namespace CairoChart {

	/**
	 * ``Chart`` axis.
	 */
	public class Axis {

		protected unowned Chart chart;
		protected unowned Series ser;
		protected string _format = "%.2Lf";
		protected string _date_format = "%Y.%m.%d";
		protected string _time_format = "%H:%M:%S";
		protected int _dsec_signs = 2; // 2 signs = centiseconds

		/**
		 * ``Axis`` title.
		 */
		public Text title;

		/**
		 * ``Axis`` range/limits.
		 */
		public Range range = new Range();

		/**
		 * ``Axis`` relative range/limits.
		 */
		public Range place = new Range();

		/**
		 * Data type.
		 */
		public enum DType {
			/**
			 * Float128 numbers.
			 */
			NUMBERS = 0,

			/**
			 * Date/Time.
			 */
			DATE_TIME
		}

		/**
		 * Data type.
		 */
		public DType dtype;

		/**
		 * ``Axis`` scale type.
		 */
		public enum Scale {
			/**
			 * Linear scale.
			 */
			LINEAR = 0,

			/**
			 * Logarithmic scale.
			 */
			// LOGARITHMIC,
		}

		/**
		 * Scale type.
		 */
		public Scale scale;

		/**
		 * ``Axis`` position.
		 */
		public enum Position {
			/**
			 * Bottom/Left ``Axis``.
			 */
			LOW = 0,

			/**
			 * Top/Right ``Axis``.
			 */
			HIGH = 1,

			/**
			 * 2 ``Axes``.
			 */
			BOTH = 2
		}

		/**
		 * Position.
		 */
		public Position position = Position.LOW;

		/**
		 * Float128 numbers print string format.
		 */
		public virtual string format {
			get { return _format; }
			set {
				// TODO: check format
				_format = value;
			}
			default = "%.2Lf";
		}

		/**
		 * Date print string format.
		 */
		public virtual string date_format {
			get { return _date_format; }
			set {
				// TODO: check format
				_date_format = value;
			}
			default = "%Y.%m.%d";
		}

		/**
		 * Time print string format.
		 */
		public virtual string time_format {
			get { return _time_format; }
			set {
				// TODO: check format
				_time_format = value;
			}
			default = "%H:%M:%S";
		}

		/**
		 * Number of second's signs after point.
		 *
		 * 2 signs means centiseconds, 3 signs means milliseconds, etc...
		 */
		public virtual int dsec_signs {
			get { return _dsec_signs; }
			set {
				// TODO: check format
				_dsec_signs = value;
			}
			default = 2;
		}

		/**
		 * ``Axis`` Font style.
		 */
		public Font font = new Font ();

		/**
		 * ``Axis`` color.
		 */
		public Color color = Color ();

		/**
		 * ``Axis`` line style.
		 */
		public LineStyle line_style = LineStyle ();

		/**
		 * Number of equally placed points to evaluate records sizes.
		 */
		public int nrecords = 128;

		/**
		 * Constructs a new ``Axis``.
		 * @param chart ``Chart`` instance.
		 * @param ser ``Series`` instance.
		 */
		public Axis (Chart chart, Series ser) {
			this.chart = chart;
			this.ser = ser;
			title = new Text (chart, "");
		}

		/**
		 * Gets a copy of the ``Axis``.
		 */
		public virtual Axis copy () {
			var axis = new Axis (chart, ser);
			axis._date_format = this._date_format;
			axis._dsec_signs = this._dsec_signs;
			axis._format = this._format;
			axis._time_format = this._time_format;
			axis.color = this.color;
			axis.font = this.font.copy();
			axis.line_style = this.line_style;
			axis.range = this.range.copy();
			axis.place = this.place.copy();
			axis.position = this.position;
			axis.scale = this.scale;
			axis.title = this.title.copy();
			axis.dtype = this.dtype;
			axis.nrecords = this.nrecords;
			return axis;
		}

		/**
		 * Prints date/time to strings with a current formats.
		 * @param date returns formatted date string.
		 * @param time returns formatted time string.
		 */
		public virtual void print_dt (Float128 x, out string date, out string time) {
			date = time = "";
			var dt = new DateTime.from_unix_utc((int64)x);
			date = dt.format(date_format);
			var dsec_str =
				("%."+(dsec_signs.to_string())+"Lf").printf((LongDouble)(x - (int64)x)).offset(1);
			time = dt.format(time_format) + dsec_str;
		}

