Get variable font data from CoreText

kitty/core_text.m

@@ -22,6 +22,8 @@
 #import <Foundation/NSDictionary.h>
 
 #define debug debug_fonts
+static inline void cleanup_cfrelease(void *__p) { CFTypeRef *tp = (CFTypeRef *)__p; CFTypeRef cf = *tp; if (cf) { CFRelease(cf); } }
+#define RAII_CoreFoundation(type, name, initializer) __attribute__((cleanup(cleanup_cfrelease))) type name = initializer
 
 typedef struct {
     PyObject_HEAD
@@ -35,20 +37,22 @@ typedef struct {
 PyTypeObject CTFace_Type;
 static CTFontRef window_title_font = nil;
 
-static char*
+static PyObject*
 convert_cfstring(CFStringRef src, int free_src) {
-#define SZ 4094
-    static char buf[SZ+2] = {0};
-    bool ok = false;
-    if(!CFStringGetCString(src, buf, SZ, kCFStringEncodingUTF8)) PyErr_SetString(PyExc_ValueError, "Failed to convert CFString");
-    else ok = true;
-    if (free_src) CFRelease(src);
-    return ok ? buf : NULL;
+    RAII_CoreFoundation(CFStringRef, releaseme, free_src ? src : nil);
+    (void)releaseme;
+    if (!src) return PyUnicode_FromString("");
+    const char *fast = CFStringGetCStringPtr(src, kCFStringEncodingUTF8);
+    if (fast) return PyUnicode_FromString(fast);
+#define SZ 4096
+    char buf[SZ];
+    if(!CFStringGetCString(src, buf, SZ, kCFStringEncodingUTF8)) { PyErr_SetString(PyExc_ValueError, "Failed to convert CFString"); return NULL; }
+    return PyUnicode_FromString(buf);
 #undef SZ
 }
 
 static void
-init_face(CTFace *self, CTFontRef font, FONTS_DATA_HANDLE fg UNUSED) {
+init_face(CTFace *self, CTFontRef font) {
     if (self->hb_font) hb_font_destroy(self->hb_font);
     self->hb_font = NULL;
     if (self->ct_font) CFRelease(self->ct_font);
@@ -63,15 +67,15 @@ init_face(CTFace *self, CTFontRef font, FONTS_DATA_HANDLE fg UNUSED) {
 }
 
 static CTFace*
-ct_face(CTFontRef font, FONTS_DATA_HANDLE fg) {
+ct_face(CTFontRef font) {
     CTFace *self = (CTFace *)CTFace_Type.tp_alloc(&CTFace_Type, 0);
     if (self) {
-        init_face(self, font, fg);
-        self->family_name = Py_BuildValue("s", convert_cfstring(CTFontCopyFamilyName(self->ct_font), true));
-        self->full_name = Py_BuildValue("s", convert_cfstring(CTFontCopyFullName(self->ct_font), true));
-        self->postscript_name = Py_BuildValue("s", convert_cfstring(CTFontCopyPostScriptName(self->ct_font), true));
+        init_face(self, font);
+        self->family_name = convert_cfstring(CTFontCopyFamilyName(self->ct_font), true);
+        self->full_name = convert_cfstring(CTFontCopyFullName(self->ct_font), true);
+        self->postscript_name = convert_cfstring(CTFontCopyPostScriptName(self->ct_font), true);
         NSURL *url = (NSURL*)CTFontCopyAttribute(self->ct_font, kCTFontURLAttribute);
-        self->path = Py_BuildValue("s", [[url path] UTF8String]);
+        self->path = PyUnicode_FromString([[url path] UTF8String]);
         [url release];
         if (self->family_name == NULL || self->full_name == NULL || self->postscript_name == NULL || self->path == NULL) { Py_CLEAR(self); }
     }
@@ -323,7 +327,7 @@ apply_styles_to_fallback_font(CTFontRef original_fallback_font, bool bold, bool
 PyObject*
 create_fallback_face(PyObject *base_face, CPUCell* cell, bool bold, bool italic, bool emoji_presentation, FONTS_DATA_HANDLE fg) {
     CTFace *self = (CTFace*)base_face;
-    CTFontRef new_font;
+    RAII_CoreFoundation(CTFontRef, new_font, NULL);
 #define search_for_fallback() \
         char text[64] = {0}; \
         cell_as_utf8_for_fallback(cell, text); \
@@ -341,7 +345,8 @@ create_fallback_face(PyObject *base_face, CPUCell* cell, bool bold, bool italic,
     }
     else { search_for_fallback(); new_font = apply_styles_to_fallback_font(new_font, bold, italic); }
     if (new_font == NULL) return NULL;
-    PyObject *postscript_name = Py_BuildValue("s", convert_cfstring(CTFontCopyPostScriptName(new_font), true));
+    RAII_PyObject(postscript_name, convert_cfstring(CTFontCopyPostScriptName(new_font), true));
+    if (!postscript_name) return NULL;
     ssize_t idx = -1;
     PyObject *q, *ans = NULL;
     while ((q = iter_fallback_faces(fg, &idx))) {
@@ -351,10 +356,7 @@ create_fallback_face(PyObject *base_face, CPUCell* cell, bool bold, bool italic,
             break;
         }
     }
-    Py_CLEAR(postscript_name);
-    if (ans == NULL) return (PyObject*)ct_face(new_font, fg);
-    CFRelease(new_font);
-    return ans;
+    return ans ? ans : (PyObject*)ct_face(new_font);
 }
 
