> ## Documentation Index > Fetch the complete documentation index at: https://docs.omni.co/llms.txt > Use this file to discover all available pages before exploring further. # Build X/Y charts with layers > Use layers to control the mark, stacking, color, size, and labels of each measure in a bar, line, area, or scatter chart. Layers give each measure in an X/Y chart its own settings. Every measure you plot on the left or right axis becomes a layer, and each layer has its own mark type, stacking, color, size, and labels. You can draw one measure as bars and another as a line, color one measure by a dimension and leave the other a single color, or put measures on separate axes with independent scales. A bar chart of order counts stacked by status, with a product count line on the right axis ## Requirements Layers must be turned on for your organization. To turn on layers, contact Omni support. Layers apply to X/Y charts: bar, line, area, and scatter. Other chart types, such as tables, pie charts, and maps, don't use layers. When enabled, new X/Y charts use layers automatically. Existing charts keep the classic editor until you move them to layers. Refer to [Switch between the layers and classic editors](/visualize-present/visualizations/layers/switch-editors) to move an existing chart to layers, or to move a chart back. ## How layers work Each measure on the Y-axis is one layer. A chart with one Y-axis shows a single **Y-Axis** section. When you drag a field over it, or when the chart has a right axis, the section splits into **Left-Axis** and **Right-Axis**, and each axis has its own scale. The first layer in a list draws on top. Drag a layer by its handle to change the order. A layer that stacks, such as a bar layer colored by `Status`, stacks only its own segments. Separate layers never stack on each other. To stack or group several measures together, put them in one [Measure values](/visualize-present/visualizations/layers/measure-names-values) layer. ## Chart options When a chart uses layers, the **Chart options** panel has two tabs: * **Chart** - The axes, the layers, Small multiples, Tooltip, Measure values, and Available fields * **Styles** - The chart palette and the legends The Chart tab with an X-axis, a left-axis layer stacked by status, and a right-axis layer ### Add and change fields You can drag fields to the axes and other sections. You can also use these controls: * Click **+** in a section header, or click an empty **Add a field** slot, to pick a field from a list. * Right-click a field, or open its menu, to use these options: * **Field properties...** - Opens the field's title, format, and analytics settings, such as regression lines and moving averages * **Aggregation** - Changes how the field aggregates * **Switch to...** - Replaces the field with another field in place * Click the **X** on a field to remove it. ### Layer settings Each layer has these rows: | Row | What it controls | | --------- | --------------------------------------------------------------------------------------------------------------------------------------------- | | **Mark** | The mark type: **Area**, **Bar**, **Line**, or **Scatter**. A **Stacking** select displays next to the mark when the layer has a color field. | | **Color** | **Single color**, or a field that colors the layer's segments | | **Size** | **Fixed size**, or a field that sets the size of each point. This row displays only for **Scatter** layers. | | **Label** | The data labels for the layer. Pick any field to label the layer with it. | Click the icon at the end of a row to open more options for that row. The Line options popover with Points, Stroke, Width, Interpolation, and Opacity settings ### Change every layer at once When a chart has two or more layers, an **All layers** header displays above them. Open the header's menu to set the same value on every layer. A value set from **All layers** replaces the value on each layer. The All layers menu with the Set color submenu open ## Stacking A layer can stack when it has a color field. For a Measure values layer, the color field is usually **Measure names**. The **Stacking** select displays next to the layer's mark only when the layer has a color field. | Option | Result | Available for | | ------------- | ---------------------------------------------------- | ------------- | | **Stacked** | Segments stack on top of each other | All marks | | **Stacked %** | Segments stack and show each segment's share of 100% | All marks | | **Grouped** | Segments display side by side | Bar | | **Overlay** | Segments draw on top of each other | All marks | Bar and area layers stack by default. Line and scatter layers overlay by default. A chart with two or more measure layers and no color field overlays the layers. To stack the measures, move them into [Measure values](/visualize-present/visualizations/layers/measure-names-values). ### Stack order For a **Stacked** or **Stacked %** layer, open the mark options to control the order of the segments: * **Sort stack by** - The segment order: * **Label** - Alphabetical by the color field's values * **Segment value** - By each segment's value within its own stack. Not available for area or line layers. * **Overall sum** - By each segment's total across all stacks * **Unsorted** - The order of the query results * **Sort order** - Ascending or descending, for example **Ascending (A to Z)** or **Descending (Z to A)**. This setting doesn't display for **Unsorted**. The Mark options popover with Stacking, Sort stack by, and Sort order settings ### Percentage axes Layers on one axis share that axis's scale. The axis shows percentages only when every layer on it uses **Stacked %**. If you mix **Stacked %** with another option on one axis, a warning icon displays on the layer. The percentage layer's values run from 0 to 1 on the same scale as the other layers, so it's squashed at the bottom of the chart. ## Color and legends ### One color setup per field Color settings belong to the field, not to the layer. If two layers color by `Country`, they share one set of colors and one legend. A change to the colors from one layer also changes the other layer. Two layers that both color by Country ### Chart palette The **Styles** tab has the **Default chart palette** for the chart. All layers take colors from this palette unless a layer's color field has its own palette. Omni assigns palette colors in this order, so that layers don't duplicate colors: 1. Layers without a color field take the first colors, one each. 2. Each color field takes the next batch of colors, one for each of its values. A color that you set by hand, or a color from the model's [`colors` parameter](/modeling/dimensions/parameters/colors), keeps its place and doesn't move the other colors. ### Legends The **Styles** tab also lists each legend on the chart. A chart has one legend for each color field and each size field. When a chart has two or more layers, the layers without a color field share one **Series** legend, which has no title by default. The Styles tab with the default chart palette and legend settings for Country and Series #### Filter with the legend Legends in the chart are interactive. Click an item in a legend to show only that item. Cmd+click (Mac) or Ctrl+click (Windows) to select more than one item. When you select items in one legend, layers that belong to other legends are hidden until you clear the selection. ## Labels and totals Labels are set per layer. Pick a field in a layer's **Label** row to label that layer. The field doesn't have to be the layer's measure. For a stacked layer, the label options include **Simple totals**, which labels the total of each stack. Simple totals are calculated per layer. To total several measures, put them in one Measure values layer and turn on **Simple totals** for that layer. The Label options popover with Simple totals turned on for a stacked layer Omni hides labels that overlap, and labels on bars often overlap. If labels are missing, turn on **Show all** in the layer's label options. ## Tooltips On line, area, and scatter layers, the tooltip displays when you hover near a point, and the point is highlighted. ## Axis sort order For a text field on the X-axis: * **Automatic** keeps the order of the query results when the query is sorted. * **Ascending** sorts alphabetically. * **Descending** sorts in reverse alphabetical order. ## Limitations * Separate layers don't stack on each other. Use [Measure values](/visualize-present/visualizations/layers/measure-names-values) to stack measures. * Each color field has one set of colors for the whole chart. You can't color the same field differently in two layers. * Layers on one axis share the axis's scale and title. * Two layers that each leave out a different dimension can't both get totals. One of them looks jagged. Refer to [Smart aggregation](/visualize-present/visualizations/layers/smart-aggregation#what-to-expect). * **Size** is available only on **Scatter** layers. If you change a scatter layer to another mark, its size setting is removed. ## Next steps * [Measure names and Measure values](/visualize-present/visualizations/layers/measure-names-values) * [Smart aggregation](/visualize-present/visualizations/layers/smart-aggregation) * [Switch between the layers and classic editors](/visualize-present/visualizations/layers/switch-editors) * [Build visualizations with AI](/ai/visualizations)