Fonts: assert when using MergeMode with an explicit size over a target font with an implicit size, as scale factor are likely erroneous. (#9361)

This commit is contained in:
ocornut
2026-04-13 16:45:18 +02:00
parent bbd0af7256
commit 3cd8683061
4 changed files with 17 additions and 2 deletions

View File

@@ -76,6 +76,8 @@ Other Changes:
before layout has been locked (first row or headers row submitted). (#8250)
- Fonts:
- imgui_freetype: add FreeType headers & compiled version in 'About Dear ImGui' details.
- Assert when using MergeMode with an explicit size over a target font with an implicit
size, as scale factor are likely erroneous. (#9361)
- Clipper:
- Improved error reporting when misusing the clipper inside a table (prioritize
reporting the common clipper error over a table sanity check assert). (#9350)

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@@ -3861,6 +3861,7 @@ enum ImFontFlags_
ImFontFlags_NoLoadError = 1 << 1, // Disable throwing an error/assert when calling AddFontXXX() with missing file/data. Calling code is expected to check AddFontXXX() return value.
ImFontFlags_NoLoadGlyphs = 1 << 2, // [Internal] Disable loading new glyphs.
ImFontFlags_LockBakedSizes = 1 << 3, // [Internal] Disable loading new baked sizes, disable garbage collecting current ones. e.g. if you want to lock a font to a single size. Important: if you use this to preload given sizes, consider the possibility of multiple font density used on Retina display.
ImFontFlags_ImplicitRefSize = 1 << 4, // [Internal] Reference size was not set explicitly.
};
// Font runtime data and rendering

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@@ -3039,7 +3039,7 @@ ImFont* ImFontAtlas::AddFont(const ImFontConfig* font_cfg_in)
}
else
{
IM_ASSERT(Fonts.Size > 0 && "Cannot use MergeMode for the first font"); // When using MergeMode make sure that a font has already been added before.
IM_ASSERT(Fonts.Size > 0 && "Cannot use MergeMode for the first font!"); // When using MergeMode make sure that a font has already been added before.
font = font_cfg_in->DstFont ? font_cfg_in->DstFont : Fonts.back();
ImFontAtlasFontDiscardBakes(this, font, 0); // Need to discard bakes if the font was already used, because baked->FontLoaderDatas[] will change size. (#9162)
}
@@ -3067,6 +3067,11 @@ ImFont* ImFontAtlas::AddFont(const ImFontConfig* font_cfg_in)
IM_ASSERT(font_cfg->FontLoader->FontBakedLoadGlyph != NULL);
IM_ASSERT(font_cfg->FontLoader->LoaderInit == NULL && font_cfg->FontLoader->LoaderShutdown == NULL); // FIXME-NEWATLAS: Unsupported yet.
}
// | Target w/ Implicit RefSize | Target w/ Explicit RefSize |
// Adding w/ Implicit RefSize: | OK (same scale) | OK (same scale) |
// Adding w/ Explicit RefSize: | KO | OK (custom scale) |
if (font_cfg_in->MergeMode && font_cfg_in->SizePixels > 0)
IM_ASSERT((font->Flags & ImFontFlags_ImplicitRefSize) == 0 && "Cannot use MergeMode with an explicit reference size when the destination font used an implicit reference size!");
IM_ASSERT(font_cfg->FontLoaderData == NULL);
if (!ImFontAtlasFontSourceInit(this, font_cfg))
@@ -3134,7 +3139,10 @@ ImFont* ImFontAtlas::AddFontDefaultBitmap(const ImFontConfig* font_cfg_template)
if (!font_cfg_template)
font_cfg.PixelSnapH = true; // Prevents sub-integer scaling factors at lower-level layers.
if (font_cfg.SizePixels <= 0.0f)
{
font_cfg.SizePixels = 13.0f; // This only serves (1) as a reference for GlyphOffset.y setting and (2) as a default for pre-1.92 backend.
font_cfg.Flags |= ImFontFlags_ImplicitRefSize;
}
if (font_cfg.Name[0] == '\0')
ImFormatString(font_cfg.Name, IM_COUNTOF(font_cfg.Name), "ProggyClean.ttf");
font_cfg.EllipsisChar = (ImWchar)0x0085;
@@ -3159,7 +3167,10 @@ ImFont* ImFontAtlas::AddFontDefaultVector(const ImFontConfig* font_cfg_template)
if (!font_cfg_template)
font_cfg.PixelSnapH = true; // Precisely match ProggyClean, but prevents sub-integer scaling factors at lower-level layers.
if (font_cfg.SizePixels <= 0.0f)
{
font_cfg.SizePixels = 13.0f;
font_cfg.Flags |= ImFontFlags_ImplicitRefSize;
}
if (font_cfg.Name[0] == '\0')
ImFormatString(font_cfg.Name, IM_COUNTOF(font_cfg.Name), "ProggyForever.ttf");
font_cfg.ExtraSizeScale *= 1.015f; // Match ProggyClean

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@@ -428,8 +428,9 @@ static bool ImGui_ImplFreeType_FontBakedInit(ImFontAtlas* atlas, ImFontConfig* s
{
IM_UNUSED(atlas);
float size = baked->Size;
const float ref_size = baked->OwnerFont->Sources[0]->SizePixels;
if (src->MergeMode && src->SizePixels != 0.0f)
size *= (src->SizePixels / baked->OwnerFont->Sources[0]->SizePixels);
size *= (src->SizePixels / ref_size);
size *= src->ExtraSizeScale;
ImGui_ImplFreeType_FontSrcData* bd_font_data = (ImGui_ImplFreeType_FontSrcData*)src->FontLoaderData;