Merge pull request #67409 from bruvzg/fix_oversampling_rounding

[TextServer] Do not round glyph advances / coordinates if font oversampling or bitmap glyph scaling is used.

2 files changed, 47 insertions, 36 deletions

diff --git a/modules/text_server_adv/text_server_adv.cpp b/modules/text_server_adv/text_server_adv.cpp
index a8f5a3802c..c0fec4531d 100644
--- a/modules/text_server_adv/text_server_adv.cpp
+++ b/modules/text_server_adv/text_server_adv.cpp
@@ -2630,9 +2630,10 @@ Vector2 TextServerAdvanced::_font_get_glyph_advance(const RID &p_font_rid, int64
 		ea.x = fd->embolden * double(size.x) / 64.0;
 	}
 
+	double scale = _font_get_scale(p_font_rid, p_size);
 	if (fd->msdf) {
 		return (gl[p_glyph | mod].advance + ea) * (double)p_size / (double)fd->msdf_source_size;
-	} else if ((fd->subpixel_positioning == SUBPIXEL_POSITIONING_DISABLED) || (fd->subpixel_positioning == SUBPIXEL_POSITIONING_AUTO && size.x > SUBPIXEL_POSITIONING_ONE_HALF_MAX_SIZE)) {
+	} else if ((scale == 1.0) && ((fd->subpixel_positioning == SUBPIXEL_POSITIONING_DISABLED) || (fd->subpixel_positioning == SUBPIXEL_POSITIONING_AUTO && size.x > SUBPIXEL_POSITIONING_ONE_HALF_MAX_SIZE))) {
 		return (gl[p_glyph | mod].advance + ea).round();
 	} else {
 		return gl[p_glyph | mod].advance + ea;
@@ -3261,13 +3262,15 @@ void TextServerAdvanced::_font_draw_glyph(const RID &p_font_rid, const RID &p_ca
 					Size2 csize = gl.rect.size * (double)p_size / (double)fd->msdf_source_size;
 					RenderingServer::get_singleton()->canvas_item_add_msdf_texture_rect_region(p_canvas, Rect2(cpos, csize), texture, gl.uv_rect, modulate, 0, fd->msdf_range);
 				} else {
+					double scale = _font_get_scale(p_font_rid, p_size);
 					Point2 cpos = p_pos;
-					cpos.y = Math::floor(cpos.y);
 					if ((fd->subpixel_positioning == SUBPIXEL_POSITIONING_ONE_QUARTER) || (fd->subpixel_positioning == SUBPIXEL_POSITIONING_AUTO && size.x <= SUBPIXEL_POSITIONING_ONE_QUARTER_MAX_SIZE)) {
-						cpos.x = ((int)Math::floor(cpos.x + 0.125));
+						cpos.x = cpos.x + 0.125;
 					} else if ((fd->subpixel_positioning == SUBPIXEL_POSITIONING_ONE_HALF) || (fd->subpixel_positioning == SUBPIXEL_POSITIONING_AUTO && size.x <= SUBPIXEL_POSITIONING_ONE_HALF_MAX_SIZE)) {
-						cpos.x = ((int)Math::floor(cpos.x + 0.25));
-					} else {
+						cpos.x = cpos.x + 0.25;
+					}
+					if (scale == 1.0) {
+						cpos.y = Math::floor(cpos.y);
 						cpos.x = Math::floor(cpos.x);
 					}
 					cpos += gl.rect.position;
@@ -3352,12 +3355,14 @@ void TextServerAdvanced::_font_draw_glyph_outline(const RID &p_font_rid, const R
 					RenderingServer::get_singleton()->canvas_item_add_msdf_texture_rect_region(p_canvas, Rect2(cpos, csize), texture, gl.uv_rect, modulate, p_outline_size * 2, fd->msdf_range);
 				} else {
 					Point2 cpos = p_pos;
-					cpos.y = Math::floor(cpos.y);
+					double scale = _font_get_scale(p_font_rid, p_size);
 					if ((fd->subpixel_positioning == SUBPIXEL_POSITIONING_ONE_QUARTER) || (fd->subpixel_positioning == SUBPIXEL_POSITIONING_AUTO && size.x <= SUBPIXEL_POSITIONING_ONE_QUARTER_MAX_SIZE)) {
-						cpos.x = ((int)Math::floor(cpos.x + 0.125));
+						cpos.x = cpos.x + 0.125;
 					} else if ((fd->subpixel_positioning == SUBPIXEL_POSITIONING_ONE_HALF) || (fd->subpixel_positioning == SUBPIXEL_POSITIONING_AUTO && size.x <= SUBPIXEL_POSITIONING_ONE_HALF_MAX_SIZE)) {
-						cpos.x = ((int)Math::floor(cpos.x + 0.25));
-					} else {
+						cpos.x = cpos.x + 0.25;
+					}
+					if (scale == 1.0) {
+						cpos.y = Math::floor(cpos.y);
 						cpos.x = Math::floor(cpos.x);
 					}
 					cpos += gl.rect.position;
@@ -4975,7 +4980,8 @@ bool TextServerAdvanced::_shaped_text_update_justification_ops(const RID &p_shap
 
