Marker symbol layers are components of symbols that draw a specific shape—such as a circle, a tree, or a three-dimensional lamppost—at a specific location relative to geometry. They are most often used in point symbols, but they can also be included in line symbols and polygon symbols to draw shapes along lines and outlines or within areas. Marker symbol layers in line or polygon symbols include marker placements to define how the markers are positioned relative to the geometry. A marker symbol layer can be one of three types. Set the type in the Format Symbol mode of the Symbology pane, on the Properties tab, on the Layers tab .
Uses vector geometry to define the shape of the marker.
Uses an image to define the appearance of the marker.
3D model marker
Uses a 3D model to define the appearance of the marker. When used in a 2D context, a flat thumbnail image of the model is drawn.
Uses a rule package to define a 3D object as the marker. Procedural markers are only relevant in a 3D context. Procedural content is ignored and does not draw when the symbol is used in a 2D context, such as a map.
Shape marker symbol layers
Shape marker layers use vector graphic geometry to define the shape and appearance of the marker. This geometry is derived from one of four sources described in the following table:
Insert shape from Form
Choose from a small gallery of simple, common shapes.
Insert shape from Style
Choose an existing point symbol in a style to use as a source for the marker shape. Multilayer point symbols result in a complex marker layer that is composed of multiple symbol elements. Click the Element gallery to view the elements, and select an element to modify its appearance. Here, each element is drawn with a separate symbol, instead of one symbol applied to the whole marker layer.
Insert shape from Font
Choose a glyph from an installed font as the geometry source for the shape of the marker layer.
Insert shape from File
Choose a scalable vector graphics file (.svg) or an enhanced metafile (.emf).
When marker geometry is imported from a scalable vector graphics file (.svg), only a subset of the SVG functionality is supported. SVG files with simple paths, shapes, text, inline paint attributes, clipping paths, and images are supported. Transparent graphics in SVG files are converted to images when you import. For them to remain as vector elements, make the transparent elements fully opaque in the SVG file (using an external drawing application) before import. Then, reapply a transparent color to the element after import. See Scalable vector graphics support to learn more.
Regardless of how the marker shape geometry is derived, the shape itself is drawn using a polygon symbol, as defined by the Shape fill symbol pull-down gallery. Choose a symbol from this gallery or click More polygon symbols in the gallery to choose one from available styles. Only the basic properties of the polygon symbol—Color, Outline color, and Outline width—can be modified.
When sizing shape marker symbol layers, you can use Respect frame to ensure uniform sizing of related symbol layers. The frame is generally larger than the visible part of the symbol graphic. The default setting for newly created shape symbol markers is to respect the frame. When symbols are converted from old projects or styles, this property is set to match their previous appearance.
In a 3D context, you can specify a Depth for shape marker layers to give them a sense of thickness. Check the Stand vertically check box to stand the symbol upright, as if it is locked in place. You can navigate above and behind it when it is in this state.
When a marker layer contains symbol elements, you can edit the symbol properties of each element. You can modify some basic properties of the element directly below the Element gallery. To access additional symbol properties of the element, follow these steps:
- Choose the element from the Element gallery.
- Open the symbol gallery for the element. Depending on the graphic geometry of the current element, this gallery is named Shape point symbol, Shape line symbol, Shape polygon symbol, or Shape text symbol.
- Click Format point symbol, Format line symbol, Format polygon symbol, or Format text symbol in the gallery menu, whichever is shown.
- In the Format Embedded Symbol subpane, modify the symbol as necessary.
- To save the custom embedded symbol for reuse, click the menu button in the upper right corner and click Save embedded symbol to style.
- Click Return to previous symbology page to return to the Format Symbol pane.
Picture marker symbol layers
Picture marker symbol layers use an image file to define the marker instead of a vector shape. This image is derived from either an existing point symbol or an image file. In the Format Symbol mode of the Symbology pane, on the Properties tab, on the Layers tab , expand the Appearance group. Click Picture to browse to an image file. Adjust the Quality, Tint, and Size properties as necessary.
