[TextServer] Improve empty glyph handling to allow glyphs smaller than 2px and avoid unnecessary texture updates.

2 files changed, 54 insertions, 44 deletions

diff --git a/modules/text_server_adv/text_server_adv.cpp b/modules/text_server_adv/text_server_adv.cpp
index c092fd7511..1ed335fe99 100644
--- a/modules/text_server_adv/text_server_adv.cpp
+++ b/modules/text_server_adv/text_server_adv.cpp
@@ -958,7 +958,7 @@ void TextServerAdvanced::_generateMTSDF_threaded(void *p_td, uint32_t p_y) {
 	}
 }
 
-_FORCE_INLINE_ TextServerAdvanced::FontGlyph TextServerAdvanced::rasterize_msdf(FontAdvanced *p_font_data, FontForSizeAdvanced *p_data, int p_pixel_range, int p_rect_margin, FT_Outline *outline, const Vector2 &advance) const {
+_FORCE_INLINE_ TextServerAdvanced::FontGlyph TextServerAdvanced::rasterize_msdf(FontAdvanced *p_font_data, FontForSizeAdvanced *p_data, int p_pixel_range, int p_rect_margin, FT_Outline *p_outline, const Vector2 &p_advance) const {
 	msdfgen::Shape shape;
 
 	shape.contours.clear();
@@ -974,13 +974,13 @@ _FORCE_INLINE_ TextServerAdvanced::FontGlyph TextServerAdvanced::rasterize_msdf(
 	ft_functions.shift = 0;
 	ft_functions.delta = 0;
 
-	int error = FT_Outline_Decompose(outline, &ft_functions, &context);
+	int error = FT_Outline_Decompose(p_outline, &ft_functions, &context);
 	ERR_FAIL_COND_V_MSG(error, FontGlyph(), "FreeType: Outline decomposition error: '" + String(FT_Error_String(error)) + "'.");
 	if (!shape.contours.empty() && shape.contours.back().edges.empty()) {
 		shape.contours.pop_back();
 	}
 
-	if (FT_Outline_Get_Orientation(outline) == 1) {
+	if (FT_Outline_Get_Orientation(p_outline) == 1) {
 		for (int i = 0; i < (int)shape.contours.size(); ++i) {
 			shape.contours[i].reverse();
 		}
@@ -993,12 +993,19 @@ _FORCE_INLINE_ TextServerAdvanced::FontGlyph TextServerAdvanced::rasterize_msdf(
 
 	FontGlyph chr;
 	chr.found = true;
-	chr.advance = advance;
+	chr.advance = p_advance;
 
 	if (shape.validate() && shape.contours.size() > 0) {
 		int w = (bounds.r - bounds.l);
 		int h = (bounds.t - bounds.b);
 
+		if (w == 0 || h == 0) {
+			chr.texture_idx = -1;
+			chr.uv_rect = Rect2();
+			chr.rect = Rect2();
+			return chr;
+		}
+
 		int mw = w + p_rect_margin * 4;
 		int mh = h + p_rect_margin * 4;
 
@@ -1056,12 +1063,24 @@ _FORCE_INLINE_ TextServerAdvanced::FontGlyph TextServerAdvanced::rasterize_msdf(
 #endif
 
 #ifdef MODULE_FREETYPE_ENABLED
-_FORCE_INLINE_ TextServerAdvanced::FontGlyph TextServerAdvanced::rasterize_bitmap(FontForSizeAdvanced *p_data, int p_rect_margin, FT_Bitmap bitmap, int yofs, int xofs, const Vector2 &advance, bool p_bgra) const {
-	int w = bitmap.width;
-	int h = bitmap.rows;
+_FORCE_INLINE_ TextServerAdvanced::FontGlyph TextServerAdvanced::rasterize_bitmap(FontForSizeAdvanced *p_data, int p_rect_margin, FT_Bitmap p_bitmap, int p_yofs, int p_xofs, const Vector2 &p_advance, bool p_bgra) const {
+	FontGlyph chr;
+	chr.advance = p_advance * p_data->scale / p_data->oversampling;
+	chr.found = true;
+
+	int w = p_bitmap.width;
+	int h = p_bitmap.rows;
+
+	if (w == 0 || h == 0) {
+		chr.texture_idx = -1;
+		chr.uv_rect = Rect2();
+		chr.rect = Rect2();
+		return chr;
+	}
+
 	int color_size = 2;
 
