BLF: initial word-wrap support

- Adds support for word wrapping to Blender's BLF font library.
- Splits lines when width limit is reached or on explicit \n newlines.

Details:

- Word wrapping is used when `BLF_WORD_WRAP` flag is enabled.
- There is a single loop to handle line wrapping,
  this runs callback, passing in a substring,
  this way we can avoid code-duplication for all word-wrapped
  versions of functions... OR... avoid having to add support
  for word-wrapping directly into each function.
- The `ResultBLF` struct was added to be able to get the number
  of wrapped lines, when calling otherwise unrelated functions
  such as `BLF_draw/BLF_width/BLF_boundbox`,
  which can be passed as the last argument to `BLF_*_ex()` functions.
- The `ResultBLF` struct is used to store the result of drawing
  (currently only the number of lines wrapped, and the width).

source/blender/python/generic/blf_py_api.c

@@ -221,6 +221,29 @@ static PyObject *py_blf_clipping(PyObject *UNUSED(self), PyObject *args)
 	Py_RETURN_NONE;
 }
 
+PyDoc_STRVAR(py_blf_word_wrap_doc,
+".. function:: word_wrap(fontid, wrap_width)\n"
+"\n"
+"   Set the wrap width, enable/disable using WORD_WRAP.\n"
+"\n"
+"   :arg fontid: The id of the typeface as returned by :func:`blf.load`, for default font use 0.\n"
+"   :type fontid: int\n"
+"   :arg wrap_width: The width (in pixels) to wrap words at.\n"
+"   :type wrap_width: int\n"
+);
+static PyObject *py_blf_word_wrap(PyObject *UNUSED(self), PyObject *args)
+{
+	int wrap_width;
+	int fontid;
+
+	if (!PyArg_ParseTuple(args, "ii:blf.word_wrap", &fontid, &wrap_width))
+		return NULL;
+
+	BLF_wordwrap(fontid, wrap_width);
+
+	Py_RETURN_NONE;
+}
+
 PyDoc_STRVAR(py_blf_disable_doc,
 ".. function:: disable(fontid, option)\n"
 "\n"
@@ -393,6 +416,7 @@ static PyMethodDef BLF_methods[] = {
 	{"aspect", (PyCFunction) py_blf_aspect, METH_VARARGS, py_blf_aspect_doc},
 	{"blur", (PyCFunction) py_blf_blur, METH_VARARGS, py_blf_blur_doc},
 	{"clipping", (PyCFunction) py_blf_clipping, METH_VARARGS, py_blf_clipping_doc},
+	{"word_wrap", (PyCFunction) py_blf_word_wrap, METH_VARARGS, py_blf_word_wrap_doc},
 	{"disable", (PyCFunction) py_blf_disable, METH_VARARGS, py_blf_disable_doc},
 	{"dimensions", (PyCFunction) py_blf_dimensions, METH_VARARGS, py_blf_dimensions_doc},
 	{"draw", (PyCFunction) py_blf_draw, METH_VARARGS, py_blf_draw_doc},
@@ -432,6 +456,7 @@ PyObject *BPyInit_blf(void)
 	PyModule_AddIntConstant(submodule, "CLIPPING", BLF_CLIPPING);
 	PyModule_AddIntConstant(submodule, "SHADOW", BLF_SHADOW);
 	PyModule_AddIntConstant(submodule, "KERNING_DEFAULT", BLF_KERNING_DEFAULT);
+	PyModule_AddIntConstant(submodule, "WORD_WRAP", BLF_WORD_WRAP);
 
 	return submodule;
 }