Symbols in visual art are like those found in literature and music and also mathematics.
Using an analogy from music think about how Leitmotifs can provide meaning in music. for an example of this think of the themes in Star Wars - click here for a Wikipedia article.
Notice the paintng by Pierre Bonnard - he is using pretty much all primary colors to create an image of very bright light. This is called impressionist color. The idea is to create an illusion of more light.
notice how this is different than using tints and shades - adding black and white - this is by Pieter Claesz 1628
Here is what one artist has to say about Dreamtime painting..
Dreamtime or Creation Time is the period when Baayama (God) and his ancestral
Spirit Deity created and helps to shape the world we know today.
Dreamtime Stories are unique to an individual area describing the creation of
the land its geographic conjures and waterways. These stories also tell of the
creation of all living creatures.
Deep within these stories are held the ancient “Lore” of our culture.
Our morals, respect and beliefs all stem from our understanding of where and
how we fit into the creation process. These stories guided and protects our
people giving them identity and strength.
Here are some examples -
Still from Sleeping Beauty - Landscape design by Evyind Earle
Concept design for Sleeping Beauty - signed by Evyind Earle
characters put into a cell. Note the detail on the trees.
Concept sketch from Avatar - even more recent illustrators use the same techniques of layers with details on top.
link to Wikipedia article on Jan Vermeer Dutch painter 1632-1675. Known for masterful depiction of light.