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src/Chart.vala

@@ -49,9 +49,14 @@ namespace CairoChart {
 		public CairoChart.Math math { get; protected set; default = new Math(); }
 		public Cursors cursors { get; protected set; default = new Cursors (); }
 
-		public Chart () {
+		public Color color {
+			private get { return Color(); }
+			set { context.set_source_rgba (value.red, value.green, value.blue, value.alpha); }
+			default = Color();
 		}
 
+		public Chart () { }
+
 		public Chart copy () {
 			var chart = new Chart ();
 			chart.bg_color = this.bg_color;
@@ -96,9 +101,9 @@ namespace CairoChart {
 
 		public virtual void clear () {
 			if (context != null) {
-				set_source_rgba (bg_color);
+				color = bg_color;
 				context.paint();
-				set_source_rgba (Color (0, 0, 0, 1));
+				color = Color (0, 0, 0, 1);
 			}
 		}
 
@@ -138,9 +143,43 @@ namespace CairoChart {
 
 			return true;
 		}
-
+		protected virtual void draw_chart_title () {
-		public virtual void set_source_rgba (Color color) {
+			var sz = title.get_size(context);
-				context.set_source_rgba (color.red, color.green, color.blue, color.alpha);
+			title_height = sz.height + (legend.position == Legend.Position.TOP ? title_indent * 2 : title_indent);
+			cur_y_min += title_height;
+			color = title.color;
+			context.move_to (width/2 - sz.width/2, sz.height + title_indent);
+			title.show(context);
+		}
+		public virtual void draw_selection (Cairo.Rectangle rect) {
+			selection_style.set(this);
+			context.rectangle (rect.x, rect.y, rect.width, rect.height);
+			context.stroke();
+		}
+		protected virtual void draw_horizontal_axes () {
+			for (var si = series.length - 1, nskip = 0; si >=0; --si)
+				series[si].draw_horizontal_axis (si, ref nskip);
+		}
+		protected virtual void draw_vertical_axes () {
+			for (var si = series.length - 1, nskip = 0; si >=0; --si)
+				series[si].draw_vertical_axis (si, ref nskip);
+		}
+		protected virtual void draw_plot_area_border () {
+			color = border_color;
+			context.set_dash(null, 0);
+			context.move_to (plot_x_min, plot_y_min);
+			context.line_to (plot_x_min, plot_y_max);
+			context.line_to (plot_x_max, plot_y_max);
+			context.line_to (plot_x_max, plot_y_min);
+			context.line_to (plot_x_min, plot_y_min);
+			context.stroke ();
+		}
+		protected virtual void draw_series () {
+			for (var si = 0; si < series.length; ++si) {
+				var s = series[si];
+				if (s.zoom_show && s.points.length != 0)
+					s.draw();
+			}
 		}
 
 		public virtual void zoom_in (Cairo.Rectangle rect) {
@@ -201,7 +240,6 @@ namespace CairoChart {
 			rz_y_min = new_rz_y_min;
 			rz_y_max = new_rz_y_max;
 		}
-
 		public virtual void zoom_out () {
 			foreach (var s in series) {
 				s.zoom_show = true;
@@ -221,7 +259,6 @@ namespace CairoChart {
 
 			zoom_first_show = 0;
 		}
-
 		public virtual void move (Point delta) {
 			var d = delta;
 			d.x /= plot_x_max - plot_x_min; d.x *= - 1.0;
@@ -245,21 +282,6 @@ namespace CairoChart {
 			zoom_in (Cairo.Rectangle(){x = xmin + d.x, y = ymin + d.y, width = xmax - xmin, height = ymax - ymin});
 		}
 
-		protected virtual void draw_chart_title () {
-			var sz = title.get_size(context);
-			title_height = sz.height + (legend.position == Legend.Position.TOP ? title_indent * 2 : title_indent);
-			cur_y_min += title_height;
-			set_source_rgba(title.color);
-			context.move_to (width/2 - sz.width/2, sz.height + title_indent);
-			title.show(context);
-		}
-
-		public virtual void draw_selection (Cairo.Rectangle rect) {
-			selection_style.set(this);
-			context.rectangle (rect.x, rect.y, rect.width, rect.height);
-			context.stroke();
-		}
-
 		protected virtual void set_vertical_axes_titles () {
 			for (var si = 0; si < series.length; ++si) {
 				var s = series[si];
@@ -339,35 +361,6 @@ namespace CairoChart {
 			join_calc (false);
 		}
 
