Astrolog can generate Scalable Vector Graphics (SVG) files for its chart displays. SVG files can be viewed in a Web browser directly, or embedded within HTML files as seen here. Graphics will be smooth instead of pixelated, and one can resize the browser window and the chart will enlarge or shrink appropriately. Create a SVG file with the -XV switch, or in the Windows version with the "File / Export Vector Format / Export Chart SVG" menu command.