Filter: add a drop shadow to an element

With the filter_drop_shadow() drop shadow appears beneath the input image or shape and its offset is controlled by dx and dy. The blurring of the drop shadow is set by the stdev value.

filter_drop_shadow(dx = 0.2, dy = 0.2, stdev = 1, color = "black", opacity = 1)

Arguments

dx, dy	The offset of the drop shadow compared to the position of the input image or shape.
stdev	The number of standard deviations for the blur effect.
color	The color of the drop shadow.
opacity	The opacity of the drop shadow. We can use a real number from 0 to 1 or a value in percentage units.

Examples

# Apply a drop shadow filter on a
# text element (orange in color,
# and semi-opaque)
SVG(width = 250, height = 100) %>%
  svg_filter(
    id = "shadow",
    filters = list(
      filter_drop_shadow(
        dx = 1, dy = 2,
        color = "orange",
        opacity = 0.5
      )
    )
  ) %>%
  svg_text(
    x = 10, y = 40,
    text = "Shadowed",
    attrs = svg_attrs_pres(
      font_size = "2em",
      fill = "#555555",
      font_weight = "bolder",
      filter = "shadow"
    )
  )
#> <svg width="250" height="100">
#>   <defs>
#>     <filter id="shadow" width="250" height="100">
#>       <feDropShadow dx="1" dy="2" stdDeviation="1" flood-color="orange" flood-opacity="0.5"/>
#>     </filter>
#>   </defs>
#>   <text x="10" y="40" fill="#555555" font-size="2em" font-weight="bolder" filter="url(#shadow)">Shadowed</text>
#> </svg>