static createSampleData(fontFamily) {
        const canvas = document.createElement('canvas');
        const ctx = canvas.getContext('2d');
        canvas.style.height = `${16 /* Constants.SAMPLED_CHAR_HEIGHT */}px`;
        canvas.height = 16 /* Constants.SAMPLED_CHAR_HEIGHT */;
        canvas.width = 96 /* Constants.CHAR_COUNT */ * 10 /* Constants.SAMPLED_CHAR_WIDTH */;
        canvas.style.width = 96 /* Constants.CHAR_COUNT */ * 10 /* Constants.SAMPLED_CHAR_WIDTH */ + 'px';
        ctx.fillStyle = '#ffffff';
        ctx.font = `bold ${16 /* Constants.SAMPLED_CHAR_HEIGHT */}px ${fontFamily}`;
        ctx.textBaseline = 'middle';
        let x = 0;
        for (const code of allCharCodes) {
            ctx.fillText(String.fromCharCode(code), x, 16 /* Constants.SAMPLED_CHAR_HEIGHT */ / 2);
            x += 10 /* Constants.SAMPLED_CHAR_WIDTH */;
        }
        return ctx.getImageData(0, 0, 96 /* Constants.CHAR_COUNT */ * 10 /* Constants.SAMPLED_CHAR_WIDTH */, 16 /* Constants.SAMPLED_CHAR_HEIGHT */);
    }
Creates the font sample data, writing to a canvas.