Work on rendering sample text for a font

kittens/choose_fonts/backend.py

@@ -2,11 +2,16 @@
 # License: GPLv3 Copyright: 2024, Kovid Goyal <kovid at kovidgoyal.net>
 
 import json
+import string
 import sys
-from typing import Any
+from typing import Any, Dict, Tuple, TypedDict
 
-from kitty.fonts.common import get_variable_data_for_descriptor
+from kitty.conf.utils import to_color
+from kitty.fonts import Descriptor
+from kitty.fonts.common import face_from_descriptor, get_font_files, get_variable_data_for_descriptor
 from kitty.fonts.list import create_family_groups
+from kitty.options.types import Options
+from kitty.options.utils import parse_font_spec
 
 
 def send_to_kitten(x: Any) -> None:
@@ -15,7 +20,77 @@ def send_to_kitten(x: Any) -> None:
     sys.stdout.buffer.flush()
 
 
+class TextStyle(TypedDict):
+    font_size: float
+    dpi_x: float
+    dpi_y: float
+    foreground: str
+    background: str
+
+
+FamilyKey = Tuple[str, ...]
+
+
+def opts_from_cmd(cmd: Dict[str, Any]) -> Tuple[Options, FamilyKey, float, float]:
+    opts = Options()
+    ts: TextStyle = cmd['text_style']
+    opts.font_size = ts['font_size']
+    opts.foreground = to_color(ts['foreground'])
+    opts.background = to_color(ts['background'])
+    family_key = []
+    if 'font_family' in cmd:
+        opts.font_family = parse_font_spec(cmd['font_family'])
+        family_key.append(cmd['font_family'])
+    if 'bold_font' in cmd:
+        opts.bold_font = parse_font_spec(cmd['bold_font'])
+        family_key.append(cmd['bold_font'])
+    if 'italic_font' in cmd:
+        opts.italic_font = parse_font_spec(cmd['italic_font'])
+        family_key.append(cmd['italic_font'])
+    if 'bold_italic_font' in cmd:
+        opts.bold_italic_font = parse_font_spec(cmd['bold_italic_font'])
+        family_key.append(cmd['bold_italic_font'])
+    return opts, tuple(family_key), ts['dpi_x'], ts['dpi_y']
+
+
+BaseKey = Tuple[FamilyKey, int, int]
+FaceKey = Tuple[str, BaseKey]
+SAMPLE_TEXT = string.ascii_lowercase + string.digits + string.ascii_uppercase + ' ' + string.punctuation
+
+
+def render_face_sample(font: Descriptor, opts: Options, dpi_x: float, dpi_y: float, width: int, height: int, output_dir: str) -> str:
+    face = face_from_descriptor(font)
+    face.set_size(opts.font_size, dpi_x, dpi_y)
+    face.render_sample_text(SAMPLE_TEXT, width, height, opts.foreground.rgb)
+
+
+def render_family_sample(
+    opts: Options, family_key: FamilyKey, dpi_x: float, dpi_y: float, width: int, height: int, output_dir: str,
+    cache: Dict[FaceKey, str]
+) -> Dict[str, str]:
+    base_key: BaseKey = family_key, width, height
+    ans: Dict[str, str] = {}
+    font_files = get_font_files(opts)
+    for x in family_key:
+        key: FaceKey = x, base_key
+        if x == 'font_family':
+            desc = font_files['medium']
+        elif x == 'bold_font':
+            desc = font_files['bold']
+        elif x == 'italic_font':
+            desc = font_files['italic']
+        elif x == 'bold_italic_font':
+            desc = font_files['bi']
+        cached = cache.get(key)
+        if cached is not None:
+            ans[x] = cached
+        else:
+            cache[key] = ans[x] = render_face_sample(desc, opts, dpi_x, dpi_y, width, height, output_dir)
+    return ans
+
+
 def main() -> None:
+    cache: Dict[FaceKey, str] = {}
     for line in sys.stdin.buffer:
         cmd = json.loads(line)
         action = cmd.get('action', '')
@@ -26,5 +101,8 @@ def main() -> None:
             for descriptor in cmd['descriptors']:
                 ans.append(get_variable_data_for_descriptor(descriptor))
             send_to_kitten(ans)
+        elif action == 'render_family_samples':
+            opts, family_key, dpi_x, dpi_y = opts_from_cmd(cmd)
+            send_to_kitten(render_family_sample(opts, family_key, dpi_x, dpi_y, cmd['width'], cmd['height'], cmd['output_dir'], cache))
         else:
             raise SystemExit(f'Unknown action: {action}')

kittens/choose_fonts/ui.go

@@ -24,6 +24,14 @@ const (
 	CHOOSING_FACES
 )
 
+type TextStyle struct {
+	Font_sz    float64 `json:"font_size"`
+	Dpi_x      float64 `json:"dpi_x"`
+	Dpi_y      float64 `json:"dpi_y"`
+	Foreground string  `json:"foreground"`
+	Background string  `json:"background"`
+}
+
 type handler struct {
 	lp                   *loop.Loop
 	fonts                map[string][]ListedFont
@@ -33,10 +41,7 @@ type handler struct {
 	mouse_state          tui.MouseState
 	render_count         uint
 	render_lines         tui.RenderLines
-	text_style           struct {
-		font_sz, dpi_x, dpi_y  float64
-		foreground, background string
-	}
+	text_style           TextStyle
 
 	// Listing
 	rl                          *readline.Readline
@@ -295,21 +300,21 @@ func (h *handler) on_query_response(key, val string, valid bool) error {
 	}
 	switch key {
 	case "font_size":
-		if err := set_float(key, val, &h.text_style.font_sz); err != nil {
+		if err := set_float(key, val, &h.text_style.Font_sz); err != nil {
 			return err
 		}
 	case "dpi_x":
-		if err := set_float(key, val, &h.text_style.dpi_x); err != nil {
+		if err := set_float(key, val, &h.text_style.Dpi_x); err != nil {
 			return err
 		}
 	case "dpi_y":
-		if err := set_float(key, val, &h.text_style.dpi_y); err != nil {
+		if err := set_float(key, val, &h.text_style.Dpi_y); err != nil {
 			return err
 		}
 	case "foreground":
-		h.text_style.foreground = val
+		h.text_style.Foreground = val
 	case "background":
-		h.text_style.background = val
+		h.text_style.Background = val
 	}
 	return nil
 }