From 8b3f07c7b5f146c63741b94a7536eec86825e7a4 Mon Sep 17 00:00:00 2001
From: Ryan Fleury <ryan.j.fleury@gmail.com>
Date: Sun, 11 May 2025 13:27:59 -0700
Subject: [PATCH] eliminate font fudge factors; fix size units in freetype
 backend; fix directory iteration lack-of-robustness-to-failed-dir-open

---
 src/font_provider/dwrite/font_provider_dwrite.c     | 3 +--
 src/font_provider/freetype/font_provider_freetype.c | 6 +++---
 src/os/core/linux/os_core_linux.c                   | 2 +-
 src/ui/ui_core.c                                    | 2 +-
 4 files changed, 6 insertions(+), 7 deletions(-)

diff --git a/src/font_provider/dwrite/font_provider_dwrite.c b/src/font_provider/dwrite/font_provider_dwrite.c
index ebf81ff4..2c2fa96e 100644
--- a/src/font_provider/dwrite/font_provider_dwrite.c
+++ b/src/font_provider/dwrite/font_provider_dwrite.c
@@ -525,14 +525,13 @@ fp_raster(Arena *arena, FP_Handle font_handle, F32 size, FP_RasterFlags flags, S
   }
   
   //- rjf: draw glyph run
-  Vec2F32 draw_p = {0, (F32)atlas_dim.y - 1};
+  Vec2F32 draw_p = {0, (F32)atlas_dim.y};
   if(font.face != 0)
   {
     F32 descent = round_f32((96.f/72.f)*size * font_metrics.descent / design_units_per_em);
     F32 line_gap = round_f32((96.f/72.f)*size * font_metrics.lineGap / design_units_per_em);
     draw_p.y -= descent;
     draw_p.y -= line_gap;
-    draw_p.y += 1;
   }
   DWRITE_GLYPH_RUN glyph_run = {0};
   if(font.face != 0)
diff --git a/src/font_provider/freetype/font_provider_freetype.c b/src/font_provider/freetype/font_provider_freetype.c
index 979d5133..b98735b8 100644
--- a/src/font_provider/freetype/font_provider_freetype.c
+++ b/src/font_provider/freetype/font_provider_freetype.c
@@ -68,11 +68,11 @@ fp_metrics_from_font(FP_Handle handle)
   FP_Metrics result = {0};
   if(font.face != 0)
   {
-    result.design_units_per_em = (F32)font.face->units_per_EM;
+    result.design_units_per_em = (F32)(font.face->units_per_EM * 72.f/96.f);
     result.ascent              = (F32)font.face->ascender;
     result.descent             = (F32)font.face->descender;
     result.line_gap            = (F32)(font.face->height - font.face->ascender + font.face->descender);
-    result.capital_height      = (F32)(font.face->ascender + font.face->descender);
+    result.capital_height      = (F32)(font.face->ascender);
   }
   return result;
 }
@@ -89,7 +89,7 @@ fp_raster(Arena *arena, FP_Handle handle, F32 size, FP_RasterFlags flags, String
     
     //- rjf: unpack font
     FT_Face face = font.face;
-    FT_Set_Pixel_Sizes(face, 0, (FT_UInt)size);
+    FT_Set_Pixel_Sizes(face, 0, (FT_UInt)((96.f/72.f) * size));
     S64 ascent  = face->size->metrics.ascender >> 6;
     S64 descent = abs_s64(face->size->metrics.descender >> 6);
     S64 height  = face->size->metrics.height >> 6;
diff --git a/src/os/core/linux/os_core_linux.c b/src/os/core/linux/os_core_linux.c
index 4555d5a9..a44072f7 100644
--- a/src/os/core/linux/os_core_linux.c
+++ b/src/os/core/linux/os_core_linux.c
@@ -569,7 +569,7 @@ os_file_iter_next(Arena *arena, OS_FileIter *iter, OS_FileInfo *info_out)
 {
   B32 good = 0;
   OS_LNX_FileIter *lnx_iter = (OS_LNX_FileIter *)iter->memory;
-  for(;;)
+  for(;lnx_iter->dir != 0;)
   {
     // rjf: get next entry
     lnx_iter->dp = readdir(lnx_iter->dir);
diff --git a/src/ui/ui_core.c b/src/ui/ui_core.c
index 37887e5d..0d3c78f3 100644
--- a/src/ui/ui_core.c
+++ b/src/ui/ui_core.c
@@ -2767,7 +2767,7 @@ ui_box_text_position(UI_Box *box)
   FNT_Tag font = box->font;
   F32 font_size = box->font_size;
   FNT_Metrics font_metrics = fnt_metrics_from_tag_size(font, font_size);
-  result.y = floor_f32((box->rect.p0.y + box->rect.p1.y)/2.f) + font_metrics.capital_height/2.f - 1.f;
+  result.y = floor_f32((box->rect.p0.y + box->rect.p1.y)/2.f) + font_metrics.ascent/2.f - 2.f;
   if(!fnt_tag_match(font, ui_icon_font()))
   {
     result.y += font_metrics.descent/2;