != NULL) {
error = FT_Get_Glyph(glyph_slot, &glyph);
if (!error) {
error = FT_Glyph_Stroke(&glyph, stroker, 1);
}
if (!error) {
FT_Vector origin = {0, 0};
error = FT_Glyph_To_Bitmap(&glyph, FT_RENDER_MODE_NORMAL, &origin, 1);
}
if (error) {
return geterror(error);
}
bitmap_glyph = (FT_BitmapGlyph)glyph;
bitmap = bitmap_glyph->bitmap;
xx = px + bitmap_glyph->left;
yy = -(py + bitmap_glyph->top);
} else {
bitmap = glyph_slot->bitmap;
xx = px + glyph_slot->bitmap_left;
yy = -(py + glyph_slot->bitmap_top);
}
/* convert non-8bpp bitmaps */
switch (bitmap.pixel_mode) {
case FT_PIXEL_MODE_MONO:
convert_scale = 255;
break;
case FT_PIXEL_MODE_GRAY2:
convert_scale = 255 / 3;
break;
case FT_PIXEL_MODE_GRAY4:
convert_scale = 255 / 15;
break;
default:
convert_scale = 1;
}
switch (bitmap.pixel_mode) {
case FT_PIXEL_MODE_MONO:
case FT_PIXEL_MODE_GRAY2:
case FT_PIXEL_MODE_GRAY4:
if (!bitmap_converted_ready) {
FT_Bitmap_Init(&bitmap_converted);
bitmap_converted_ready = 1;
}
error = FT_Bitmap_Convert(library, &bitmap, &bitmap_converted, 1);
if (error) {
geterror(error);
goto glyph_error;
}
bitmap = bitmap_converted;
/* bitmap is now FT_PIXEL_MODE_GRAY, fall through */
case FT_PIXEL_MODE_GRAY:
break;
#ifdef FT_LOAD_COLOR
case FT_PIXEL_MODE_BGRA:
if (color) {
break;
}
/* we didn't ask for color, fall through to default */
#endif
default:
PyErr_SetString(PyExc_IOError, "unsupported bitmap pixel mode");
goto glyph_error;
}
/* clip glyph bitmap width to target image bounds */
x0 = 0;
x1 = bitmap.width;
if (xx < 0) {
x0 = -xx;
}
if (xx + x1 > im->xsize) {
x1 = im->xsize - xx;
}
source = (unsigned char *)bitmap.buffer;
for (bitmap_y = 0; bitmap_y < bitmap.rows; bitmap_y++, yy++) {
/* clip glyph bitmap height to target image bounds */
if (yy >= 0 && yy < im->ysize) {
/* blend this glyph into the buffer */
int k;
unsigned char v;
unsigned char *target;
if (color) {
/* target[RGB] returns the color, target[A] returns the mask */
/* target bands get split again in ImageDraw.text */
target = (unsigned char *)im->image[yy] + xx * 4;
} else {
target = im->image8[yy] + xx;
}
#ifdef FT_LOAD_COLOR
if (color && bitmap.pixel_mode == FT_PIXEL_MODE_BGRA) {
/* paste color glyph */
for (k = x0; k < x1; k++) {
if (target[k * 4 + 3] < source[k * 4 + 3]) {
/* unpremultiply BGRa to RGBA */
target[k * 4 + 0] = CLIP8(
(255 * (int)source[k * 4 + 2]) / source[k * 4 + 3]);
target[k * 4 + 1] = CLIP8(
(255 * (int)source[k * 4 + 1]) / source[k * 4 + 3]);
target[k * 4 + 2] = CLIP8(
(255 * (int)source[k * 4 + 0]) / source[k * 4 + 3]);
target[k * 4 + 3] = source[k * 4 + 3];