-		protected virtual void draw_horizontal_axes () {
-			for (var si = series.length - 1, nskip = 0; si >=0; --si)
-				series[si].draw_horizontal_axis (si, ref nskip);
-		}
-
-		protected virtual void draw_vertical_axes () {
-			for (var si = series.length - 1, nskip = 0; si >=0; --si)
-				series[si].draw_vertical_axis (si, ref nskip);
-		}
-
-		protected virtual void draw_plot_area_border () {
-			set_source_rgba (border_color);
-			context.set_dash(null, 0);
-			context.move_to (plot_x_min, plot_y_min);
-			context.line_to (plot_x_min, plot_y_max);
-			context.line_to (plot_x_max, plot_y_max);
-			context.line_to (plot_x_max, plot_y_min);
-			context.line_to (plot_x_min, plot_y_min);
-			context.stroke ();
-		}
-
-		protected virtual void draw_series () {
-			for (var si = 0; si < series.length; ++si) {
-				var s = series[si];
-				if (s.zoom_show && s.points.length != 0)
-					s.draw();
-			}
-		}
-
 		protected virtual bool x_in_plot_area (double x) {
 			if (math.x_in_range(x, plot_x_min, plot_x_max))
 				return true;

src/Cursor.vala

@@ -375,20 +375,20 @@ namespace CairoChart {
 					var show_time = ccs[ci].show_time;
 					var show_y = ccs[ci].show_y;
 
-					chart.set_source_rgba(chart.bg_color);
+					chart.color = chart.bg_color;
 					chart.context.rectangle (svp.x - size.x / 2, svp.y - size.y / 2, size.x, size.y);
 					chart.context.fill();
 
 					if (show_x) {
-						chart.set_source_rgba(s.axis_x.color);
+						chart.color = s.axis_x.color;
 						var text_t = new Text(s.axis_x.format.printf((LongDouble)point.x), s.axis_x.font_style);
 						chart.context.move_to (svp.x - size.x / 2, svp.y + text_t.get_height(chart.context) / 2);
-						if (chart.joint_x) chart.set_source_rgba (chart.joint_axis_color);
+						if (chart.joint_x) chart.color = chart.joint_axis_color;
 						text_t.show(chart.context);
 					}
 
 					if (show_time) {
-						chart.set_source_rgba(s.axis_x.color);
+						chart.color = s.axis_x.color;
 						string date = "", time = "";
 						s.axis_x.format_date_time(point.x, out date, out time);
 						var text_t = new Text(time, s.axis_x.font_style);
@@ -396,12 +396,12 @@ namespace CairoChart {
 						var y = svp.y + sz.height / 2;
 						if (show_date) y -= sz.height / 2 + s.axis_x.font_indent / 2;
 						chart.context.move_to (svp.x - size.x / 2, y);
-						if (chart.joint_x) chart.set_source_rgba (chart.joint_axis_color);
+						if (chart.joint_x) chart.color = chart.joint_axis_color;
 						text_t.show(chart.context);
 					}
 
 					if (show_date) {
-						chart.set_source_rgba(s.axis_x.color);
+						chart.color = s.axis_x.color;
 						string date = "", time = "";
 						s.axis_x.format_date_time(point.x, out date, out time);
 						var text_t = new Text(date, s.axis_x.font_style);
@@ -409,16 +409,16 @@ namespace CairoChart {
 						var y = svp.y + sz.height / 2;
 						if (show_time) y += sz.height / 2 + s.axis_x.font_indent / 2;
 						chart.context.move_to (svp.x - size.x / 2, y);
-						if (chart.joint_x) chart.set_source_rgba (chart.joint_axis_color);
+						if (chart.joint_x) chart.color = chart.joint_axis_color;
 						text_t.show(chart.context);
 					}
 
 					if (show_y) {
-						chart.set_source_rgba(s.axis_y.color);
+						chart.color = s.axis_y.color;
 						var text_t = new Text(s.axis_y.format.printf((LongDouble)point.y), s.axis_y.font_style);
 						var sz = text_t.get_size(chart.context);
 						chart.context.move_to (svp.x + size.x / 2 - sz.width, svp.y + sz.height / 2);
-						if (chart.joint_y) chart.set_source_rgba (chart.joint_axis_color);
+						if (chart.joint_y) chart.color = chart.joint_axis_color;
 						text_t.show(chart.context);
 					}
 				}

