> For the complete documentation index, see [llms.txt](https://docs.carto.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.carto.com/carto-user-manual/maps/layers.md). # Layers Layers in Builder are connected to data sources and are used to render features on a map by directly connecting to your data warehouse. Once a data source is added to Builder, a layer is automatically added for that data source. If the spatial definition is valid, the features will be rendered on the map. Learn more about defining source spatial data in this [section](/carto-user-manual/maps/data-sources/defining-source-spatial-data.md). ## Layer options When working with layers in Builder, you have the following options: * **Zoom to:** Zoom to the layer extent, taking into account any filtering applied in Widgets and/or Parameters when applicable. * **Show only this/Show all layers:** Easily set layers visibility on and off. * **Layer style:** Access the layer panel to set your layer styling configuration. * **Duplicate layer**: Duplicate a layer with the same styling properties. * **Rename:** Edit the name of your layer. * **Delete**: Remove the layer and its corresponding source. ## Layer groups When a map has many layers, you can organize them into named, collapsible **groups**. Groups appear in both places your layers show up, the **layer panel** while you build and the **legend** your viewers see, so the same structure keeps a busy map readable on both sides. Grouping is an organizational tool, so it never changes your data or how individual features are styled.
### Creating and managing groups From the layer panel you can: * **Create group:** Open the add menu in the layer panel and choose **Create group** to add a new group. New groups get a default name that you can edit at any time. * **Add to group / Move to group:** From a layer's options menu, choose **Add to group** to place it in an existing group, or drag the layer onto the group. Use **Move to group** to send a grouped layer to a different group. * **Remove from group:** Return a layer to the top level of the layer list. * **Rename:** Click the group name to edit it. * **Expand / Collapse:** Fold a group to tuck its layers away in the panel, or expand it to see them again. This only changes the panel, not the map. * **Delete group:** Remove the group. Its layers return to the top level of the list. Deleting a group never deletes your layers or data. You can also reorder layers and groups by dragging them within the panel. The order in the panel sets the drawing order on the map, with layers at the top drawn above the ones below. ### Group visibility Each group has its own visibility control: * **Hide group / Show group:** Turn every layer in the group off or on at once. A group's visibility combines with each layer's own visibility, so a layer is drawn on the map only when both the group and the layer are set to visible. * **Show only this:** Show the layers in this group and hide everything else, so you can focus on one part of the map. * **Zoom to:** Frame the map around the layers in the group. In the [legend](/carto-user-manual/maps/legend.md), groups appear as labelled sections that mirror the layer panel, so the people you share the map with get the same organized view rather than a flat list. ## Visualization types The spatial definition of the source linked to a layer specifies the layer visualization type and additional visualization and styling options. The different layer visualization types supported in Buider are: * [**Point**](/carto-user-manual/maps/layers/point.md): Displays as point geometries. Point data can be dynamically aggregated to the following types: * [**Grid**](/carto-user-manual/maps/layers/point/grid-point-aggregation.md)**:** Aggregated point geometry to grid. * [**H3**](/carto-user-manual/maps/layers/point/h3-point-aggregation.md): Aggregated point geometry to hexagonal cells. * [**Heatmap**](/carto-user-manual/maps/layers/point/heatmap-point-aggregation.md): Aggregated point geometry by density. * [**Cluster**](/carto-user-manual/maps/layers/point/cluster-point-aggregation.md)**:** Aggregated point geometry by circles. * [**Polygon**](/carto-user-manual/maps/layers/polygon.md): Displays as polygon geometries. * [**Line**](/carto-user-manual/maps/layers/line.md): Displays as line geometries. * [**Grid**](/carto-user-manual/maps/layers/grid.md)**:** Displays features as grid cells. * [**H3**](/carto-user-manual/maps/layers/h3.md): Displays features as hexagon cells. * [**Raster**](/carto-user-manual/maps/layers/raster.md): Displays a grid of pixels. ### Visibility by zoom level Control the zoom range where a layer should be visibile. This is useful for combining different type of sources, such as aggregated data for lower zoom levels and non-aggregated data for higher levels or visualizing different administrative levels.
### Aggregate by geometry If you are working with point, polygon or line layer visualization types containing identical geometries with varying attributes (e.g., weather stations or buildings), you can use the **Aggregate by geometry** functionality to aggregate your layer based on a distinct spatial column. This allows you to: * Aggregate geometries in your layer ensuring an optimal performance. * Aggregate styling and interaction attributes to retrieve relevant information link to your aggregated feature. * Maintain widgets functionality over the original source, enabling drill-down operations for deeper insights. For derived metrics like rates, ratios and weighted averages, **Aggregate by geometry** also supports [custom SQL aggregation expressions](/carto-user-manual/maps/layers/point.md#custom-aggregation-expressions) on styling channels and popup fields. Available on [point](/carto-user-manual/maps/layers/point.md#custom-aggregation-expressions), [line](/carto-user-manual/maps/layers/line.md#custom-aggregation-expressions) and [polygon](/carto-user-manual/maps/layers/polygon.md#custom-aggregation-expressions) layers.