		/**
		 * Zooms out ``Axis``.
		 */
		public virtual void zoom_out () {
			range.zoom_out();
			place.zoom_out();
		}
//--------------------------------------------------------------------


		/**
		 * Joins equal axes.
		 * @param is_x is this X-axis or not.
		 * @param nskip returns number of series to skip printing.
		 */
		public virtual void join_axes (bool is_x, ref int nskip) {
			Axis axis = this;
			if (!ser.zoom_show) return;
			if (nskip != 0) {--nskip; return;}
			var max_rec_width = 0.0, max_rec_height = 0.0;
			calc_rec_sizes (axis, out max_rec_width, out max_rec_height, is_x);
			var max_font_spacing = is_x ? axis.font.vspacing : axis.font.hspacing;
			var max_axis_font_width = axis.title.text == "" ? 0 : axis.title.width + axis.font.hspacing;
			var max_axis_font_height = axis.title.text == "" ? 0 : axis.title.height + axis.font.vspacing;

			var si = Math.find_arr<Series>(chart.series, ser);
			if (si == -1) return;

			if (is_x)
				join_relative_x_axes (si, true, ref max_rec_width, ref max_rec_height, ref max_font_spacing, ref max_axis_font_height, ref nskip);
			else
				join_relative_y_axes (si, true, ref max_rec_width, ref max_rec_height, ref max_font_spacing, ref max_axis_font_width, ref nskip);

			// for 4.2. Cursor values for joint X axis
			if (si == chart.zoom_1st_idx && chart.cursors.has_crossings) {
				switch (chart.cursors.style.orientation) {
				case Cursors.Orientation.VERTICAL:
					if (is_x && chart.joint_x) {
						var tmp = max_rec_height + axis.font.vspacing;
						switch (axis.position) {
						case Axis.Position.LOW: chart.plarea.y1 -= tmp; break;
						case Axis.Position.HIGH: chart.plarea.y0 += tmp; break;
						}
					}
					break;
				case Cursors.Orientation.HORIZONTAL:
					if (!is_x && chart.joint_y) {
						var tmp = max_rec_width + font.hspacing;
						switch (position) {
						case Axis.Position.LOW: chart.plarea.x0 += tmp; break;
						case Axis.Position.HIGH: chart.plarea.x1 -= tmp; break;
						}
					}
					break;
				}
			}
			if (is_x && (!chart.joint_x || si == chart.zoom_1st_idx)) {
				var tmp = max_rec_height + max_font_spacing + max_axis_font_height;
				switch (axis.position) {
				case Axis.Position.LOW: chart.plarea.y1 -= tmp; break;
				case Axis.Position.HIGH: chart.plarea.y0 += tmp; break;
				}
			}
			if (!is_x && (!chart.joint_y || si == chart.zoom_1st_idx)) {
				var tmp = max_rec_width + max_font_spacing + max_axis_font_width;
				switch (position) {
				case Axis.Position.LOW: chart.plarea.x0 += tmp; break;
				case Axis.Position.HIGH: chart.plarea.x1 -= tmp; break;
				}
			}
		}

		/**
		 * Draws horizontal axis.
		 * @param nskip number of series to skip printing.
		 */
		public virtual void draw_horizontal_axis (ref int nskip) {
			if (!ser.zoom_show) return;

			var si = Math.find_arr<Series>(chart.series, ser);
			if (si == -1) return;

			if (chart.joint_x && si != chart.zoom_1st_idx) return;

			// 1. Detect max record width/height by axis.nrecords equally selected points using format.
			double max_rec_width, max_rec_height;
			calc_rec_sizes (this, out max_rec_width, out max_rec_height, true);

			// 2. Calculate maximal available number of records, take into account the space width.
			long max_nrecs = (long) (chart.plarea.width * place.zrange / max_rec_width);

			// 3. Calculate grid step.
			Float128 step = Math.calc_round_step (range.zrange / max_nrecs, dtype == Axis.DType.DATE_TIME);
			if (step > range.zrange)
				step = range.zrange;

			// 4. Calculate x_min (range.zmin / step, round, multiply on step, add step if < range.zmin).
			Float128 x_min = 0;
			if (step >= 1) {
				int64 x_min_nsteps = (int64) (range.zmin / step);
				x_min = x_min_nsteps * step;
			} else {
				int64 round_axis_x_min = (int64)range.zmin;
				int64 x_min_nsteps = (int64) ((range.zmin - round_axis_x_min) / step);
				x_min = round_axis_x_min + x_min_nsteps * step;
			}
			if (x_min < range.zmin) x_min += step;

