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).

1 files changed, 11 insertions, 7 deletions

diff --git a/source/blender/blenfont/intern/blf_internal.h b/source/blender/blenfont/intern/blf_internal.h
index 85410a4d856..55bc61e0e43 100644
--- a/source/blender/blenfont/intern/blf_internal.h
+++ b/source/blender/blenfont/intern/blf_internal.h
@@ -31,6 +31,7 @@
 #ifndef __BLF_INTERNAL_H__
 #define __BLF_INTERNAL_H__
 
+struct ResultBLF;
 struct FontBLF;
 struct GlyphBLF;
 struct GlyphCacheBLF;
@@ -51,16 +52,19 @@ struct FontBLF *blf_font_new_from_mem(const char *name, const unsigned char *mem
 void blf_font_attach_from_mem(struct FontBLF *font, const unsigned char *mem, int mem_size);
 
 void blf_font_size(struct FontBLF *font, unsigned int size, unsigned int dpi);
-void blf_font_draw(struct FontBLF *font, const char *str, size_t len);
-void blf_font_draw_ascii(struct FontBLF *font, const char *str, size_t len);
+void blf_font_draw(struct FontBLF *font, const char *str, size_t len, struct ResultBLF *r_info);
+void blf_font_draw__wrap(struct FontBLF *font, const char *str, size_t len, struct ResultBLF *r_info);
+void blf_font_draw_ascii(struct FontBLF *font, const char *str, size_t len, struct ResultBLF *r_info);
 int blf_font_draw_mono(struct FontBLF *font, const char *str, size_t len, int cwidth);
-void blf_font_buffer(struct FontBLF *font, const char *str);
+void blf_font_draw_buffer(struct FontBLF *font, const char *str, size_t len, struct ResultBLF *r_info);
+void blf_font_draw_buffer__wrap(struct FontBLF *font, const char *str, size_t len, struct ResultBLF *r_info);
 size_t blf_font_width_to_strlen(struct FontBLF *font, const char *str, size_t len, float width, float *r_width);
 size_t blf_font_width_to_rstrlen(struct FontBLF *font, const char *str, size_t len, float width, float *r_width);
-void blf_font_boundbox(struct FontBLF *font, const char *str, size_t len, struct rctf *box);
-void blf_font_width_and_height(struct FontBLF *font, const char *str, size_t len, float *width, float *height);
-float blf_font_width(struct FontBLF *font, const char *str, size_t len);
-float blf_font_height(struct FontBLF *font, const char *str, size_t len);
+void blf_font_boundbox(struct FontBLF *font, const char *str, size_t len, struct rctf *r_box, struct ResultBLF *r_info);
+void blf_font_boundbox__wrap(struct FontBLF *font, const char *str, size_t len, struct rctf *r_box, struct ResultBLF *r_info);
+void blf_font_width_and_height(struct FontBLF *font, const char *str, size_t len, float *r_width, float *r_height, struct ResultBLF *r_info);
+float blf_font_width(struct FontBLF *font, const char *str, size_t len, struct ResultBLF *r_info);
+float blf_font_height(struct FontBLF *font, const char *str, size_t len, struct ResultBLF *r_info);
 float blf_font_fixed_width(struct FontBLF *font);
 
 int blf_font_count_missing_chars(struct FontBLF *font, const char *str, const size_t len, int *r_tot_chars);