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Merged
QuLogic merged 1 commit into from
May 29, 2025
Merged

Simplify/improve error reporting from ft2font. #30102

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108 changes: 27 additions & 81 deletions src/ft2font.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -43,26 +43,6 @@

FT_Library _ft2Library;

// FreeType error codes; loaded as per fterror.h.
static char const* ft_error_string(FT_Error error) {
#undef __FTERRORS_H__
#define FT_ERROR_START_LIST switch (error) {
#define FT_ERRORDEF( e, v, s ) case v: return s;
#define FT_ERROR_END_LIST default: return NULL; }
#include FT_ERRORS_H
}

void throw_ft_error(std::string message, FT_Error error) {
char const* s = ft_error_string(error);
std::ostringstream os("");
if (s) {
os << message << " (" << s << "; error code 0x" << std::hex << error << ")";
} else { // Should not occur, but don't add another error from failed lookup.
os << message << " (error code 0x" << std::hex << error << ")";
}
throw std::runtime_error(os.str());
}

FT2Image::FT2Image(unsigned long width, unsigned long height)
: m_buffer((unsigned char *)calloc(width * height, 1)), m_width(width), m_height(height)
{
Expand Down Expand Up @@ -237,26 +217,16 @@ FT2Font::FT2Font(FT_Open_Args &open_args,
kerning_factor(0)
{
clear();

FT_Error error = FT_Open_Face(_ft2Library, &open_args, 0, &face);
if (error) {
throw_ft_error("Can not load face", error);
}

// set a default fontsize 12 pt at 72dpi
error = FT_Set_Char_Size(face, 12 * 64, 0, 72 * (unsigned int)hinting_factor, 72);
if (error) {
FT_Done_Face(face);
throw_ft_error("Could not set the fontsize", error);
}

FT_CHECK(FT_Open_Face, _ft2Library, &open_args, 0, &face);
if (open_args.stream != nullptr) {
face->face_flags |= FT_FACE_FLAG_EXTERNAL_STREAM;
}

FT_Matrix transform = { 65536 / hinting_factor, 0, 0, 65536 };
FT_Set_Transform(face, &transform, nullptr);

try {
set_size(12., 72.); // Set a default fontsize 12 pt at 72dpi.
} catch (...) {
FT_Done_Face(face);
throw;
}
// Set fallbacks
std::copy(fallback_list.begin(), fallback_list.end(), std::back_inserter(fallbacks));
}
Expand Down Expand Up @@ -293,11 +263,9 @@ void FT2Font::clear()

void FT2Font::set_size(double ptsize, double dpi)
{
FT_Error error = FT_Set_Char_Size(
FT_CHECK(
FT_Set_Char_Size,
face, (FT_F26Dot6)(ptsize * 64), 0, (FT_UInt)(dpi * hinting_factor), (FT_UInt)dpi);
if (error) {
throw_ft_error("Could not set the fontsize", error);
}
FT_Matrix transform = { 65536 / hinting_factor, 0, 0, 65536 };
FT_Set_Transform(face, &transform, nullptr);

Expand All @@ -311,17 +279,12 @@ void FT2Font::set_charmap(int i)
if (i >= face->num_charmaps) {
throw std::runtime_error("i exceeds the available number of char maps");
}
FT_CharMap charmap = face->charmaps[i];
if (FT_Error error = FT_Set_Charmap(face, charmap)) {
throw_ft_error("Could not set the charmap", error);
}
FT_CHECK(FT_Set_Charmap, face, face->charmaps[i]);
}

void FT2Font::select_charmap(unsigned long i)
{
if (FT_Error error = FT_Select_Charmap(face, (FT_Encoding)i)) {
throw_ft_error("Could not set the charmap", error);
}
FT_CHECK(FT_Select_Charmap, face, (FT_Encoding)i);
}

int FT2Font::get_kerning(FT_UInt left, FT_UInt right, FT_Kerning_Mode mode,
Expand Down Expand Up @@ -477,10 +440,10 @@ void FT2Font::load_char(long charcode, FT_Int32 flags, FT2Font *&ft_object, bool
if (!was_found) {
ft_glyph_warn(charcode, glyph_seen_fonts);
if (charcode_error) {
throw_ft_error("Could not load charcode", charcode_error);
THROW_FT_ERROR("charcode loading", charcode_error);
}
else if (glyph_error) {
throw_ft_error("Could not load charcode", glyph_error);
THROW_FT_ERROR("charcode loading", glyph_error);
}
} else if (ft_object_with_glyph->warn_if_used) {
ft_glyph_warn(charcode, glyph_seen_fonts);
Expand All @@ -494,13 +457,9 @@ void FT2Font::load_char(long charcode, FT_Int32 flags, FT2Font *&ft_object, bool
glyph_seen_fonts.insert((face != nullptr)?face->family_name: nullptr);
ft_glyph_warn((FT_ULong)charcode, glyph_seen_fonts);
}
if (FT_Error error = FT_Load_Glyph(face, glyph_index, flags)) {
throw_ft_error("Could not load charcode", error);
}
FT_CHECK(FT_Load_Glyph, face, glyph_index, flags);
FT_Glyph thisGlyph;
if (FT_Error error = FT_Get_Glyph(face->glyph, &thisGlyph)) {
throw_ft_error("Could not get glyph", error);
}
FT_CHECK(FT_Get_Glyph, face->glyph, &thisGlyph);
glyphs.push_back(thisGlyph);
}
}
Expand Down Expand Up @@ -600,13 +559,9 @@ void FT2Font::load_glyph(FT_UInt glyph_index,