			// 4.2. Cursor values for joint X axis
			if (chart.joint_x && chart.cursors.style.orientation == Cursors.Orientation.VERTICAL && chart.cursors.has_crossings) {
				var tmp = max_rec_height + font.vspacing;
				switch (position) {
				case Axis.Position.LOW: chart.evarea.y1 -= tmp; break;
				case Axis.Position.HIGH:  chart.evarea.y0 += tmp; break;
				}
			}

			// 4.5. Draw Axis title
			if (title.text != "") {
				var scr_x = chart.plarea.x0 + chart.plarea.width * (place.zmin + place.zmax) / 2;
				var scr_y = 0.0;
				switch (position) {
				case Axis.Position.LOW: scr_y = chart.evarea.y1 - font.vspacing; break;
				case Axis.Position.HIGH: scr_y = chart.evarea.y0 + font.vspacing + title.height; break;
				}
				chart.ctx.move_to(scr_x - title.width / 2, scr_y);
				chart.color = color;
				if (chart.joint_x) chart.color = chart.joint_color;
				title.show();
			}

			draw_horizontal_records (step, max_rec_height, x_min);

			chart.ctx.stroke ();

			var tmp1 = 0.0, tmp2 = 0.0, tmp3 = 0.0, tmp4 = 0.0;
			join_relative_x_axes (si, false, ref tmp1, ref tmp2, ref tmp3, ref tmp4, ref nskip);

			if (nskip != 0) {--nskip; return;}

			var tmp = max_rec_height + font.vspacing + (title.text == "" ? 0 : title.height + font.vspacing);
			switch (position) {
			case Axis.Position.LOW: chart.evarea.y1 -= tmp; break;
			case Axis.Position.HIGH: chart.evarea.y0 += tmp; break;
			}
		}

		/**
		 * Draws vertical axis.
		 * @param nskip number of series to skip printing.
		 */
		public virtual void draw_vertical_axis (ref int nskip) {
			if (!ser.zoom_show) return;

			var si = Math.find_arr<Series>(chart.series, ser);
			if (si == -1) return;

			if (chart.joint_y && si != chart.zoom_1st_idx) return;
			// 1. Detect max record width/height by axis.nrecords equally selected points using format.
			double max_rec_width, max_rec_height;
			calc_rec_sizes (this, out max_rec_width, out max_rec_height, false);

			// 2. Calculate maximal available number of records, take into account the space width.
			long max_nrecs = (long) (chart.plarea.height * place.zrange / max_rec_height);

			// 3. Calculate grid step.
			Float128 step = Math.calc_round_step (range.zrange / max_nrecs);
			if (step > range.zrange)
				step = range.zrange;

			// 4. Calculate y_min (range.zmin / step, round, multiply on step, add step if < range.zmin).
			Float128 y_min = 0;
			if (step >= 1) {
				int64 y_min_nsteps = (int64) (range.zmin / step);
				y_min = y_min_nsteps * step;
			} else {
				int64 round_axis_y_min = (int64)range.zmin;
				int64 y_min_nsteps = (int64) ((range.zmin - round_axis_y_min) / step);
				y_min = round_axis_y_min + y_min_nsteps * step;
			}
			if (y_min < range.zmin) y_min += step;

			// 4.2. Cursor values for joint Y axis
			if (chart.joint_y && chart.cursors.style.orientation == Cursors.Orientation.HORIZONTAL && chart.cursors.has_crossings) {
				var tmp = max_rec_width + font.hspacing;
				switch (position) {
				case Axis.Position.LOW: chart.evarea.x0 += tmp; break;
				case Axis.Position.HIGH: chart.evarea.x1 -= tmp; break;
				}
			}

			// 4.5. Draw Axis title
			if (title.text != "") {
				var scr_y = chart.plarea.y0 + chart.plarea.height * (1 - (place.zmin + place.zmax) / 2);
				switch (position) {
				case Axis.Position.LOW:
					var scr_x = chart.evarea.x0 + font.hspacing + title.width;
					chart.ctx.move_to(scr_x, scr_y + title.height / 2);
					break;
				case Axis.Position.HIGH:
					var scr_x = chart.evarea.x1 - font.hspacing;
					chart.ctx.move_to(scr_x, scr_y + title.height / 2);
					break;
				}
				chart.color = color;
				if (chart.joint_y) chart.color = chart.joint_color;
				title.show();
			}

			draw_vertical_records (step, max_rec_width, y_min);

			chart.ctx.stroke ();

			var tmp1 = 0.0, tmp2 = 0.0, tmp3 = 0.0, tmp4 = 0.0;
			join_relative_y_axes (si, false, ref tmp1, ref tmp2, ref tmp3, ref tmp4, ref nskip);

			if (nskip != 0) {--nskip; return;}

			var tmp = max_rec_width + font.hspacing + (title.text == "" ? 0 : title.width + font.hspacing);
			switch (position) {
			case Axis.Position.LOW: chart.evarea.x0 += tmp; break;
			case Axis.Position.HIGH: chart.evarea.x1 -= tmp; break;
			}
		}

