Advanced Coloring
Overview
There are several ways to color a seat map. The first way is to set colors through the data set. The second way is to set original or custom colors through the coloring methods like fill() and stroke(): in this case it is possible to color all elements of a group differently, depending on the class set in the SVG code. You can also use AnyChart palette or use Color Scale and Color Range.
The sample below demonstrates how an SVG image looks like with the default AnyChart color palette (the SVG image used there is also used in some samples from the Seat Map and Preparing SVG Image articles):
Using SVG Image Colors
The colors in the sample picture are different from those defined in JavaScript (check out the source SVG image to see the original colors). Setting original colors used in the picture is considered in this section, as well as using these colors as a basis for hovering and selecting colors.
To set the colors of the original SVG image, or to set new custom colors, use the fill() and stroke() methods. Though, it is important to remember that not all of the elements in SVG files have the "fill" attribute. Before setting the value to the "fill" field, it is necessary to check if the element has it, and if it does, you should set the fill color to this element. Setting colors through this methods looks like the following:
// sets series fill
series.fill(function () {
var attrs = this.attributes;
if (attrs) return attrs.fill;
});
// sets series stroke
series.stroke(function () {
var attrs = this.attributes;
// if the stroke attribute exists in the SVG file, then color it with a color set in the document
return attrs ? attrs.stroke : this.sourceColor;
});
To change the interactivity colors (colors of elements or groups on hover and select), use the following methods: hoverFill(), hoverStroke(), selectFill() and selectStroke()
// set the hoverFill color
series.hoverFill(function(){
var attrs = this.attributes;
return attrs ? anychart.color.lighten(attrs.fill, 0.5) : this.sourceColor;
});
// set the selectFill color
series.selectFill(function(){
var attrs = this.attributes;
return attrs ? anychart.color.darken(attrs.fill, 0.2) : this.sourceColor;
});
// sets stroke series
series.hoverStroke(function () {
var attrs = this.attributes;
return attrs ? attrs.stroke : this.sourceColor;
});
// sets stroke series
series.selectStroke(function () {
var attrs = this.attributes;
return attrs ? attrs.stroke : this.sourceColor;
});
Selective Coloring
It is also possible to change the colors of separate elements or of parts of a group if there are any. However, it is necessary to know the group's structure and the classes set to those elements. In case no classes are set, it is necessary to set them, as the classes help to define the elements.
<g id="hotplate">
<rect x="156.531" y="503.167" fill="#FFFFFF" stroke="#000000" stroke-miterlimit="10" width="40" height="33"/>
<circle class="inner_elements" fill="#FFFFFF" stroke="#000000" stroke-miterlimit="10" cx="167.627" cy="513.097" r="4.929"/>
<circle class="inner_elements" fill="#FFFFFF" stroke="#000000" stroke-miterlimit="10" cx="186.149" cy="513.097" r="4.929"/>
<circle class="inner_elements" fill="#FFFFFF" stroke="#000000" stroke-miterlimit="10" cx="167.627" cy="527.477" r="4.929"/>
<circle class="inner_elements" fill="#FFFFFF" stroke="#000000" stroke-miterlimit="10" cx="186.149" cy="527.477" r="4.929"/>
</g>
// set the hoverFill color
series.hoverFill(function(){
var attrs = this.attributes;
if (attrs) {
// get the class
var clas = attrs.class;
switch (clas) {
case "inner_elements" :
return "red";
default:
return anychart.color.lighten(attrs.fill, 0.5);
}
} else {
return this.sourceColor;
}
});
Palette
Palette is a color scheme which is used to set colors to the series of a chart. Using the palette() method, it is possible to set the default palette or to define custom colors. Note that this method is most useful when the SVG image contains several series.
In the next sample we group seats into several series to work with rows, each seat has its own ID. The palette is formed out of two different hues: the original and the resulting colors of the 8-step gradient
palette = anychart.palettes.rangeColors();
palette.items(["#F44336", "#FCEF86"]);
palette.count(8);
// setting custom colors to the chart palette
chart.palette(palette);
Color Scale and Color Range
It is possible to add Color Range and use Color Scale in AnyChart Seat Maps. Color Range looks like a range bar, colored as a gradient or like a number of colored boxes, each presenting a range of values. It is rather useful in identifying the value that each point on a map represents.
To make it work properly, set the colors and the type of the Color Scale. You can find information about adjusting Color Scale in the Color Scale & Color Range articles.
In the next sample, the ranges are set as an array. Each range has its own color defined in the data set.
// set the ranges for the scale and corresponding colors
colorScale = anychart.scales.ordinalColor();
colorScale.ranges([
{from: 0, to: 3.5, color: "#FCEF86"},
{from: 4, to: 5.5, color: "#EC8A00"},
{from: 6, to: 7.5, color: "#1368C4"},
{from: 8, to: 12, color: "#9F0856"}
]);
After being created, a Color Scale should be bound to a series:
// set color scale to a series
series.colorScale(colorScale);
So, each series on a map is able to have its own Color Scale, which can be quite useful in some situations.
Color Scale and Color Range are different objects. Creating and enabling a Color Scale doesn't mean that a Color Range automatically appears in the chart. To add a Color Range, use the colorRange() or enabled() method of a Color Range control.
// create and enable the colorRange
chart.colorRange(true);
There are some other ways to set colors for a Color Scale: for example, it is possible to set the gradient mode (to learn more, see the Color Range article).
Using a color gradient can make the chart more illustrative, and in this case there is no need to set a color for each value range.
In the sample below the ranges are set without colors for each of them, but the colors of the Color Scale are defined as a progression of a hue through the singleHueProgression() function.
// set the ranges for the scale
currentColorScale = anychart.scales.ordinalColor();
currentColorScale.ranges([
{from: 0, to: 3.5},
{from: 4, to: 5.5},
{from: 6, to: 7.5},
{from: 8, to: 12}
]);
//set the color progression
var colors = anychart.color.singleHueProgression("#336666");
// define the colors
currentColorScale.colors(colors);
series.сolorScale(currentColorScale);
// create and enable the Color Range
var colorrange = chart.colorRange();
colorrange.enabled(true);