Merge numerous photos into a single large image.
Basic coloring can be done by setting two attributes on the node: fill and stroke. fill sets the color inside the object and stroke sets the color of the line drawn around the object
<rect
x="10"
y="10"
width="100"
height="100"
stroke="blue"
fill="purple"
fill-opacity="0.5"
stroke-opacity="0.8" />