		/**
		 * Gets compact placement X-position on the screen.
		 * @param x real ``Series`` X-value.
		 * @param text to place on the screen.
		 */
		public virtual double compact_rec_x_pos (Float128 x, Text text) {
			return get_scr_x(x) - text.width / 2
			       - text.width * (x - (range.zmin + range.zmax) / 2) / range.zrange;
		}

		/**
		 * Gets compact placement Y-position on the screen.
		 * @param y real ``Series`` Y-value.
		 * @param text to place on the screen.
		 */
		public virtual double compact_rec_y_pos (Float128 y, Text text) {
			return get_scr_y(y) + text.height / 2
			       + text.height * (y - (range.zmin + range.zmax) / 2) / range.zrange;
		}

		/**
		 * Gets screen X-position by real ``Series`` X-value.
		 * @param x real ``Series`` X-value.
		 */
		public virtual double get_scr_x (Float128 x) {
			return chart.plarea.x0 + chart.plarea.width * (place.zmin + (x - range.zmin) / range.zrange * place.zrange);
		}

		/**
		 * Gets screen Y-position by real ``Series`` Y-value.
		 * @param y real ``Series`` Y-value.
		 */
		public virtual double get_scr_y (Float128 y) {
			return chart.plarea.y0 + chart.plarea.height * (1 - (place.zmin + (y - range.zmin) / range.zrange * place.zrange));
		}

		/**
		 * Gets real ``Series`` X-value by plot area screen X-position.
		 * @param scr_x screen X-position.
		 */
		public virtual Float128 get_real_x (double scr_x) {
			return range.zmin + ((scr_x - chart.plarea.x0) / chart.plarea.width - place.zmin) * range.zrange / place.zrange;
		}

		/**
		 * Gets real ``Series`` Y-value by plot area screen Y-position.
		 * @param scr_y screen Y-position.
		 */
		public virtual Float128 get_real_y (double scr_y) {
			return range.zmin + ((chart.plarea.y1 - scr_y) / chart.plarea.height - place.zmin) * range.zrange / place.zrange;
		}

		protected virtual void calc_rec_sizes (Axis axis, out double max_rec_width, out double max_rec_height, bool horizontal = true) {
			max_rec_width = max_rec_height = 0;
			for (var i = 0; i < axis.nrecords; ++i) {
				Float128 x = (int64)(axis.range.zmin + axis.range.zrange / axis.nrecords * i) + 1/3.0;
				switch (axis.dtype) {
				case Axis.DType.NUMBERS:
					var text = new Text (chart, axis.format.printf((LongDouble)x) + (horizontal ? "_" : ""), axis.font);
					max_rec_width = double.max (max_rec_width, text.width);
					max_rec_height = double.max (max_rec_height, text.height);
					break;
				case Axis.DType.DATE_TIME:
					string date, time;
					axis.print_dt(x, out date, out time);

					var h = 0.0;
					if (axis.date_format != "") {
						var text = new Text (chart, date + (horizontal ? "_" : ""), axis.font);
						max_rec_width = double.max (max_rec_width, text.width);
						h = text.height;
					}
					if (axis.time_format != "") {
						var text = new Text (chart, time + (horizontal ? "_" : ""), axis.font);
						max_rec_width = double.max (max_rec_width, text.width);
						h += text.height;
					}
					max_rec_height = double.max (max_rec_height, h);
					break;
				}
			}
		}