-	switch (bitmap.pixel_mode) {
+	switch (p_bitmap.pixel_mode) {
 		case FT_PIXEL_MODE_MONO:
 		case FT_PIXEL_MODE_GRAY: {
 			color_size = 2;
@@ -1100,54 +1119,54 @@ _FORCE_INLINE_ TextServerAdvanced::FontGlyph TextServerAdvanced::rasterize_bitma
 			for (int j = 0; j < w; j++) {
 				int ofs = ((i + tex_pos.y + p_rect_margin * 2) * tex.texture_w + j + tex_pos.x + p_rect_margin * 2) * color_size;
 				ERR_FAIL_COND_V(ofs >= tex.image->data_size(), FontGlyph());
-				switch (bitmap.pixel_mode) {
+				switch (p_bitmap.pixel_mode) {
 					case FT_PIXEL_MODE_MONO: {
-						int byte = i * bitmap.pitch + (j >> 3);
+						int byte = i * p_bitmap.pitch + (j >> 3);
 						int bit = 1 << (7 - (j % 8));
 						wr[ofs + 0] = 255; // grayscale as 1
-						wr[ofs + 1] = (bitmap.buffer[byte] & bit) ? 255 : 0;
+						wr[ofs + 1] = (p_bitmap.buffer[byte] & bit) ? 255 : 0;
 					} break;
 					case FT_PIXEL_MODE_GRAY:
 						wr[ofs + 0] = 255; // grayscale as 1
-						wr[ofs + 1] = bitmap.buffer[i * bitmap.pitch + j];
+						wr[ofs + 1] = p_bitmap.buffer[i * p_bitmap.pitch + j];
 						break;
 					case FT_PIXEL_MODE_BGRA: {
-						int ofs_color = i * bitmap.pitch + (j << 2);
-						wr[ofs + 2] = bitmap.buffer[ofs_color + 0];
-						wr[ofs + 1] = bitmap.buffer[ofs_color + 1];
-						wr[ofs + 0] = bitmap.buffer[ofs_color + 2];
-						wr[ofs + 3] = bitmap.buffer[ofs_color + 3];
+						int ofs_color = i * p_bitmap.pitch + (j << 2);
+						wr[ofs + 2] = p_bitmap.buffer[ofs_color + 0];
+						wr[ofs + 1] = p_bitmap.buffer[ofs_color + 1];
+						wr[ofs + 0] = p_bitmap.buffer[ofs_color + 2];
+						wr[ofs + 3] = p_bitmap.buffer[ofs_color + 3];
 					} break;
 					case FT_PIXEL_MODE_LCD: {
-						int ofs_color = i * bitmap.pitch + (j * 3);
+						int ofs_color = i * p_bitmap.pitch + (j * 3);
 						if (p_bgra) {
-							wr[ofs + 0] = bitmap.buffer[ofs_color + 2];
-							wr[ofs + 1] = bitmap.buffer[ofs_color + 1];
-							wr[ofs + 2] = bitmap.buffer[ofs_color + 0];
+							wr[ofs + 0] = p_bitmap.buffer[ofs_color + 2];
+							wr[ofs + 1] = p_bitmap.buffer[ofs_color + 1];
+							wr[ofs + 2] = p_bitmap.buffer[ofs_color + 0];
 							wr[ofs + 3] = 255;
 						} else {
-							wr[ofs + 0] = bitmap.buffer[ofs_color + 0];
-							wr[ofs + 1] = bitmap.buffer[ofs_color + 1];
-							wr[ofs + 2] = bitmap.buffer[ofs_color + 2];
+							wr[ofs + 0] = p_bitmap.buffer[ofs_color + 0];
+							wr[ofs + 1] = p_bitmap.buffer[ofs_color + 1];
+							wr[ofs + 2] = p_bitmap.buffer[ofs_color + 2];
 							wr[ofs + 3] = 255;
 						}
 					} break;
 					case FT_PIXEL_MODE_LCD_V: {
-						int ofs_color = i * bitmap.pitch * 3 + j;
+						int ofs_color = i * p_bitmap.pitch * 3 + j;
 						if (p_bgra) {
-							wr[ofs + 0] = bitmap.buffer[ofs_color + bitmap.pitch * 2];
-							wr[ofs + 1] = bitmap.buffer[ofs_color + bitmap.pitch];
-							wr[ofs + 2] = bitmap.buffer[ofs_color + 0];
+							wr[ofs + 0] = p_bitmap.buffer[ofs_color + p_bitmap.pitch * 2];
+							wr[ofs + 1] = p_bitmap.buffer[ofs_color + p_bitmap.pitch];
+							wr[ofs + 2] = p_bitmap.buffer[ofs_color + 0];
 							wr[ofs + 3] = 255;
 						} else {
-							wr[ofs + 0] = bitmap.buffer[ofs_color + 0];
-							wr[ofs + 1] = bitmap.buffer[ofs_color + bitmap.pitch];
-							wr[ofs + 2] = bitmap.buffer[ofs_color + bitmap.pitch * 2];
+							wr[ofs + 0] = p_bitmap.buffer[ofs_color + 0];
+							wr[ofs + 1] = p_bitmap.buffer[ofs_color + p_bitmap.pitch];
+							wr[ofs + 2] = p_bitmap.buffer[ofs_color + p_bitmap.pitch * 2];
 							wr[ofs + 3] = 255;
 						}
 					} break;
 					default:
-						ERR_FAIL_V_MSG(FontGlyph(), "Font uses unsupported pixel format: " + String::num_int64(bitmap.pixel_mode) + ".");
+						ERR_FAIL_V_MSG(FontGlyph(), "Font uses unsupported pixel format: " + String::num_int64(p_bitmap.pixel_mode) + ".");
 						break;
 				}
 			}
@@ -1156,13 +1175,10 @@ _FORCE_INLINE_ TextServerAdvanced::FontGlyph TextServerAdvanced::rasterize_bitma
 
