Fonts: Functions with a 'float size_pixels' parameter can accept zero if it is set in ImFontSize::SizePixels.

docs/CHANGELOG.txt

@@ -48,6 +48,7 @@ Other Changes:
 - Tables: Fix invalid data in TableGetSortSpecs() when SpecsDirty flag is unset. (#4233)
 - TabBar: Fixed using more than 32 KB-worth of tab names. (#4176)
 - Fixed printf-style format checks on non-MinGW flavors. (#4183, #3592)
+- Fonts: Functions with a 'float size_pixels' parameter can accept zero if it is set in ImFontSize::SizePixels.
 - Demo: Fixed requirement in 1.83 to link with imgui_demo.cpp if IMGUI_DISABLE_METRICS_WINDOW is not set. (#4171)
   Normally the right way to disable compiling the demo is to set IMGUI_DISABLE_DEMO_WINDOWS, but we want to avoid
   implying that the file is required.

imgui_draw.cpp

@@ -2167,7 +2167,7 @@ ImFont* ImFontAtlas::AddFontFromMemoryTTF(void* ttf_data, int ttf_size, float si
     IM_ASSERT(font_cfg.FontData == NULL);
     font_cfg.FontData = ttf_data;
     font_cfg.FontDataSize = ttf_size;
-    font_cfg.SizePixels = size_pixels;
+    font_cfg.SizePixels = size_pixels > 0.0f ? size_pixels : font_cfg.SizePixels;
     if (glyph_ranges)
         font_cfg.GlyphRanges = glyph_ranges;
     return AddFont(&font_cfg);

misc/freetype/imgui_freetype.cpp

@@ -648,6 +648,22 @@ bool ImFontAtlasBuildWithFreeTypeEx(FT_Library ft_library, ImFontAtlas* atlas, u
             const int tx = pack_rect.x + padding;
             const int ty = pack_rect.y + padding;
 
+            // Register glyph
+            float x0 = info.OffsetX + font_off_x;
+            float y0 = info.OffsetY + font_off_y;
+            float x1 = x0 + info.Width;
+            float y1 = y0 + info.Height;
+            float u0 = (tx) / (float)atlas->TexWidth;
+            float v0 = (ty) / (float)atlas->TexHeight;
+            float u1 = (tx + info.Width) / (float)atlas->TexWidth;
+            float v1 = (ty + info.Height) / (float)atlas->TexHeight;
+            dst_font->AddGlyph(&cfg, (ImWchar)src_glyph.Codepoint, x0, y0, x1, y1, u0, v0, u1, v1, info.AdvanceX);
+
+            ImFontGlyph* dst_glyph = &dst_font->Glyphs.back();
+            IM_ASSERT(dst_glyph->Codepoint == src_glyph.Codepoint);
+            if (src_glyph.Info.IsColored)
+                dst_glyph->Colored = tex_use_colors = true;
+
             // Blit from temporary buffer to final texture
             size_t blit_src_stride = (size_t)src_glyph.Info.Width;
             size_t blit_dst_stride = (size_t)atlas->TexWidth;
@@ -666,22 +682,6 @@ bool ImFontAtlasBuildWithFreeTypeEx(FT_Library ft_library, ImFontAtlas* atlas, u
                     for (int x = 0; x < info.Width; x++)
                         blit_dst[x] = blit_src[x];
             }
-
-            // Register glyph
-            float x0 = info.OffsetX + font_off_x;
-            float y0 = info.OffsetY + font_off_y;
-            float x1 = x0 + info.Width;
-            float y1 = y0 + info.Height;
-            float u0 = (tx) / (float)atlas->TexWidth;
-            float v0 = (ty) / (float)atlas->TexHeight;
-            float u1 = (tx + info.Width) / (float)atlas->TexWidth;
-            float v1 = (ty + info.Height) / (float)atlas->TexHeight;
-            dst_font->AddGlyph(&cfg, (ImWchar)src_glyph.Codepoint, x0, y0, x1, y1, u0, v0, u1, v1, info.AdvanceX);
-
-            ImFontGlyph* dst_glyph = &dst_font->Glyphs.back();
-            IM_ASSERT(dst_glyph->Codepoint == src_glyph.Codepoint);
-            if (src_glyph.Info.IsColored)
-                dst_glyph->Colored = tex_use_colors = true;
         }
 
         src_tmp.Rects = NULL;