		protected virtual void join_relative_x_axes (int si,
		                                             bool calc_max_values,
		                                             ref double max_rec_width,
		                                             ref double max_rec_height,
		                                             ref double max_font_spacing,
		                                             ref double max_axis_font_height,
		                                             ref int nskip) {
			for (int sj = si - 1; sj >= 0; --sj) {
				var s2 = chart.series[sj];
				if (!s2.zoom_show) continue;
				bool has_intersection = false;
				for (int sk = si; sk > sj; --sk) {
					var s3 = chart.series[sk];
					if (!s3.zoom_show) continue;
					if (Math.coord_cross(s2.axis_x.place.zmin, s2.axis_x.place.zmax, s3.axis_x.place.zmin, s3.axis_x.place.zmax)
					    || s2.axis_x.position != s3.axis_x.position
					    || s2.axis_x.dtype != s3.axis_x.dtype) {
						has_intersection = true;
						break;
					}
				}
				if (!has_intersection) {
					if (calc_max_values) {
						var tmp_max_rec_width = 0.0, tmp_max_rec_height = 0.0;
						calc_rec_sizes (s2.axis_x, out tmp_max_rec_width, out tmp_max_rec_height, true);
						max_rec_width = double.max (max_rec_width, tmp_max_rec_width);
						max_rec_height = double.max (max_rec_height, tmp_max_rec_height);
						max_font_spacing = double.max (max_font_spacing, s2.axis_x.font.vspacing);
						max_axis_font_height = double.max (max_axis_font_height, s2.axis_x.title.text == "" ? 0 :
						                                   s2.axis_x.title.height + font.vspacing);
					}
					++nskip;
				} else {
					break;
				}
			}
		}

		protected virtual void join_relative_y_axes (int si,
		                                             bool calc_max_values,
		                                             ref double max_rec_width,
		                                             ref double max_rec_height,
		                                             ref double max_font_spacing,
		                                             ref double max_axis_font_width,
		                                             ref int nskip) {
			for (int sj = si - 1; sj >= 0; --sj) {
				var s2 = chart.series[sj];
				if (!s2.zoom_show) continue;
				bool has_intersection = false;
				for (int sk = si; sk > sj; --sk) {
					var s3 = chart.series[sk];
					if (!s3.zoom_show) continue;
					if (Math.coord_cross(s2.axis_y.place.zmin, s2.axis_y.place.zmax, s3.axis_y.place.zmin, s3.axis_y.place.zmax)
					    || s2.axis_y.position != s3.axis_y.position
					    || s2.axis_y.dtype != s3.axis_y.dtype) {
						has_intersection = true;
						break;
					}
				}
				if (!has_intersection) {
					var tmp_max_rec_width = 0.0, tmp_max_rec_height = 0.0;
					calc_rec_sizes (s2.axis_y, out tmp_max_rec_width, out tmp_max_rec_height, false);
					max_rec_width = double.max (max_rec_width, tmp_max_rec_width);
					max_rec_height = double.max (max_rec_height, tmp_max_rec_height);
					max_font_spacing = double.max (max_font_spacing, s2.axis_y.font.hspacing);
					max_axis_font_width = double.max (max_axis_font_width, s2.axis_y.title.text == "" ? 0
					                                   : s2.axis_y.title.width + font.hspacing);
					++nskip;
				} else {
					break;
				}
			}
		}

		protected virtual void draw_horizontal_records (Float128 step, double max_rec_height, Float128 x_min) {
			// 5. Draw records, update cur_{x,y}_{min,max}.
			var ctx = chart.ctx;
			var joint_x = chart.joint_x;

			for (Float128 x = x_min, x_max = range.zmax; Math.point_belong (x, x_min, x_max); x += step) {
				if (joint_x) chart.color = chart.joint_color;
				else chart.color = color;
				string text = "", time_text = "";
				switch (dtype) {
				case Axis.DType.NUMBERS: text = format.printf((LongDouble)x); break;
				case Axis.DType.DATE_TIME: print_dt(x, out text, out time_text); break;
				}
				var scr_x = get_scr_x (x);
				var text_t = new Text(chart, text, font, color);

				switch (position) {
				case Axis.Position.LOW:
					var print_y = chart.evarea.y1 - font.vspacing - (title.text == "" ? 0 : title.height + font.vspacing);
					var print_x = compact_rec_x_pos (x, text_t);
					ctx.move_to (print_x, print_y);
					switch (dtype) {
					case Axis.DType.NUMBERS:
						text_t.show();
						break;
					case Axis.DType.DATE_TIME:
						if (date_format != "") text_t.show();
						var time_text_t = new Text(chart, time_text, font, color);
						print_x = compact_rec_x_pos (x, time_text_t);
						ctx.move_to (print_x, print_y - (date_format == "" ? 0 : text_t.height + font.vspacing));
						if (time_format != "") time_text_t.show();
						break;
					}
					// 6. Draw grid lines to the ser.axis_y.place.zmin.
					var grid_style = ser.grid.style;
					if (joint_x) grid_style.color = Color(0, 0, 0, 0.5);
					grid_style.apply(chart);
					double y = chart.evarea.y1 - max_rec_height - font.vspacing - (title.text == "" ? 0 : title.height + font.vspacing);
					ctx.move_to (scr_x, y);
					if (joint_x)
						ctx.line_to (scr_x, chart.plarea.y0);
					else
						ctx.line_to (scr_x, double.min (y, chart.plarea.y0 + chart.plarea.height * (1 - ser.axis_y.place.zmax)));
					break;
				case Axis.Position.HIGH:
					var print_y = chart.evarea.y0 + max_rec_height + font.vspacing + (title.text == "" ? 0 : title.height + font.vspacing);
					var print_x = compact_rec_x_pos (x, text_t);
					ctx.move_to (print_x, print_y);

