[TextServer / Font] Add support for customizable baseline offset.

2 files changed, 50 insertions, 2 deletions

diff --git a/modules/text_server_adv/text_server_adv.cpp b/modules/text_server_adv/text_server_adv.cpp
index 19f302423c..b4028492c7 100644
--- a/modules/text_server_adv/text_server_adv.cpp
+++ b/modules/text_server_adv/text_server_adv.cpp
@@ -2409,6 +2409,37 @@ int64_t TextServerAdvanced::_font_get_spacing(const RID &p_font_rid, SpacingType
 	}
 }
 
+void TextServerAdvanced::_font_set_baseline_offset(const RID &p_font_rid, float p_baseline_offset) {
+	FontAdvancedLinkedVariation *fdv = font_var_owner.get_or_null(p_font_rid);
+	if (fdv) {
+		if (fdv->baseline_offset != p_baseline_offset) {
+			fdv->baseline_offset = p_baseline_offset;
+		}
+	} else {
+		FontAdvanced *fd = font_owner.get_or_null(p_font_rid);
+		ERR_FAIL_NULL(fd);
+
+		MutexLock lock(fd->mutex);
+		if (fd->baseline_offset != p_baseline_offset) {
+			_font_clear_cache(fd);
+			fd->baseline_offset = p_baseline_offset;
+		}
+	}
+}
+
+float TextServerAdvanced::_font_get_baseline_offset(const RID &p_font_rid) const {
+	FontAdvancedLinkedVariation *fdv = font_var_owner.get_or_null(p_font_rid);
+	if (fdv) {
+		return fdv->baseline_offset;
+	} else {
+		FontAdvanced *fd = font_owner.get_or_null(p_font_rid);
+		ERR_FAIL_NULL_V(fd, 0.0);
+
+		MutexLock lock(fd->mutex);
+		return fd->baseline_offset;
+	}
+}
+
 void TextServerAdvanced::_font_set_transform(const RID &p_font_rid, const Transform2D &p_transform) {
 	FontAdvanced *fd = _get_font_data(p_font_rid);
 	ERR_FAIL_NULL(fd);
@@ -5750,6 +5781,11 @@ Glyph TextServerAdvanced::_shape_single_glyph(ShapedTextDataAdvanced *p_sd, char
 			gl.x_off = Math::round((double)glyph_pos[0].x_offset / (64.0 / scale));
 		}
 		gl.y_off = -Math::round((double)glyph_pos[0].y_offset / (64.0 / scale));
+		if (p_sd->orientation == ORIENTATION_HORIZONTAL) {
+			gl.y_off += _font_get_baseline_offset(gl.font_rid) * (double)(_font_get_ascent(gl.font_rid, gl.font_size) + _font_get_descent(gl.font_rid, gl.font_size));
+		} else {
+			gl.x_off += _font_get_baseline_offset(gl.font_rid) * (double)(_font_get_ascent(gl.font_rid, gl.font_size) + _font_get_descent(gl.font_rid, gl.font_size));
+		}
 
 		if ((glyph_info[0].codepoint != 0) || !u_isgraph(p_char)) {
 			gl.flags |= GRAPHEME_IS_VALID;
@@ -5964,6 +6000,11 @@ void TextServerAdvanced::_shape_run(ShapedTextDataAdvanced *p_sd, int64_t p_star
 					gl.x_off = Math::round((double)glyph_pos[i].x_offset / (64.0 / scale));
 				}
 				gl.y_off = -Math::round((double)glyph_pos[i].y_offset / (64.0 / scale));
+				if (p_sd->orientation == ORIENTATION_HORIZONTAL) {
+					gl.y_off += _font_get_baseline_offset(gl.font_rid) * (double)(_font_get_ascent(gl.font_rid, gl.font_size) + _font_get_descent(gl.font_rid, gl.font_size));
+				} else {
+					gl.x_off += _font_get_baseline_offset(gl.font_rid) * (double)(_font_get_ascent(gl.font_rid, gl.font_size) + _font_get_descent(gl.font_rid, gl.font_size));
+				}
 			}
 			if (!last_run || i < glyph_count - 1) {
 				// Do not add extra spacing to the last glyph of the string.
diff --git a/modules/text_server_adv/text_server_adv.h b/modules/text_server_adv/text_server_adv.h
index 0b5fe47b8b..6f53ecfa8f 100644
--- a/modules/text_server_adv/text_server_adv.h
+++ b/modules/text_server_adv/text_server_adv.h
@@ -297,6 +297,7 @@ class TextServerAdvanced : public TextServerExtension {
 	struct FontAdvancedLinkedVariation {
 		RID base_font;
 		int extra_spacing[4] = { 0, 0, 0, 0 };
+		float baseline_offset = 0.0;
 	};
 
 	struct FontAdvanced {
@@ -324,6 +325,7 @@ class TextServerAdvanced : public TextServerExtension {
 		int weight = 400;
 		int stretch = 100;
 		int extra_spacing[4] = { 0, 0, 0, 0 };
+		float baseline_offset = 0.0;
 