 	tex.dirty = true;
 
-	FontGlyph chr;
-	chr.advance = advance * p_data->scale / p_data->oversampling;
 	chr.texture_idx = tex_pos.index;
-	chr.found = true;
 
 	chr.uv_rect = Rect2(tex_pos.x + p_rect_margin, tex_pos.y + p_rect_margin, w + p_rect_margin * 2, h + p_rect_margin * 2);
-	chr.rect.position = Vector2(xofs - p_rect_margin, -yofs - p_rect_margin) * p_data->scale / p_data->oversampling;
+	chr.rect.position = Vector2(p_xofs - p_rect_margin, -p_yofs - p_rect_margin) * p_data->scale / p_data->oversampling;
 	chr.rect.size = chr.uv_rect.size * p_data->scale / p_data->oversampling;
 	return chr;
 }
@@ -3619,9 +3635,6 @@ void TextServerAdvanced::_font_draw_glyph(const RID &p_font_rid, const RID &p_ca
 
 	const FontGlyph &gl = fd->cache[size]->glyph_map[index];
 	if (gl.found) {
-		if (gl.uv_rect.size.x <= 2 || gl.uv_rect.size.y <= 2) {
-			return; // Nothing to draw.
-		}
 		ERR_FAIL_COND(gl.texture_idx < -1 || gl.texture_idx >= fd->cache[size]->textures.size());
 
 		if (gl.texture_idx != -1) {
@@ -3730,9 +3743,6 @@ void TextServerAdvanced::_font_draw_glyph_outline(const RID &p_font_rid, const R
 
 	const FontGlyph &gl = fd->cache[size]->glyph_map[index];
 	if (gl.found) {
-		if (gl.uv_rect.size.x <= 2 || gl.uv_rect.size.y <= 2) {
-			return; // Nothing to draw.
-		}
 		ERR_FAIL_COND(gl.texture_idx < -1 || gl.texture_idx >= fd->cache[size]->textures.size());
 
 		if (gl.texture_idx != -1) {
diff --git a/modules/text_server_adv/text_server_adv.h b/modules/text_server_adv/text_server_adv.h
index 160eb27528..1cd73a6999 100644
--- a/modules/text_server_adv/text_server_adv.h
+++ b/modules/text_server_adv/text_server_adv.h
@@ -354,10 +354,10 @@ class TextServerAdvanced : public TextServerExtension {
 
 	_FORCE_INLINE_ FontTexturePosition find_texture_pos_for_glyph(FontForSizeAdvanced *p_data, int p_color_size, Image::Format p_image_format, int p_width, int p_height, bool p_msdf) const;
 #ifdef MODULE_MSDFGEN_ENABLED
-	_FORCE_INLINE_ FontGlyph rasterize_msdf(FontAdvanced *p_font_data, FontForSizeAdvanced *p_data, int p_pixel_range, int p_rect_margin, FT_Outline *outline, const Vector2 &advance) const;
+	_FORCE_INLINE_ FontGlyph rasterize_msdf(FontAdvanced *p_font_data, FontForSizeAdvanced *p_data, int p_pixel_range, int p_rect_margin, FT_Outline *p_outline, const Vector2 &p_advance) const;
 #endif
 #ifdef MODULE_FREETYPE_ENABLED
-	_FORCE_INLINE_ FontGlyph rasterize_bitmap(FontForSizeAdvanced *p_data, int p_rect_margin, FT_Bitmap bitmap, int yofs, int xofs, const Vector2 &advance, bool p_bgra) const;
+	_FORCE_INLINE_ FontGlyph rasterize_bitmap(FontForSizeAdvanced *p_data, int p_rect_margin, FT_Bitmap p_bitmap, int p_yofs, int p_xofs, const Vector2 &p_advance, bool p_bgra) const;
 #endif
 	_FORCE_INLINE_ bool _ensure_glyph(FontAdvanced *p_font_data, const Vector2i &p_size, int32_t p_glyph) const;
 	_FORCE_INLINE_ bool _ensure_cache_for_size(FontAdvanced *p_font_data, const Vector2i &p_size) const;