Make math renderer a singleton of itself

src/main/java/com/keenwrite/preview/MathRenderer.java


		/**
		+ * Singleton instance for rendering math symbols.
		+ */
		+ public static final MathRenderer MATH_RENDERER = new MathRenderer();
		+
		+ /**
		* Default font size in points.
		*/
		private static final float FONT_SIZE = 20f;

		private final TeXFont mTeXFont = createDefaultTeXFont( FONT_SIZE );
		private final TeXEnvironment mEnvironment = createTeXEnvironment( mTeXFont );
		private final SvgDomGraphics2D mGraphics = createSvgDomGraphics2D();

		- public MathRenderer() {
		+ private MathRenderer() {
		mGraphics.scale( FONT_SIZE, FONT_SIZE );
		}

src/main/java/com/keenwrite/preview/SvgReplacedElementFactory.java

		import static com.keenwrite.StatusBarNotifier.clue;
		import static com.keenwrite.io.MediaType.*;
		+import static com.keenwrite.preview.MathRenderer.MATH_RENDERER;
		import static com.keenwrite.preview.SvgRasterizer.BROKEN_IMAGE_PLACEHOLDER;
		import static com.keenwrite.preview.SvgRasterizer.rasterize;

		*/
		public class SvgReplacedElementFactory extends ReplacedElementAdapter {
		-
		- /**
		- * Implementation of the initialization-on-demand holder design pattern,
		- * an for a lazy-loaded singleton. In all versions of Java, the idiom enables
		- * a safe, highly concurrent lazy initialization of static fields with good
		- * performance. The implementation relies upon the initialization phase of
		- * execution within the Java Virtual Machine (JVM) as specified by the Java
		- * Language Specification.
		- */
		- private static class Container {
		- private static final MathRenderer INSTANCE = new MathRenderer();
		- }
		-
		- /**
		- * Returns the singleton instance for rendering math symbols.
		- *
		- * @return A non-null instance, loaded, configured, and ready to render math.
		- */
		- public static MathRenderer getInstance() {
		- return Container.INSTANCE;
		- }

		public static final String HTML_IMAGE = "img";

		case HTML_TEX ->
		// Convert the TeX element to a raster graphic.
		- raster = rasterize( getInstance().render( e.getTextContent() ) );
		+ raster = rasterize( MATH_RENDERER.render( e.getTextContent() ) );
		}

src/main/java/com/keenwrite/processors/markdown/tex/TexNodeRenderer.java

		import com.keenwrite.ExportFormat;
		import com.keenwrite.preview.SvgRasterizer;
		-import com.keenwrite.preview.SvgReplacedElementFactory;
		import com.vladsch.flexmark.html.HtmlWriter;
		import com.vladsch.flexmark.html.renderer.NodeRenderer;

		import java.util.Set;

		+import static com.keenwrite.preview.MathRenderer.MATH_RENDERER;
		import static com.keenwrite.processors.markdown.tex.TexNode.*;


		final NodeRendererContext context,
		final HtmlWriter html ) {
		- final var renderer = SvgReplacedElementFactory.getInstance();
		final var tex = node.getText().toStringOrNull();
		- final var doc = renderer.render( tex == null ? "" : tex );
		+ final var doc = MATH_RENDERER.render( tex == null ? "" : tex );
		final var svg = SvgRasterizer.toSvg( doc.getDocumentElement() );
		html.raw( svg );

Delta	10 lines added, 26 lines removed, 16-line decrease