void FT2Font::load_glyph(FT_UInt glyph_index, FT_Int32 flags)
{
if (FT_Error error = FT_Load_Glyph(face, glyph_index, flags)) {
throw_ft_error("Could not load glyph", error);
}
FT_CHECK(FT_Load_Glyph, face, glyph_index, flags);
FT_Glyph thisGlyph;
if (FT_Error error = FT_Get_Glyph(face->glyph, &thisGlyph)) {
throw_ft_error("Could not get glyph", error);
}
FT_CHECK(FT_Get_Glyph, face->glyph, &thisGlyph);
glyphs.push_back(thisGlyph);
}

Expand Down Expand Up @@ -651,13 +606,10 @@ void FT2Font::draw_glyphs_to_bitmap(bool antialiased)
image = py::array_t<uint8_t>{{height, width}};
std::memset(image.mutable_data(0), 0, image.nbytes());

for (auto & glyph : glyphs) {
FT_Error error = FT_Glyph_To_Bitmap(
for (auto & glyph: glyphs) {
FT_CHECK(
FT_Glyph_To_Bitmap,
&glyph, antialiased ? FT_RENDER_MODE_NORMAL : FT_RENDER_MODE_MONO, nullptr, 1);
if (error) {
throw_ft_error("Could not convert glyph to bitmap", error);
}

FT_BitmapGlyph bitmap = (FT_BitmapGlyph)glyph;
// now, draw to our target surface (convert position)

Expand All @@ -681,16 +633,12 @@ void FT2Font::draw_glyph_to_bitmap(
throw std::runtime_error("glyph num is out of range");
}

FT_Error error = FT_Glyph_To_Bitmap(
&glyphs[glyphInd],
antialiased ? FT_RENDER_MODE_NORMAL : FT_RENDER_MODE_MONO,
&sub_offset, // additional translation
1 // destroy image
);
if (error) {
throw_ft_error("Could not convert glyph to bitmap", error);
}

FT_CHECK(
FT_Glyph_To_Bitmap,
&glyphs[glyphInd],
antialiased ? FT_RENDER_MODE_NORMAL : FT_RENDER_MODE_MONO,
&sub_offset, // additional translation
1); // destroy image
FT_BitmapGlyph bitmap = (FT_BitmapGlyph)glyphs[glyphInd];

draw_bitmap(im, &bitmap->bitmap, x + bitmap->left, y);
Expand All @@ -715,9 +663,7 @@ void FT2Font::get_glyph_name(unsigned int glyph_number, std::string &buffer,
throw std::runtime_error("Failed to convert glyph to standard name");
}
} else {
if (FT_Error error = FT_Get_Glyph_Name(face, glyph_number, buffer.data(), buffer.size())) {
throw_ft_error("Could not get glyph names", error);
}
FT_CHECK(FT_Get_Glyph_Name, face, glyph_number, buffer.data(), buffer.size());
auto len = buffer.find('\0');
if (len != buffer.npos) {
buffer.resize(len);
Expand Down
31 changes: 28 additions & 3 deletions src/ft2font.h
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -6,6 +6,7 @@
#ifndef MPL_FT2FONT_H
#define MPL_FT2FONT_H

#include <filesystem>
#include <set>
#include <string>
#include <string_view>
Expand All @@ -26,12 +27,36 @@ extern "C" {
#include <pybind11/numpy.h>
namespace py = pybind11;

/*
By definition, FT_FIXED as 2 16bit values stored in a single long.
*/
// By definition, FT_FIXED as 2 16bit values stored in a single long.
#define FIXED_MAJOR(val) (signed short)((val & 0xffff0000) >> 16)
#define FIXED_MINOR(val) (unsigned short)(val & 0xffff)

// Error handling (error codes are loaded as described in fterror.h).
inline char const* ft_error_string(FT_Error error) {
#undef __FTERRORS_H__
#define FT_ERROR_START_LIST switch (error) {
#define FT_ERRORDEF( e, v, s ) case v: return s;
#define FT_ERROR_END_LIST default: return NULL; }
#include FT_ERRORS_H
}

// No more than 16 hex digits + "0x" + null byte for a 64-bit int error.
#define THROW_FT_ERROR(name, err) { \
char buf[20] = {0}; \
sprintf(buf, "%#04x", err); \
throw std::runtime_error{ \
name " (" \
+ std::filesystem::path(__FILE__).filename().string() \
+ " line " + std::to_string(__LINE__) + ") failed with error " \
+ std::string{buf} + ": " + std::string{ft_error_string(err)}}; \
} (void)0

#define FT_CHECK(func, ...) { \
if (auto const& error_ = func(__VA_ARGS__)) { \
THROW_FT_ERROR(#func, error_); \
} \
} (void)0

// the FreeType string rendered into a width, height buffer
class FT2Image
{
Expand Down