					switch (dtype) {
					case Axis.DType.NUMBERS:
						text_t.show();
						break;
					case Axis.DType.DATE_TIME:
						if (date_format != "") text_t.show();
						var time_text_t = new Text(chart, time_text, font, color);
						print_x = compact_rec_x_pos (x, time_text_t);
						ctx.move_to (print_x, print_y - (date_format == "" ? 0 : text_t.height + font.vspacing));
						if (time_format != "") time_text_t.show();
						break;
					}
					// 6. Draw grid lines to the ser.axis_y.place.zmax.
					var grid_style = ser.grid.style;
					if (joint_x) grid_style.color = Color(0, 0, 0, 0.5);
					grid_style.apply(chart);
					double y = chart.evarea.y0 + max_rec_height + font.vspacing + (title.text == "" ? 0 : title.height + font.vspacing);
					ctx.move_to (scr_x, y);
					if (joint_x)
						ctx.line_to (scr_x, chart.plarea.y1);
					else
						ctx.line_to (scr_x, double.max (y, chart.plarea.y0 + chart.plarea.height * (1 - ser.axis_y.place.zmin)));
					break;
				}
			}
		}

		protected virtual void draw_vertical_records (Float128 step, double max_rec_width, Float128 y_min) {
			// 5. Draw records, update cur_{x,y}_{min,max}.
			var ctx = chart.ctx;
			var joint_y = chart.joint_y;

			for (Float128 y = y_min, y_max = range.zmax; Math.point_belong (y, y_min, y_max); y += step) {
				if (joint_y) chart.color = chart.joint_color;
				else chart.color = color;
				var text = format.printf((LongDouble)y);
				var scr_y = get_scr_y (y);
				var text_t = new Text(chart, text, font, color);

				switch (position) {
				case Axis.Position.LOW:
					ctx.move_to (chart.evarea.x0 + max_rec_width - text_t.width + font.hspacing
					                 + (title.text == "" ? 0 : title.width + font.hspacing),
					                 compact_rec_y_pos (y, text_t));
					text_t.show();
					// 6. Draw grid lines to the ser.axis_x.place.zmin.
					var grid_style = ser.grid.style;
					if (joint_y) grid_style.color = Color(0, 0, 0, 0.5);
					grid_style.apply(chart);
					double x = chart.evarea.x0 + max_rec_width + font.hspacing + (title.text == "" ? 0 : title.width + font.hspacing);
					ctx.move_to (x, scr_y);
					if (joint_y)
						ctx.line_to (chart.plarea.x1, scr_y);
					else
						ctx.line_to (double.max (x, chart.plarea.x0 + chart.plarea.width * ser.axis_x.place.zmax), scr_y);
					break;
				case Axis.Position.HIGH:
					ctx.move_to (chart.evarea.x1 - text_t.width - font.hspacing
					                 - (title.text == "" ? 0 : title.width + font.hspacing),
					                 compact_rec_y_pos (y, text_t));
					text_t.show();
					// 6. Draw grid lines to the ser.axis_x.place.zmax.
					var grid_style = ser.grid.style;
					if (joint_y) grid_style.color = Color(0, 0, 0, 0.5);
					grid_style.apply(chart);
					double x = chart.evarea.x1 - max_rec_width - font.hspacing - (title.text == "" ? 0 : title.width + font.hspacing);
					ctx.move_to (x, scr_y);
					if (joint_y)
						ctx.line_to (chart.plarea.x0, scr_y);
					else
						ctx.line_to (double.min (x, chart.plarea.x0 + chart.plarea.width * ser.axis_x.place.zmin), scr_y);
					break;
				}
			}
		}
	}
}