 unsigned int
@@ -393,7 +395,7 @@ set_size_for_face(PyObject *s, unsigned int UNUSED desired_height, bool force, F
     if (!force && self->scaled_point_sz == sz) return true;
     CTFontRef new_font = CTFontCreateCopyWithAttributes(self->ct_font, sz, NULL, NULL);
     if (new_font == NULL) fatal("Out of memory");
-    init_face(self, new_font, fg);
+    init_face(self, new_font);
     return true;
 }
 
@@ -479,21 +481,34 @@ PyObject*
 face_from_descriptor(PyObject *descriptor, FONTS_DATA_HANDLE fg) {
     CTFontDescriptorRef desc = font_descriptor_from_python(descriptor);
     if (!desc) return NULL;
-    CTFontRef font = CTFontCreateWithFontDescriptor(desc, scaled_point_sz(fg), NULL);
+    CTFontRef font = CTFontCreateWithFontDescriptor(desc, fg ? scaled_point_sz(fg) : 12, NULL);
     CFRelease(desc); desc = NULL;
     if (!font) { PyErr_SetString(PyExc_ValueError, "Failed to create CTFont object"); return NULL; }
-    return (PyObject*) ct_face(font, fg);
+    return (PyObject*) ct_face(font);
 }
 
 PyObject*
-face_from_path(const char *path, int UNUSED index, FONTS_DATA_HANDLE fg) {
+face_from_path(const char *path, int UNUSED index, FONTS_DATA_HANDLE fg UNUSED) {
     CFStringRef s = CFStringCreateWithCString(NULL, path, kCFStringEncodingUTF8);
     CFURLRef url = CFURLCreateWithFileSystemPath(kCFAllocatorDefault, s, kCFURLPOSIXPathStyle, false);
     CGDataProviderRef dp = CGDataProviderCreateWithURL(url);
     CGFontRef cg_font = CGFontCreateWithDataProvider(dp);
     CTFontRef ct_font = CTFontCreateWithGraphicsFont(cg_font, 0.0, NULL, NULL);
     CFRelease(cg_font); CFRelease(dp); CFRelease(url); CFRelease(s);
-    return (PyObject*) ct_face(ct_font, fg);
+    return (PyObject*) ct_face(ct_font);
+}
+
+static PyObject*
+new(PyTypeObject *type UNUSED, PyObject *args, PyObject *kw) {
+    const char *path = NULL;
+    PyObject *descriptor = NULL;
+
+    static char *kwds[] = {"descriptor", "path", NULL};
+    if (!PyArg_ParseTupleAndKeywords(args, kw, "|Os", kwds, &descriptor, &path)) return NULL;
+    if (descriptor) return face_from_descriptor(descriptor, NULL);
+    if (path) return face_from_path(path, 0, NULL);
+    PyErr_SetString(PyExc_TypeError, "Must specify either path or descriptor");
+    return NULL;
 }
 
