fix radio value

Author: codehz

index.html

@@ -357,7 +357,7 @@
 const formatstring = form.elements.formatstring.value;
 const gridsize = form.elements.gridsize.value;
 const glyph_sizes_bin = form.elements.glyph_sizes_bin.value;
-const metamode = form.elements.metamode.value ? getRadio(form.elements.metamode);
+const metamode = form.elements.metamode.value || getRadio(form.elements.metamode);
 const pack_format = parseInt(form.elements.pack_format.value);
 const description_format = form.elements.description_format.value;
 preview_canvas.width = gridsize * 16;