## Layer styling Layer styling is essential for making your maps informative and engaging. Below are generic aspects of visualization and styling options available in Builder. For more detailed styling capabilities for a specific layer type, we recommend to check each layer type as defined above. ### Labels Text labels add typographic detail to your map, helping you communicate feature names or values directly on the Map View. Labels are available for **point, polygon, and line** layers. Enable the **Labels** option in the layer panel, choose the column to display, and adjust **Font Size**, **Font Color**, **Text Anchor**, and **Placement**. CARTO places each label automatically, at the center of every polygon and along the middle of every line. For **line** layers you can also set a **unique ID field**. A line feature is often split across several map tiles, which would otherwise produce one label per tile. Choosing a column that identifies each feature, such as a road name or ID, keeps a single label per feature. ### Color palettes When styling layers in Builder, you can choose a few different types of **color palettes**: * **Diverging:** Highlight values that are above and below an interesting mid-point in quantitative data. This is a great way to show data values that differ greatly from the norm. For example, you may use a diverging colour scheme to show population change. * **Sequential:** Ideal for data that follows an order, often numeric ranging from low to high. For example, you may use a sequential colour scheme to show counts within a H3 grid. * **Qualitative:** Represents different categories of data. For example, a qualitative scheme is a good choice for showing different types of Points of Interest. * **Singlehue:** Gradual transition of a single color from light to dark. For example to visualize the quality network coverage signal. * **Custom:** Pick a new color either by clicking on the color picker or inputting HEX/RGB values. Color steps can be added, removed and shuffled. {% hint style="info" %} When working with [**aggregated data sources**](/carto-user-manual/maps/data-sources.md#aggregated-grids), you will need to select an aggregation operation for your columns. Connections to **Redshift** clusters only support aggregation of categorical properties by any value. {% endhint %} Admins can also create **custom color palettes** from the organization settings. These are reusable color schemes and they are available to the whole organization, removing the need to define a new custom palette every time a custom set of colours is used for styling. For more information, see our [article on custom color palettes](/carto-user-manual/settings/customizations/configuring-custom-color-palettes.md). ### Color schema by HexColor You can also tap into the **HexColor** feature to style qualitative data using the hex color codes from either your table or SQL query source. To harness this capability: 1. Navigate to the *Color based on* selector and choose the text column you want to associate with the hex color code. 2. In the *Palette* section, select the 'HexColor' option. 3. Finally, choose the column containing the hex color code values. For more information about how to leverage this functionality see this [tutorial](https://academy.carto.com/building-interactive-maps/data-visualization/style-qualitative-data-using-hex-color-codes). {% hint style="warning" %} **Pre-generated tileset** layers styled with HexColor are not currently supported in the legend. If you require this functionality, please provide feedback through your CARTO point of contact. {% endhint %} ### Color Scale Depending on the property selected to define your color schema, you have different color scale functionalities to define the color classification method. For numeric columns, you can choose the following data classification methods: * **Quantile**: A quantile color scale is determined by rank. A quantile classification is well suited to linearly distributed data. Each quantile class contains an equal number of features. There are no empty classes or classes with too few or too many values. This can be misleading sometimes, since similar features can be placed in adjacent classes or widely different values can be in the same class, due to equal number grouping. * **Quantize**: A quantized color scale is determined by grouping values in discrete increments. It allows to transform an initially continuous range into a discrete set of classes. Quantize scales will slice the domain’s extent into intervals of roughly equal lengths. * **Logarithmic**: A Logarithmic scale based on powers of `10` will be created automatically, based on the number of steps in the selected color palette. Logarithmic scales tend to work well with [aggregated data sources](/carto-user-manual/maps/data-sources.md#aggregated-grids). * **Custom**: A custom color scale is determined by arbitrary breaks in the classification. A custom scale is well suited to tweak color ramps, adjusting the values to fine tune the visualizations. For text columns, you can use the **Ordinal** classification method to set a specific category to each color value:
### 3D visualization using Height Builders allows you to assign heights to build 3D visualization for both polygons and spatial index sources. You can activate this option in the Height section, using the slider to define a fix value or using a property to define the height.
When using the Height functionality, remember to activate the 3D view located in the toolbar above the map. Using this, you can achieve stunning visualizations as per below map. {% embed url="" %} Explore a map with 3D polygons whose height is defined by the number of floors. {% endembed %} ## Layer blending Layer blending is a technique used to determine how overlapping features in different layers interact in terms of their visual representation. When two layers are blended, you can select the following blending options: * **Additive:** This mode adds the color values of overlapping features. When two colors are added together, the resulting color is often lighter. This blending mode is commonly used to visualize densities or intensities. * **Subtractive:** This blending mode subtracts the color values of the upper layer from the layer beneath it. The result is typically a darker color. In some contexts, this mode can help emphasize differences between layers. --- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com. ## Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter: ``` GET https://docs.carto.com/carto-user-manual/maps/layers.md?ask=&goal= ``` `ask` is the immediate question: it should be specific, self-contained, and written in natural language. `goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.