Commit: b9c0eed206b0d7d1b6af6809c6d2cb6c2187bcc8 Author: Harley Acheson Date: Thu Jul 7 12:59:16 2022 -0700 Branches: master https://developer.blender.org/rBb9c0eed206b0d7d1b6af6809c6d2cb6c2187bcc8
BLF: Add Support for Variable Fonts Add support for Variable/Multiple Master font features. These are fonts that contain a range of design variations along multiple axes. This contains no client-facing options. See D12977 for details and examples Differential Revision: https://developer.blender.org/D12977 Reviewed by Brecht Van Lommel =================================================================== M source/blender/blenfont/intern/blf_font.c M source/blender/blenfont/intern/blf_glyph.c M source/blender/blenfont/intern/blf_internal_types.h =================================================================== diff --git a/source/blender/blenfont/intern/blf_font.c b/source/blender/blenfont/intern/blf_font.c index 3e2927d581e..038e73cc928 100644 --- a/source/blender/blenfont/intern/blf_font.c +++ b/source/blender/blenfont/intern/blf_font.c @@ -18,7 +18,8 @@ #include FT_FREETYPE_H #include FT_GLYPH_H -#include FT_TRUETYPE_TABLES_H /* For TT_OS2 */ +#include FT_TRUETYPE_TABLES_H /* For TT_OS2 */ +#include FT_MULTIPLE_MASTERS_H /* Variable font support. */ #include "MEM_guardedalloc.h" @@ -1285,6 +1286,10 @@ FontBLF *blf_font_new(const char *name, const char *filepath) MEM_freeN(mfile); } + if (FT_HAS_MULTIPLE_MASTERS(font->face)) { + FT_Get_MM_Var(font->face, &(font->variations)); + } + font->name = BLI_strdup(name); font->filepath = BLI_strdup(filepath); blf_font_fill(font); @@ -1351,6 +1356,10 @@ FontBLF *blf_font_new_from_mem(const char *name, const unsigned char *mem, int m return NULL; } + if (FT_HAS_MULTIPLE_MASTERS(font->face)) { + FT_Get_MM_Var(font->face, &(font->variations)); + } + font->name = BLI_strdup(name); font->filepath = NULL; blf_font_fill(font); @@ -1365,6 +1374,10 @@ void blf_font_free(FontBLF *font) MEM_freeN(font->kerning_cache); } + if (font->variations) { + FT_Done_MM_Var(ft_lib, font->variations); + } + FT_Done_Face(font->face); if (font->filepath) { MEM_freeN(font->filepath); diff --git a/source/blender/blenfont/intern/blf_glyph.c b/source/blender/blenfont/intern/blf_glyph.c index 2eb43e3df43..4db083366c3 100644 --- a/source/blender/blenfont/intern/blf_glyph.c +++ b/source/blender/blenfont/intern/blf_glyph.c @@ -18,7 +18,8 @@ #include FT_GLYPH_H #include FT_OUTLINE_H #include FT_BITMAP_H -#include FT_ADVANCES_H /* For FT_Get_Advance. */ +#include FT_ADVANCES_H /* For FT_Get_Advance. */ +#include FT_MULTIPLE_MASTERS_H /* Variable font support. */ #include "MEM_guardedalloc.h" @@ -64,7 +65,9 @@ static GlyphCacheBLF *blf_glyph_cache_find(FontBLF *font, float size, unsigned i GlyphCacheBLF *gc = (GlyphCacheBLF *)font->cache.first; while (gc) { if (gc->size == size && gc->dpi == dpi && (gc->bold == ((font->flags & BLF_BOLD) != 0)) && - (gc->italic == ((font->flags & BLF_ITALIC) != 0))) { + (gc->italic == ((font->flags & BLF_ITALIC) != 0)) && + (gc->char_weight == font->char_weight) && (gc->char_slant == font->char_slant) && + (gc->char_width == font->char_width) && (gc->char_spacing == font->char_spacing)) { return gc; } gc = gc->next; @@ -82,6 +85,10 @@ static GlyphCacheBLF *blf_glyph_cache_new(FontBLF *font) gc->dpi = font->dpi; gc->bold = ((font->flags & BLF_BOLD) != 0); gc->italic = ((font->flags & BLF_ITALIC) != 0); + gc->char_weight = font->char_weight; + gc->char_slant = font->char_slant; + gc->char_width = font->char_width; + gc->char_spacing = font->char_spacing; memset(gc->glyph_ascii_table, 0, sizeof(gc->glyph_ascii_table)); memset(gc->bucket, 0, sizeof(gc->bucket)); @@ -673,6 +680,96 @@ static bool blf_glyph_render_bitmap(FontBLF *font, FT_GlyphSlot glyph) /** \} */ +/* -------------------------------------------------------------------- */ +/** \name Variations (Multiple Masters) support + * \{ */ + +/** + * Return a design axis that matches an identifying tag. + * + * \param variations: Variation descriptors from `FT_Get_MM_Var`. + * \param tag: Axis tag (4-character string as uint), like 'wght' + * \param axis_index: returns index of axis in variations array. + */ +static FT_Var_Axis *blf_var_axis_by_tag(FT_MM_Var *variations, uint tag, int *axis_index) +{ + *axis_index = -1; + if (!variations) { + return NULL; + } + for (int i = 0; i < (int)variations->num_axis; i++) { + if (variations->axis[i].tag == tag) { + *axis_index = i; + return &(variations->axis)[i]; + break; + } + } + return NULL; +} + +/** + * Convert a float factor to a fixed-point design coordinate. + * + * \param axis: Pointer to a design space axis structure. + * \param factor: -1 to 1 with 0 meaning "default" + */ +static FT_Fixed blf_factor_to_coordinate(FT_Var_Axis *axis, float factor) +{ + FT_Fixed value = axis->def; + if (factor > 0) { + /* Map 0-1 to axis->def - axis->maximum */ + value += (FT_Fixed)((double)(axis->maximum - axis->def) * factor); + } + else if (factor < 0) { + /* Map -1-0 to axis->minimum - axis->def */ + value += (FT_Fixed)((double)(axis->def - axis->minimum) * factor); + } + return value; +} + +/** + * Alter a face variation axis by a factor + * + * \param coords: array of design coordinates, per axis. + * \param tag: Axis tag (4-character string as uint), like 'wght' + * \param factor: -1 to 1 with 0 meaning "default" + */ +static bool blf_glyph_set_variation_normalized(FontBLF *font, + FT_Fixed coords[], + uint tag, + float factor) +{ + int axis_index; + FT_Var_Axis *axis = blf_var_axis_by_tag(font->variations, tag, &axis_index); + if (axis && (axis_index < BLF_VARIATIONS_MAX)) { + coords[axis_index] = blf_factor_to_coordinate(axis, factor); + return true; + } + return false; +} + +/** + * Set a face variation axis to an exact float value + * + * \param coords: array of design coordinates, per axis. + * \param tag: Axis tag (4-character string as uint), like 'opsz' + * \param value: New float value. Converted to 16.16 and clamped within allowed range. + */ +static bool blf_glyph_set_variation_float(FontBLF *font, FT_Fixed coords[], uint tag, float value) +{ + int axis_index; + FT_Var_Axis *axis = blf_var_axis_by_tag(font->variations, tag, &axis_index); + if (axis && (axis_index < BLF_VARIATIONS_MAX)) { + FT_Fixed int_value = to_16dot16(value); + CLAMP(int_value, axis->minimum, axis->maximum); + coords[axis_index] = int_value; + return true; + } + return false; +} + +/** \} */ + /* -------------------------------------------------------------------- */ /** \name Glyph Transformations * \{ */ @@ -682,9 +779,7 @@ static bool blf_glyph_render_bitmap(FontBLF *font, FT_GlyphSlot glyph) * * \param factor: -1 (min stroke width) <= 0 (normal) => 1 (max boldness). */ -static bool UNUSED_FUNCTION(blf_glyph_transform_weight)(FT_GlyphSlot glyph, - float factor, - bool monospaced) +static bool blf_glyph_transform_weight(FT_GlyphSlot glyph, float factor, bool monospaced) { if (glyph->format == FT_GLYPH_FORMAT_OUTLINE) { /* Fake bold if the font does not have this variable axis. */ @@ -713,7 +808,7 @@ static bool UNUSED_FUNCTION(blf_glyph_transform_weight)(FT_GlyphSlot