Insert picture from Style
Choose from an existing point symbol in a style.
Insert picture from File
Choose a bitmap (.bmp), JPEG (.jpg), PNG (.png), or GIF (.gif) file.
To vary the image of a picture marker symbol layer with attribute-driven symbology, the images must be stored in either a raster or a BLOB field. Consider storing these in an attachments table, joining the table to the feature class, and specifying the attachment field for the symbology.
Also in the Appearance group, adjust the Quality, Tint, and Size properties of the marker symbol layer as necessary. In a 3D context, you can check Invert backface image to show the image right-reading when viewed from behind. You can specify a Depth for picture marker layers to give them a sense of thickness. Check Stand vertically to stand the symbol upright, as though it is locked in place. You can navigate above and behind it when it is in this state.
Set the Tint property to white, the default setting, to draw the image in its native colors. Setting this property to no color causes no image to be drawn.
3D model marker symbol layers
3D model marker symbol layers use a true three-dimensional graphical model to define the marker. This model is derived either from a gallery of simple volumes, from a model in an existing 3D point symbol, or from a file. In the Format Symbol mode of the Symbology pane, on the Properties tab, on the Layers tab , expand the Appearance group.
Insert model from Form
Choose from a small gallery of simple, common volumes.
Insert model from Style
Choose from an existing point symbol in a style.
Insert model from File
Choose a COLLADA (.dae), 3ds Max (.3ds), OpenFlight (.flt), Wavefront (.obj), GL Transmission Format (.glTF), or a Binary GL Transmission Format (.glb) file.
See glTF markers for a discussion of the .glTF and .glb formats, and a detailed list of supported features from that specification.
Also in the Appearance group, adjust the Height (Z), Width (X), and Depth (Y) properties of the marker symbol layer as necessary. Click the bar to the left of these properties to change whether they are linked together to adjust relatively. The Dominant size axis property dictates which size is affected by global size changes made to the point symbol at the basic properties level.
Tint 3D model marker layers
To add color to 3D model markers, you must check the Tint model check box to activate the color picker. By default, white is applied, but you can choose a different color. The color can be applied to the entire model or only to specific faces, depending on how the underlying 3D model was authored. Models that appear solid white natively are typically meant for thematic applications and are completely colored when a tint is applied.
When Tint model is unchecked, there is no color applied to the model and it draws in its native colors. Note that this is different than applying white or fully transparent tinting, which could yield different results. When Tint model is unchecked, the color picker is disabled, and the symbol layer is color locked and disabled . This means that changes in color to the symbol as a whole, either from the Symbol tab or from the layer symbology, will not affect the color of this 3D model marker symbol layer.
Procedural marker symbol layers
Procedural markers rely on a rule package to define a 3D object as the marker. Rule packages are scripts that define the appearance of these objects and expose some properties for configuration. Rule packages are created in ArcGIS CityEngine. The @StartRule of the rule package must specify @InPoint annotation to indicate that it is intended for point geometry. The properties that you see for a procedural marker symbol layer are defined by the rule package itself. There are default values for each of these properties, but you can override them with explicit values or by connecting the properties to data attributes.
Marker symbol layer properties
In addition to the visual shape of the marker layer, there are more properties that dictate how the marker is sized and positioned with respect to feature geometry, and how it behaves as it is rotated. There is an order of operations to how these categories of symbol properties are applied. It's important to take this into account when you build complex marker layers that include rotation and offsets. The order generally follows the order that the properties are presented in the Format Symbol pane:
- Stand vertically (3D property only)—The orientation of the marker relative to the directional axes.
- Anchor point—The position of the marker relative to feature geometry.
- Rotation—The marker is rotated around the anchor points.
- Size—The marker is sized from the anchor point if it is set to a relative position (or if it is sized from the basic symbol properties).
- Offsets—The marker is translated away from the feature geometry with all other transformations intact.