 PyObject*
@@ -760,12 +775,84 @@ render_glyphs_in_cells(PyObject *s, bool bold, bool italic, hb_glyph_info_t *inf
 static PyObject*
 display_name(CTFace *self) {
     CFStringRef dn = CTFontCopyDisplayName(self->ct_font);
-    const char *d = convert_cfstring(dn, true);
-    return Py_BuildValue("s", d);
+    return convert_cfstring(dn, true);
+}
+
+static const char*
+tag_to_string(uint32_t tag, uint8_t bytes[5]) {
+    bytes[0] = (tag >> 24) & 0xff;
+    bytes[1] = (tag >> 16) & 0xff;
+    bytes[2] = (tag >> 8) & 0xff;
+    bytes[3] = (tag) & 0xff;
+    bytes[4] = 0;
+    return (const char*)bytes;
+}
+
+static void
+convert_variation_to_python(const void *key, const void *value_, void *axis_values) {
+    unsigned long tag; float value;
+    CFNumberGetValue(key, kCFNumberLongType, &tag);
+    CFNumberGetValue(value_, kCFNumberFloatType, &value);
+    uint8_t tag_buf[5] = {0};
+    RAII_PyObject(val, PyFloat_FromDouble((double)value));
+    if (val) PyDict_SetItemString(axis_values, tag_to_string(tag, tag_buf), val);
+}
+
+static PyObject*
+get_variable_data(CTFace *self) {
+    uint8_t tag_buf[5] = {0};
+    RAII_CoreFoundation(CFArrayRef, cfaxes, CTFontCopyVariationAxes(self->ct_font));
+    RAII_PyObject(axes, PyTuple_New(CFArrayGetCount(cfaxes)));
+    for (CFIndex i = 0; i < CFArrayGetCount(cfaxes); i++) {
+        CFDictionaryRef a = (CFDictionaryRef)CFArrayGetValueAtIndex(cfaxes, i);
+#define get_number(key, output, type, optional) { \
+            CFNumberRef value = (CFNumberRef)CFDictionaryGetValue(a, key); \
+            if (value) CFNumberGetValue(value, type, &output); \
+            else if (!optional) { PyErr_Format(PyExc_RuntimeError, "The %s key was not present in the varioation axis dictionary", #key); return NULL; } \
+}
+        float minimum = 0, maximum = 0, def = 0; unsigned long tag = 0, hidden = 0;
+        get_number(kCTFontVariationAxisDefaultValueKey, def, kCFNumberFloatType, false);
+        get_number(kCTFontVariationAxisMaximumValueKey, maximum, kCFNumberFloatType, false);
+        get_number(kCTFontVariationAxisMinimumValueKey, minimum, kCFNumberFloatType, false);
+        get_number(kCTFontVariationAxisIdentifierKey, tag, kCFNumberLongType, false);
+        get_number(kCTFontVariationAxisHiddenKey, hidden, kCFNumberLongType, true);
+#undef get_number
+        CFStringRef n = (CFStringRef)CFDictionaryGetValue(a, kCTFontVariationAxisNameKey);
+        PyObject *axis = Py_BuildValue("{sd sd sd ss sO sO}",
+            "minimum", minimum, "maximum", maximum, "default", def, "tag", tag_to_string(tag, tag_buf),
+            "hidden", hidden ? Py_True : Py_False, "strid", convert_cfstring(n, false)
+        );
+        if (!axis) return NULL;
+        PyTuple_SET_ITEM(axes, i, axis);
+    }
+    RAII_CoreFoundation(CFStringRef, font_family_name, CTFontCopyFamilyName(self->ct_font));
+    RAII_CoreFoundation(CTFontDescriptorRef, descriptor,
+            CTFontDescriptorCreateWithAttributes((__bridge CFDictionaryRef)@{(id)kCTFontFamilyNameAttribute: (__bridge NSString*)font_family_name}));
+    RAII_CoreFoundation(CTFontCollectionRef, collection,
+            CTFontCollectionCreateWithFontDescriptors((__bridge CFArrayRef)@[(__bridge id)descriptor], NULL));
+    RAII_CoreFoundation(CFArrayRef, descriptors, CTFontCollectionCreateMatchingFontDescriptors(collection));
+    RAII_PyObject(named_styles, PyTuple_New(CFArrayGetCount(descriptors)));
+    Py_ssize_t actual_num = 0;
+    for (CFIndex i = 0; i < CFArrayGetCount(descriptors); i++) {
+        CTFontDescriptorRef descriptor = (CTFontDescriptorRef)CFArrayGetValueAtIndex(descriptors, i);
+        RAII_CoreFoundation(CFDictionaryRef, variation, CTFontDescriptorCopyAttribute(descriptor, kCTFontVariationAttribute));
+        if (!variation) continue;
+        RAII_CoreFoundation(CFStringRef, style, CTFontDescriptorCopyAttribute(descriptor, kCTFontStyleNameAttribute));
+        RAII_CoreFoundation(CFStringRef, psname, CTFontDescriptorCopyAttribute(descriptor, kCTFontNameAttribute));
+        RAII_PyObject(axis_values, PyDict_New());
+        if (!axis_values) return NULL;
+        CFDictionaryApplyFunction(variation, convert_variation_to_python, axis_values);
+        PyObject *ns = Py_BuildValue("{sO sN sN}", "axis_values", axis_values, "name", convert_cfstring(style, false), "psname", convert_cfstring(psname, false));
+        if (!ns) return NULL;
+        PyTuple_SET_ITEM(named_styles, actual_num, ns); actual_num++;
+    }
+    _PyTuple_Resize(&named_styles, actual_num);
+    return Py_BuildValue("{sO sO}", "axes", axes, "named_styles", named_styles); //, "named_styles", named_styles);
 }
 