 Glyph TextServerAdvanced::_shape_single_glyph(ShapedTextDataAdvanced *p_sd, char32_t p_char, hb_script_t p_script, hb_direction_t p_direction, const RID &p_font, int64_t p_font_size) {
 	hb_font_t *hb_font = _font_get_hb_handle(p_font, p_font_size);
-	bool subpos = (_font_get_subpixel_positioning(p_font) == SUBPIXEL_POSITIONING_ONE_HALF) || (_font_get_subpixel_positioning(p_font) == SUBPIXEL_POSITIONING_ONE_QUARTER) || (_font_get_subpixel_positioning(p_font) == SUBPIXEL_POSITIONING_AUTO && p_font_size <= SUBPIXEL_POSITIONING_ONE_HALF_MAX_SIZE);
+	double scale = _font_get_scale(p_font, p_font_size);
+	bool subpos = (scale != 1.0) || (_font_get_subpixel_positioning(p_font) == SUBPIXEL_POSITIONING_ONE_HALF) || (_font_get_subpixel_positioning(p_font) == SUBPIXEL_POSITIONING_ONE_QUARTER) || (_font_get_subpixel_positioning(p_font) == SUBPIXEL_POSITIONING_AUTO && p_font_size <= SUBPIXEL_POSITIONING_ONE_HALF_MAX_SIZE);
 	ERR_FAIL_COND_V(hb_font == nullptr, Glyph());
 
 	hb_buffer_clear_contents(p_sd->hb_buffer);
@@ -5001,25 +5007,24 @@ Glyph TextServerAdvanced::_shape_single_glyph(ShapedTextDataAdvanced *p_sd, char
 	gl.font_size = p_font_size;
 
 	if (glyph_count > 0) {
-		double scale = _font_get_scale(p_font, p_font_size);
 		if (p_sd->orientation == ORIENTATION_HORIZONTAL) {
 			if (subpos) {
-				gl.advance = glyph_pos[0].x_advance / (64.0 / scale) + _get_extra_advance(p_font, p_font_size);
+				gl.advance = (double)glyph_pos[0].x_advance / (64.0 / scale) + _get_extra_advance(p_font, p_font_size);
 			} else {
-				gl.advance = Math::round(glyph_pos[0].x_advance / (64.0 / scale) + _get_extra_advance(p_font, p_font_size));
+				gl.advance = Math::round((double)glyph_pos[0].x_advance / (64.0 / scale) + _get_extra_advance(p_font, p_font_size));
 			}
 		} else {
-			gl.advance = -Math::round(glyph_pos[0].y_advance / (64.0 / scale));
+			gl.advance = -Math::round((double)glyph_pos[0].y_advance / (64.0 / scale));
 		}
 		gl.count = 1;
 
 		gl.index = glyph_info[0].codepoint;
 		if (subpos) {
-			gl.x_off = glyph_pos[0].x_offset / (64.0 / scale);
+			gl.x_off = (double)glyph_pos[0].x_offset / (64.0 / scale);
 		} else {
-			gl.x_off = Math::round(glyph_pos[0].x_offset / (64.0 / scale));
+			gl.x_off = Math::round((double)glyph_pos[0].x_offset / (64.0 / scale));
 		}
-		gl.y_off = -Math::round(glyph_pos[0].y_offset / (64.0 / scale));
+		gl.y_off = -Math::round((double)glyph_pos[0].y_offset / (64.0 / scale));
 
 		if ((glyph_info[0].codepoint != 0) || !u_isgraph(p_char)) {
 			gl.flags |= GRAPHEME_IS_VALID;
@@ -5092,7 +5097,7 @@ void TextServerAdvanced::_shape_run(ShapedTextDataAdvanced *p_sd, int64_t p_star
 	double sp_gl = p_sd->extra_spacing[SPACING_GLYPH];
 	bool last_run = (p_sd->end == p_end);
 	double ea = _get_extra_advance(f, fs);
-	bool subpos = (_font_get_subpixel_positioning(f) == SUBPIXEL_POSITIONING_ONE_HALF) || (_font_get_subpixel_positioning(f) == SUBPIXEL_POSITIONING_ONE_QUARTER) || (_font_get_subpixel_positioning(f) == SUBPIXEL_POSITIONING_AUTO && fs <= SUBPIXEL_POSITIONING_ONE_HALF_MAX_SIZE);
+	bool subpos = (scale != 1.0) || (_font_get_subpixel_positioning(f) == SUBPIXEL_POSITIONING_ONE_HALF) || (_font_get_subpixel_positioning(f) == SUBPIXEL_POSITIONING_ONE_QUARTER) || (_font_get_subpixel_positioning(f) == SUBPIXEL_POSITIONING_AUTO && fs <= SUBPIXEL_POSITIONING_ONE_HALF_MAX_SIZE);
 	ERR_FAIL_COND(hb_font == nullptr);
 