glyph, * * \note that left-leaning italics are possible in some RTL writing systems. */ -static bool UNUSED_FUNCTION(blf_glyph_transform_slant)(FT_GlyphSlot glyph, float factor) +static bool blf_glyph_transform_slant(FT_GlyphSlot glyph, float factor) { if (glyph->format == FT_GLYPH_FORMAT_OUTLINE) { FT_Matrix transform = {to_16dot16(1), to_16dot16(factor / 2.0f), 0, to_16dot16(1)}; @@ -728,7 +823,7 @@ static bool UNUSED_FUNCTION(blf_glyph_transform_slant)(FT_GlyphSlot glyph, float * * \param factor: -1 (min width) <= 0 (normal) => 1 (max width). */ -static bool UNUSED_FUNCTION(blf_glyph_transform_width)(FT_GlyphSlot glyph, float factor) +static bool blf_glyph_transform_width(FT_GlyphSlot glyph, float factor) { if (glyph->format == FT_GLYPH_FORMAT_OUTLINE) { float scale = (factor * 0.4f) + 1.0f; /* 0.6f - 1.4f */ @@ -740,6 +835,21 @@ static bool UNUSED_FUNCTION(blf_glyph_transform_width)(FT_GlyphSlot glyph, float return false; } +/** + * Change glyph advance to alter letter-spacing (tracking). + * + * \param factor: -1 (min tightness) <= 0 (normal) => 1 (max looseness). + */ +static bool blf_glyph_transform_spacing(FT_GlyphSlot glyph, float factor) +{ + if (glyph->advance.x > 0) { + const int size = glyph->face->size->metrics.height; + glyph->advance.x += (FT_Pos)(factor * (float)size / 6.0f); + return true; + } + return false; +} + /** * Transform glyph to fit nicely within a fixed column width. */ @@ -791,6 +901,48 @@ static FT_GlyphSlot blf_glyph_render(FontBLF *settings_font, glyph_font->dpi = settings_font->dpi; } + /* We need to keep track if changes are still needed. */ + bool weight_done = false; + bool slant_done = false; + bool width_done = false; + bool spacing_done = false; + + /* 70% of maximum weight results in the same amount of boldness and horizontal + * expansion as the bold version (DejaVuSans-Bold.ttf) of our default font. + * Worth reevaluating if we change default font. */ + float weight = (settings_font->flags & BLF_BOLD) ? 0.7f : settings_font->char_weight; + + /* 37.5% of maximum rightward slant results in 6 degree slope, matching italic + * version (DejaVuSans-Oblique.ttf) of our current font. But a nice median when + * checking others. Worth reevaluating if we change default font. We could also + * narrow the glyph slightly as most italics do, but this one does not. */ + float slant = (settings_font->flags & BLF_ITALIC) ? 0.375f : settings_font->char_slant; + + float width = settings_font->char_width; + float spacing = settings_font->char_spacing; + + /* Font variations need to be set before glyph loading. Even if new value is zero. */ + + if (glyph_font->variations) { + FT_Fixed coords[BLF_VARIATIONS_MAX]; + /* Load current design coordinates. */ + FT_Get_Var_Design_Coordinates(glyph_font->face, BLF_VARIATIONS_MAX, &coords[0]); + /* Update design coordinates with new values. */ + weight_done = blf_glyph_set_variation_normalized( + glyph_font, coords, blf_variation_axis_weight, weight); + slant_done = blf_glyph_set_variation_normalized( + glyph_font, coords, blf_variation_axis_slant, slant); + width_done = blf_glyph_set_variation_normalized( + glyph_font, coords, blf_variation_axis_width, width); + spacing_done = blf_glyph_set_variation_normalized( + glyph_font, coords, blf_variation_axis_spacing, sp @@ Diff output truncated at 10240 characters. @@ _______________________________________________ Bf-blender-cvs mailing list Bf-blender-cvs@blender.org List details, subscription details or unsubscribe: https://lists.blender.org/mailman/listinfo/bf-blender-cvs