 		HashMap<Vector2i, FontForSizeAdvanced *, VariantHasher, VariantComparator> cache;
 
@@ -574,9 +576,10 @@ class TextServerAdvanced : public TextServerExtension {
 		double embolden = 0.0;
 		Transform2D transform;
 		int extra_spacing[4] = { 0, 0, 0, 0 };
+		float baseline_offset = 0.0;
 
 		bool operator==(const SystemFontKey &p_b) const {
-			return (font_name == p_b.font_name) && (antialiasing == p_b.antialiasing) && (italic == p_b.italic) && (mipmaps == p_b.mipmaps) && (msdf == p_b.msdf) && (force_autohinter == p_b.force_autohinter) && (weight == p_b.weight) && (stretch == p_b.stretch) && (msdf_range == p_b.msdf_range) && (msdf_source_size == p_b.msdf_source_size) && (fixed_size == p_b.fixed_size) && (hinting == p_b.hinting) && (subpixel_positioning == p_b.subpixel_positioning) && (variation_coordinates == p_b.variation_coordinates) && (oversampling == p_b.oversampling) && (embolden == p_b.embolden) && (transform == p_b.transform) && (extra_spacing[SPACING_TOP] == p_b.extra_spacing[SPACING_TOP]) && (extra_spacing[SPACING_BOTTOM] == p_b.extra_spacing[SPACING_BOTTOM]) && (extra_spacing[SPACING_SPACE] == p_b.extra_spacing[SPACING_SPACE]) && (extra_spacing[SPACING_GLYPH] == p_b.extra_spacing[SPACING_GLYPH]);
+			return (font_name == p_b.font_name) && (antialiasing == p_b.antialiasing) && (italic == p_b.italic) && (mipmaps == p_b.mipmaps) && (msdf == p_b.msdf) && (force_autohinter == p_b.force_autohinter) && (weight == p_b.weight) && (stretch == p_b.stretch) && (msdf_range == p_b.msdf_range) && (msdf_source_size == p_b.msdf_source_size) && (fixed_size == p_b.fixed_size) && (hinting == p_b.hinting) && (subpixel_positioning == p_b.subpixel_positioning) && (variation_coordinates == p_b.variation_coordinates) && (oversampling == p_b.oversampling) && (embolden == p_b.embolden) && (transform == p_b.transform) && (extra_spacing[SPACING_TOP] == p_b.extra_spacing[SPACING_TOP]) && (extra_spacing[SPACING_BOTTOM] == p_b.extra_spacing[SPACING_BOTTOM]) && (extra_spacing[SPACING_SPACE] == p_b.extra_spacing[SPACING_SPACE]) && (extra_spacing[SPACING_GLYPH] == p_b.extra_spacing[SPACING_GLYPH]) && (baseline_offset == p_b.baseline_offset);
 		}
 
 		SystemFontKey(const String &p_font_name, bool p_italic, int p_weight, int p_stretch, RID p_font, const TextServerAdvanced *p_fb) {
@@ -601,6 +604,7 @@ class TextServerAdvanced : public TextServerExtension {
 			extra_spacing[SPACING_BOTTOM] = p_fb->_font_get_spacing(p_font, SPACING_BOTTOM);
 			extra_spacing[SPACING_SPACE] = p_fb->_font_get_spacing(p_font, SPACING_SPACE);
 			extra_spacing[SPACING_GLYPH] = p_fb->_font_get_spacing(p_font, SPACING_GLYPH);
+			baseline_offset = p_fb->_font_get_baseline_offset(p_font);
 		}
 	};
 
@@ -633,7 +637,7 @@ class TextServerAdvanced : public TextServerExtension {
 			hash = hash_murmur3_one_32(p_a.extra_spacing[SPACING_BOTTOM], hash);
 			hash = hash_murmur3_one_32(p_a.extra_spacing[SPACING_SPACE], hash);
 			hash = hash_murmur3_one_32(p_a.extra_spacing[SPACING_GLYPH], hash);
-
+			hash = hash_murmur3_one_double(p_a.baseline_offset, hash);
 			return hash_fmix32(hash_murmur3_one_32(((int)p_a.mipmaps) | ((int)p_a.msdf << 1) | ((int)p_a.italic << 2) | ((int)p_a.force_autohinter << 3) | ((int)p_a.hinting << 4) | ((int)p_a.subpixel_positioning << 8) | ((int)p_a.antialiasing << 12), hash));
 		}
 	};
@@ -781,6 +785,9 @@ public:
 	MODBIND3(font_set_spacing, const RID &, SpacingType, int64_t);
 	MODBIND2RC(int64_t, font_get_spacing, const RID &, SpacingType);
 
+	MODBIND2(font_set_baseline_offset, const RID &, float);
+	MODBIND1RC(float, font_get_baseline_offset, const RID &);
+
 	MODBIND2(font_set_transform, const RID &, const Transform2D &);
 	MODBIND1RC(Transform2D, font_get_transform, const RID &);