TextRendering Extension fix mem leak + add new helpful metrics

Author: Erfan-Ahmadi

examples_tests

@@ -7,7 +7,6 @@
 
 #include "nabla.h"
 
-#include "nbl/video/utilities/CPropertyPool.h"
 #include <msdfgen/msdfgen.h>
 #include <ft2build.h>
 #include <nbl/builtin/hlsl/cpp_compat.hlsl>
@@ -43,6 +42,12 @@ class TextRenderer : public nbl::core::IReferenceCounted
 		auto error = FT_Init_FreeType(&m_ftLibrary);
 		assert(!error);
 	}
+
+	~TextRenderer()
+	{
+		auto error = FT_Done_FreeType(m_ftLibrary);
+		assert(!error);
+	}
 
 	// TODO: Remove these here, it's only used for customized tests such as building shapes for hatches
 	const FT_Library& getFreetypeLibrary() const { return m_ftLibrary; }
@@ -56,11 +61,23 @@ class TextRenderer : public nbl::core::IReferenceCounted
 class FontFace : public nbl::core::IReferenceCounted
 {
 public:
+
+	// Face Global Metrics/Settings
+	struct Metrics
+	{
+		// This value is the vertical distance between two consecutive baselines, expressed in font units. It is always positive.
+		float64_t height;
+		// The distance from the baseline to the highest or upper grid coordinate used to place an outline point. It is a positive value.
+		float64_t ascent;
+		// The distance from the baseline to the lowest grid coordinate used to place an outline point. this is almost always a negative value.
+		float64_t descent;
+	};
+
 	struct GlyphMetrics
 	{
 		// Offset that should be applied to the current baseline after this glyph is placed
 		float64_t2 advance;
-		// Offset that the image of the glyph should be placed from the current baseline start, horizontal refers to horizonral LTR or RTL Languages
+		// Offset of the glyph's top left from the current baseline start, horizontal refers to horizonral LTR or RTL Languages
 		float64_t2 horizontalBearing;
 		// Size of the glyph in the text line
 		float64_t2 size;
@@ -76,6 +93,12 @@ class FontFace : public nbl::core::IReferenceCounted
 		m_hash = std::hash<std::string>{}(path);
 	}
 
+	~FontFace()
+	{
+		auto error = FT_Done_Face(m_ftFace);
+		assert(!error);
+	}
+
 	static constexpr uint32_t InvalidGlyphIndex = ~0u;
 
 	uint32_t getGlyphIndex(wchar_t unicode)
@@ -88,7 +111,9 @@ class FontFace : public nbl::core::IReferenceCounted
 		return FT_Get_Char_Index(m_ftFace, unicode);
 	}
 
-	GlyphMetrics getGlyphMetricss(uint32_t glyphId);
+	Metrics getMetrics() const;
+
+	GlyphMetrics getGlyphMetrics(uint32_t glyphId);
 
 	// returns the cpu buffer for the generated MSDF texture with "TextRenderer::MSDFTextureFormat" format
 	// it will place the glyph in the center of msdfExtents considering the margin of msdfPixelRange

include/nbl/ext/TextRendering/TextRendering.h

@@ -1,4 +1,3 @@
-
 using namespace nbl;
 using namespace nbl::core;
 using namespace nbl::asset;
@@ -56,7 +55,16 @@ core::smart_refctd_ptr<ICPUBuffer> TextRenderer::generateShapeMSDF(msdfgen::Shap
 
 constexpr double FreeTypeFontScaling = 1.0 / 64.0;
 
-FontFace::GlyphMetrics FontFace::getGlyphMetricss(uint32_t glyphId)
+FontFace::Metrics FontFace::getMetrics() const
+{
+	Metrics ret = {};
+	ret.height = float64_t(m_ftFace->height) * FreeTypeFontScaling;
+	ret.ascent = float64_t(m_ftFace->ascender) * FreeTypeFontScaling;
+	ret.descent = float64_t(m_ftFace->descender) * FreeTypeFontScaling;
+	return ret;
+}
+
+FontFace::GlyphMetrics FontFace::getGlyphMetrics(uint32_t glyphId)
 {
 	auto slot = getGlyphSlot(glyphId);
 
@@ -164,4 +172,4 @@ msdfgen::Shape FontFace::generateGlyphShape(uint32_t glyphId)
 
 }
 }
-}
+}