Fonts: added AddFontDefaultVector() with embedded ProggyVector data.

docs/CHANGELOG.txt

@@ -69,6 +69,13 @@ Breaking Changes:
 Other Changes:
 
 - Fonts:
+  - Added AddFontDefaultVector(): a new embedded scalable font!
+    Based on ProggyVector by Tristan Grimmer, the same author as our good-old ProggyClean.
+    The font data was carefully subsetted, trimmed and compressed so the embedded
+    data is ~18 KB. Embedding a scalable default font ensures that Dear ImGui can
+    be easily and readily used in all contexts, even without file system access.
+    As always you can opt-out of the embedded font data if desired. A sizing tweak
+    was also applied to ensure the new font is a closer match to the classic font.
   - Fixed an issue related to EllipsisChar handling, while changing
     font loader or font loader flags dynamically in Style->Fonts menus.
   - imgui_freetype: fixed overwriting ImFontConfig::PixelSnapH when hinting

imgui.h

@@ -3640,7 +3640,8 @@ struct ImFontAtlas
     IMGUI_API ImFontAtlas();
     IMGUI_API ~ImFontAtlas();
     IMGUI_API ImFont*           AddFont(const ImFontConfig* font_cfg);
-    IMGUI_API ImFont*           AddFontDefault(const ImFontConfig* font_cfg = NULL);
+    IMGUI_API ImFont*           AddFontDefault(const ImFontConfig* font_cfg = NULL);        // Embedded classic pixel-clean font. Recommended at Size 13px with no scaling.
+    IMGUI_API ImFont*           AddFontDefaultVector(const ImFontConfig* font_cfg = NULL);  // Embedded scalable font. Recommended at any higher size.
     IMGUI_API ImFont*           AddFontFromFileTTF(const char* filename, float size_pixels = 0.0f, const ImFontConfig* font_cfg = NULL, const ImWchar* glyph_ranges = NULL);
     IMGUI_API ImFont*           AddFontFromMemoryTTF(void* font_data, int font_data_size, float size_pixels = 0.0f, const ImFontConfig* font_cfg = NULL, const ImWchar* glyph_ranges = NULL); // Note: Transfer ownership of 'ttf_data' to ImFontAtlas! Will be deleted after destruction of the atlas. Set font_cfg->FontDataOwnedByAtlas=false to keep ownership of your data and it won't be freed.
     IMGUI_API ImFont*           AddFontFromMemoryCompressedTTF(const void* compressed_font_data, int compressed_font_data_size, float size_pixels = 0.0f, const ImFontConfig* font_cfg = NULL, const ImWchar* glyph_ranges = NULL); // 'compressed_font_data' still owned by caller. Compress with binary_to_compressed_c.cpp.

misc/fonts/ProggyVector-ExtractScript.txt

@@ -0,0 +1,17 @@
+# Usage: fontforge.exe -script ProggyVector-ExtractScript.txt
+Open("ProggyVector-Regular.ttf")
+SelectMore(0x20,0xFF)
+SelectMore(0x20AC) # Euro sign
+SelectInvert()
+DetachAndRemoveGlyphs()
+SelectAll()
+RemoveOverlap()
+Simplify()
+i=0
+while (i < 23)
+	SetTTFName(0x409,i,"")
+	i=i+1
+endloop
+SetFontNames(".",".",".",".",".",".")
+Generate("ProggyVector-minimal.ttf")
+# At this point you can use binary_to_compressed_c.exe -u8 ProggyVector-minimal.ttf proggy_vector_minimal_ttf