 	hb_buffer_clear_contents(p_sd->hb_buffer);
@@ -5193,19 +5198,19 @@ void TextServerAdvanced::_shape_run(ShapedTextDataAdvanced *p_sd, int64_t p_star
 				_ensure_glyph(fd, fss, gl.index | mod);
 				if (p_sd->orientation == ORIENTATION_HORIZONTAL) {
 					if (subpos) {
-						gl.advance = glyph_pos[i].x_advance / (64.0 / scale) + ea;
+						gl.advance = (double)glyph_pos[i].x_advance / (64.0 / scale) + ea;
 					} else {
-						gl.advance = Math::round(glyph_pos[i].x_advance / (64.0 / scale) + ea);
+						gl.advance = Math::round((double)glyph_pos[i].x_advance / (64.0 / scale) + ea);
 					}
 				} else {
-					gl.advance = -Math::round(glyph_pos[i].y_advance / (64.0 / scale));
+					gl.advance = -Math::round((double)glyph_pos[i].y_advance / (64.0 / scale));
 				}
 				if (subpos) {
-					gl.x_off = glyph_pos[i].x_offset / (64.0 / scale);
+					gl.x_off = (double)glyph_pos[i].x_offset / (64.0 / scale);
 				} else {
-					gl.x_off = Math::round(glyph_pos[i].x_offset / (64.0 / scale));
+					gl.x_off = Math::round((double)glyph_pos[i].x_offset / (64.0 / scale));
 				}
-				gl.y_off = -Math::round(glyph_pos[i].y_offset / (64.0 / scale));
+				gl.y_off = -Math::round((double)glyph_pos[i].y_offset / (64.0 / scale));
 			}
 			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_fb/text_server_fb.cpp b/modules/text_server_fb/text_server_fb.cpp
index 24553dc9d9..cd8df34f60 100644
--- a/modules/text_server_fb/text_server_fb.cpp
+++ b/modules/text_server_fb/text_server_fb.cpp
@@ -1711,9 +1711,10 @@ Vector2 TextServerFallback::_font_get_glyph_advance(const RID &p_font_rid, int64
 		ea.x = fd->embolden * double(size.x) / 64.0;
 	}
 
