This digital painting is pretty old, as the date in the title suggests.  I included it here so you could compare it to my more current work.  Ha-ha.  Maybe it hasn't changed all that much.
 
This has lots of spiked tree shapes which contrast with the massive blocks of the limestone cliffs, exposed by the erosive power of South Piney Creek which is now fed by several reservoirs in the Bighorn Mountains of Wyoming.  Imagine back in time how spring runoff might have been huge to have eroded away hundreds of feet of solid rock.
 
The use of texture, admittedly overdone, suggests the brick-like solidity of the rock, and the more patterned textures in the trees mimic the more random directions of the pine needles in the Ponderosa pine forest.  Changing textures also help differentiate the shapes, even though they have the same color.
 
The color groups create planes in the picture from foreground to background, and reinforce the geometrical nature of the composition.  This might be appropriate for a semi-abstract painting, which exists in a two-dimensional format.  Imagine living in Flat Land, where the third dimension doesn't exist, except for overlays of two-dimensional planes.
 
The linear outlines of constant thickness provide uniformity throughout the composition, and offer value contrast with their associated group color.  They also help define the shapes within the group, without destroying the unity of the overall groupings of shapes.  These outlines disappear at the sky line, which perhaps suggests the intimate contact of the atmosphere with all living and non-living objects on the Earth's surface.