src/Legend.vala

@@ -70,7 +70,7 @@ namespace CairoChart {
 					y0 = (chart.height - height) / 2;
 				break;
 				}
-				chart.set_source_rgba(bg_color);
+				chart.color = bg_color;
 				chart.context.rectangle (x0, y0, width, height);
 				chart.context.fill();
 				border_style.set(chart);
@@ -144,7 +144,7 @@ namespace CairoChart {
 
 					// series title
 					chart.context.move_to (x + line_length, y);
-					chart.set_source_rgba (s.title.color);
+					chart.color = s.title.color;
 					s.title.show(chart.context);
 
 					// series line style

src/Line.vala

@@ -26,7 +26,7 @@ namespace CairoChart {
 			}
 
 			public void set (Chart chart) {
-				chart.set_source_rgba(color);
+				chart.color = color;
 				chart.context.set_line_join(join);
 				chart.context.set_line_cap(cap);
 				chart.context.set_line_width(width);

src/Series.vala

@@ -193,8 +193,8 @@ namespace CairoChart {
 			var joint_x = chart.joint_x;
 
 			for (Float128 x = x_min, x_max = axis_x.zoom_max; chart.math.point_belong (x, x_min, x_max); x += step) {
-				if (joint_x) chart.set_source_rgba(chart.joint_axis_color);
+				if (joint_x) chart.color = chart.joint_axis_color;
-				else chart.set_source_rgba(axis_x.color);
+				else chart.color = axis_x.color;
 				string text = "", time_text = "";
 				switch (axis_x.type) {
 				case Axis.Type.NUMBERS:
@@ -316,8 +316,8 @@ namespace CairoChart {
 				case Axis.Position.HIGH: scr_y = chart.cur_y_min + s.axis_x.font_indent + sz.height; break;
 				}
 				chart.context.move_to(scr_x - sz.width / 2.0, scr_y);
-				chart.set_source_rgba(s.axis_x.color);
+				chart.color = s.axis_x.color;
-				if (chart.joint_x) chart.set_source_rgba(chart.joint_axis_color);
+				if (chart.joint_x) chart.color = chart.joint_axis_color;
 				s.axis_x.title.show(chart.context);
 			}
 
@@ -348,8 +348,8 @@ namespace CairoChart {
 			var joint_y = chart.joint_y;
 
 			for (Float128 y = y_min, y_max = axis_y.zoom_max; chart.math.point_belong (y, y_min, y_max); y += step) {
-				if (joint_y) chart.set_source_rgba(chart.joint_axis_color);
+				if (joint_y) chart.color = chart.joint_axis_color;
-				else chart.set_source_rgba(axis_y.color);
+				else chart.color = axis_y.color;
 				var text = axis_y.format.printf((LongDouble)y);
 				var scr_y = get_scr_y (y);
 				var text_t = new Text(text, axis_y.font_style, axis_y.color);
@@ -444,8 +444,8 @@ namespace CairoChart {
 					chart.context.move_to(scr_x, scr_y + sz.height / 2.0);
 					break;
 				}
-				chart.set_source_rgba(s.axis_y.color);
+				chart.color = s.axis_y.color;
-				if (chart.joint_y) chart.set_source_rgba(chart.joint_axis_color);
+				if (chart.joint_y) chart.color = chart.joint_axis_color;
 				s.axis_y.title.show(chart.context);
 			}
 

test/ChartTest.vala

@@ -437,11 +437,11 @@ int main (string[] args) {
 			var h = text_t.get_height(context);
 			var x0 = chart.plot_x_max - w - 5;
 			var y0 = chart.plot_y_min + h + 5;
-			chart.set_source_rgba(chart.legend.bg_color);
+			chart.color = chart.legend.bg_color;
 			context.rectangle (x0, y0 - h, w, h);
 			context.fill();
 			context.move_to (x0, y0);
-			chart.set_source_rgba(chart.joint_axis_color);
+			chart.color = chart.joint_axis_color;
 			context.show_text(text);
 		}