+	double scale = _font_get_scale(p_font_rid, p_size);
 	if (fd->msdf) {
 		return (gl[p_glyph | mod].advance + ea) * (double)p_size / (double)fd->msdf_source_size;
-	} else if ((fd->subpixel_positioning == SUBPIXEL_POSITIONING_DISABLED) || (fd->subpixel_positioning == SUBPIXEL_POSITIONING_AUTO && size.x > SUBPIXEL_POSITIONING_ONE_HALF_MAX_SIZE)) {
+	} else if ((scale == 1.0) && ((fd->subpixel_positioning == SUBPIXEL_POSITIONING_DISABLED) || (fd->subpixel_positioning == SUBPIXEL_POSITIONING_AUTO && size.x > SUBPIXEL_POSITIONING_ONE_HALF_MAX_SIZE))) {
 		return (gl[p_glyph | mod].advance + ea).round();
 	} else {
 		return gl[p_glyph | mod].advance + ea;
@@ -2325,12 +2326,14 @@ void TextServerFallback::_font_draw_glyph(const RID &p_font_rid, const RID &p_ca
 					RenderingServer::get_singleton()->canvas_item_add_msdf_texture_rect_region(p_canvas, Rect2(cpos, csize), texture, gl.uv_rect, modulate, 0, fd->msdf_range);
 				} else {
 					Point2 cpos = p_pos;
-					cpos.y = Math::floor(cpos.y);
+					double scale = _font_get_scale(p_font_rid, p_size);
 					if ((fd->subpixel_positioning == SUBPIXEL_POSITIONING_ONE_QUARTER) || (fd->subpixel_positioning == SUBPIXEL_POSITIONING_AUTO && size.x <= SUBPIXEL_POSITIONING_ONE_QUARTER_MAX_SIZE)) {
-						cpos.x = ((int)Math::floor(cpos.x + 0.125));
+						cpos.x = cpos.x + 0.125;
 					} else if ((fd->subpixel_positioning == SUBPIXEL_POSITIONING_ONE_HALF) || (fd->subpixel_positioning == SUBPIXEL_POSITIONING_AUTO && size.x <= SUBPIXEL_POSITIONING_ONE_HALF_MAX_SIZE)) {
-						cpos.x = ((int)Math::floor(cpos.x + 0.25));
-					} else {
+						cpos.x = cpos.x + 0.25;
+					}
+					if (scale == 1.0) {
+						cpos.y = Math::floor(cpos.y);
 						cpos.x = Math::floor(cpos.x);
 					}
 					cpos += gl.rect.position;
@@ -2415,12 +2418,14 @@ void TextServerFallback::_font_draw_glyph_outline(const RID &p_font_rid, const R
 					RenderingServer::get_singleton()->canvas_item_add_msdf_texture_rect_region(p_canvas, Rect2(cpos, csize), texture, gl.uv_rect, modulate, p_outline_size * 2, fd->msdf_range);
 				} else {
 					Point2 cpos = p_pos;
-					cpos.y = Math::floor(cpos.y);
+					double scale = _font_get_scale(p_font_rid, p_size);
 					if ((fd->subpixel_positioning == SUBPIXEL_POSITIONING_ONE_QUARTER) || (fd->subpixel_positioning == SUBPIXEL_POSITIONING_AUTO && size.x <= SUBPIXEL_POSITIONING_ONE_QUARTER_MAX_SIZE)) {
-						cpos.x = ((int)Math::floor(cpos.x + 0.125));
+						cpos.x = cpos.x + 0.125;
 					} else if ((fd->subpixel_positioning == SUBPIXEL_POSITIONING_ONE_HALF) || (fd->subpixel_positioning == SUBPIXEL_POSITIONING_AUTO && size.x <= SUBPIXEL_POSITIONING_ONE_HALF_MAX_SIZE)) {
-						cpos.x = ((int)Math::floor(cpos.x + 0.25));
-					} else {
+						cpos.x = cpos.x + 0.25;
+					}
+					if (scale == 1.0) {
+						cpos.y = Math::floor(cpos.y);
 						cpos.x = Math::floor(cpos.x);
 					}
 					cpos += gl.rect.position;
@@ -3643,17 +3648,18 @@ bool TextServerFallback::_shaped_text_shape(const RID &p_shaped) {
 					}
 				}
 
+				double scale = _font_get_scale(gl.font_rid, gl.font_size);
 				if (gl.font_rid.is_valid()) {
-					bool subpos = (_font_get_subpixel_positioning(gl.font_rid) == SUBPIXEL_POSITIONING_ONE_HALF) || (_font_get_subpixel_positioning(gl.font_rid) == SUBPIXEL_POSITIONING_ONE_QUARTER) || (_font_get_subpixel_positioning(gl.font_rid) == SUBPIXEL_POSITIONING_AUTO && gl.font_size <= SUBPIXEL_POSITIONING_ONE_HALF_MAX_SIZE);
+					bool subpos = (scale != 1.0) || (_font_get_subpixel_positioning(gl.font_rid) == SUBPIXEL_POSITIONING_ONE_HALF) || (_font_get_subpixel_positioning(gl.font_rid) == SUBPIXEL_POSITIONING_ONE_QUARTER) || (_font_get_subpixel_positioning(gl.font_rid) == SUBPIXEL_POSITIONING_AUTO && gl.font_size <= SUBPIXEL_POSITIONING_ONE_HALF_MAX_SIZE);
 					if (sd->text[j - sd->start] != 0 && !is_linebreak(sd->text[j - sd->start])) {
 						if (sd->orientation == ORIENTATION_HORIZONTAL) {
-							gl.advance = Math::round(_font_get_glyph_advance(gl.font_rid, gl.font_size, gl.index).x);
+							gl.advance = _font_get_glyph_advance(gl.font_rid, gl.font_size, gl.index).x;
 							gl.x_off = 0;
 							gl.y_off = 0;
 							sd->ascent = MAX(sd->ascent, _font_get_ascent(gl.font_rid, gl.font_size));
 							sd->descent = MAX(sd->descent, _font_get_descent(gl.font_rid, gl.font_size));
 						} else {
-							gl.advance = Math::round(_font_get_glyph_advance(gl.font_rid, gl.font_size, gl.index).y);
+							gl.advance = _font_get_glyph_advance(gl.font_rid, gl.font_size, gl.index).y;
 							gl.x_off = -Math::round(_font_get_glyph_advance(gl.font_rid, gl.font_size, gl.index).x * 0.5);
 							gl.y_off = _font_get_ascent(gl.font_rid, gl.font_size);
 							sd->ascent = MAX(sd->ascent, Math::round(_font_get_glyph_advance(gl.font_rid, gl.font_size, gl.index).x * 0.5));