 static PyMethodDef methods[] = {
     METHODB(display_name, METH_NOARGS),
+    METHODB(get_variable_data, METH_NOARGS),
     {NULL}  /* Sentinel */
 };
 
@@ -813,6 +900,7 @@ static PyMemberDef members[] = {
 PyTypeObject CTFace_Type = {
     PyVarObject_HEAD_INIT(NULL, 0)
     .tp_name = "fast_data_types.CTFace",
+    .tp_new = new,
     .tp_basicsize = sizeof(CTFace),
     .tp_dealloc = (destructor)dealloc,
     .tp_flags = Py_TPFLAGS_DEFAULT,

kitty/fast_data_types.pyi

@@ -440,6 +440,11 @@ class CoreTextFont(TypedDict):
     traits: int
 
 
+class CTFace:
+    def __init__(self, descriptor: Optional[CoreTextFont] = None, path: str = ''): ...
+    def get_variable_data(self) -> VariableData: ...
+
+
 def coretext_all_fonts() -> Tuple[CoreTextFont, ...]:
     pass
 

kitty/fonts/__init__.py

@@ -1,5 +1,5 @@
 from enum import Enum, IntEnum, auto
-from typing import NamedTuple, Optional, Tuple, TypedDict, Union
+from typing import Dict, NamedTuple, Optional, Tuple, TypedDict, Union
 
 from kitty.typing import CoreTextFont, FontConfigPattern
 
@@ -19,11 +19,11 @@ class VariableAxis(TypedDict):
     default: float
     hidden: bool
     tag: str
-    strid: Optional[str]
+    strid: str  # Can be empty string when not present
 
 
 class NamedStyle(TypedDict):
-    axis_values: Tuple[float, ...]
+    axis_values: Dict[str, float]
     name: Optional[str]
     psname: Optional[str]
 

kitty/fonts/core_text.py

@@ -4,7 +4,7 @@
 import re
 from typing import Dict, Generator, Iterable, List, Optional, Tuple
 
-from kitty.fast_data_types import coretext_all_fonts
+from kitty.fast_data_types import CTFace, coretext_all_fonts
 from kitty.fonts import FontFeature, VariableData
 from kitty.options.types import Options
 from kitty.typing import CoreTextFont
@@ -120,4 +120,4 @@ def font_for_family(family: str) -> Tuple[CoreTextFont, bool, bool]:
 def get_variable_data_for_descriptor(f: ListedFont) -> VariableData:
     d = f['descriptor']
     assert d['descriptor_type'] == 'core_text'
-    return d['variable_data']
+    return CTFace(descriptor=d).get_variable_data()

kitty/fonts/list.py

@@ -76,8 +76,8 @@ def show_variable(f: ListedFont, psnames: bool) -> None:
             if psnames:
                 name += f' ({ns["psname"] or ""})'
             axes = []
-            for axis, val in zip(vd['axes'], ns['axis_values']):
-                axes.append(f'{axis["tag"]}={val:g}')
+            for axis_tag, val in ns['axis_values'].items():
+                axes.append(f'{axis_tag}={val:g}')
             p = name + ': ' + ' '.join(axes)
             print(indented(p, level=3))
 

kitty/freetype.c

@@ -787,15 +787,26 @@ static inline void cleanup_ftmm(FT_MM_Var **p) { if (*p) FT_Done_MM_Var(library,
 
