Proper UTF-16 and characters outside the BMP support

[SDLBugzilla]

This bug report was migrated from our old Bugzilla tracker.

Reported in version: unspecified
Reported for operating system, platform: Windows 10, x86_64

Comments on the original bug report:

On 2018-09-03 07:21:42 +0000, pjz wrote:

I propose a patch with added proper UTF-16 and characters outside the BMP support, which extends the fix to the bug # 3762. The code can be found at https://github.com/acmepjz/SDL_ttf/tree/utf16-fix.

• Change the UCS-2 code to UTF-16 code, which allows characters outside the BMP range

• Change various public functions (TTF_GlyphIsProvided, TTF_GlyphMetrics, TTF_RenderGlyph_***, etc.) to accept Uint32 for character instead of Uint16

• Also added a UTF-32 to UTF-8 conversion routine (which is only used in TTF_RenderGlyph_***)

[slouken]

Duplicate of #230