 #define RAII_FTMMVar(name) __attribute__((cleanup(cleanup_ftmm))) FT_MM_Var *name = NULL
 
+static const char*
+tag_to_string(uint32_t tag, uint8_t bytes[5]) {
+    bytes[0] = (tag >> 24) & 0xff;
+    bytes[1] = (tag >> 16) & 0xff;
+    bytes[2] = (tag >> 8) & 0xff;
+    bytes[3] = (tag) & 0xff;
+    bytes[4] = 0;
+    return (const char*)bytes;
+}
+
 static PyObject*
-convert_named_style_to_python(Face *face, const FT_Var_Named_Style *src, unsigned num_of_axes) {
-    RAII_PyObject(axis_values, PyTuple_New(num_of_axes));
+convert_named_style_to_python(Face *face, const FT_Var_Named_Style *src, FT_Var_Axis *axes, unsigned num_of_axes) {
+    RAII_PyObject(axis_values, PyDict_New());
     if (!axis_values) return NULL;
+    uint8_t tag_buf[5] = {0};
     for (FT_UInt i = 0; i < num_of_axes; i++) {
         double val = src->coords[i] / 65536.0;
-        PyObject *pval = PyFloat_FromDouble(val);
+        RAII_PyObject(pval, PyFloat_FromDouble(val));
         if (!pval) return NULL;
-        PyTuple_SET_ITEM(axis_values, i, pval);
+        if (PyDict_SetItemString(axis_values, tag_to_string(axes[i].tag, tag_buf), pval) != 0) return NULL;
     }
     RAII_PyObject(name, _get_best_name(face, src->strid));
     if (!name) PyErr_Clear();
@@ -804,25 +815,15 @@ convert_named_style_to_python(Face *face, const FT_Var_Named_Style *src, unsigne
     return Py_BuildValue("{sO sO sO}", "axis_values", axis_values, "name", name ? name : Py_None, "psname", psname ? psname : Py_None);
 }
 
-static PyObject*
-tag_to_string(uint32_t tag) {
-    if (!tag) return PyUnicode_FromString("");
-    unsigned char bytes[5] = {0};
-    bytes[0] = (tag >> 24) & 0xff;
-    bytes[1] = (tag >> 16) & 0xff;
-    bytes[2] = (tag >> 8) & 0xff;
-    bytes[3] = (tag) & 0xff;
-    return PyUnicode_DecodeASCII((const char*)bytes, 4, "replace");
-}
-
 static PyObject*
 convert_axis_to_python(Face *face, const FT_Var_Axis *src, FT_UInt flags) {
-    RAII_PyObject(strid, _get_best_name(face, src->strid));
-    if (!strid) PyErr_Clear();
-    return Py_BuildValue("{sd sd sd sO ss sN sO}",
+    PyObject *strid = _get_best_name(face, src->strid);
+    if (!strid) { PyErr_Clear(); strid = PyUnicode_FromString(""); }
+    uint8_t tag_buf[5] = {0};
+    return Py_BuildValue("{sd sd sd sO ss ss sN}",
         "minimum", src->minimum / 65536.0, "maximum", src->maximum / 65536.0, "default", src->def / 65536.0,
-        "hidden", flags & FT_VAR_AXIS_FLAG_HIDDEN ? Py_True : Py_False, "name", src->name, "tag", tag_to_string(src->tag),
-        "strid", strid ? strid : Py_None
+        "hidden", flags & FT_VAR_AXIS_FLAG_HIDDEN ? Py_True : Py_False, "name", src->name, "tag", tag_to_string(src->tag, tag_buf),
+        "strid", strid
     );
 }
 
@@ -835,7 +836,7 @@ get_variable_data(Face *self, PyObject *a UNUSED) {
     RAII_PyObject(named_styles, PyTuple_New(mm->num_namedstyles));
     if (!axes || !named_styles) return NULL;
     for (FT_UInt i = 0; i < mm->num_namedstyles; i++) {
-        PyObject *s = convert_named_style_to_python(self, mm->namedstyle + i, mm->num_axis);
+        PyObject *s = convert_named_style_to_python(self, mm->namedstyle + i, mm->axis, mm->num_axis);
         if (!s) return NULL;
         PyTuple_SET_ITEM(named_styles, i, s);
     }