it successfully to create crop fields and place trees around a
farmstead on the prairie.
Terragen has a specialized shader to simulate water.
Adjustments are available to affect surface waves, color reflec-
tivity, and other adjustments to create a glassy lake, a river or
even an ocean surface. The most important adjustment on a
water layer is the level which will bring it into your scene, and
keep it confined to a lake or river bed.
Fractal shader layers do a pretty good job of simulating dis-
tant grass and bushes, but eventually your scene will need
more detailed objects such as trees, weeds, and grass nearer
the camera. Inclusion of externally modeled plants and trees
is supported by Terragen. Commercial and free plant models
can be added to your scene with population nodes that can
create a field of weeds or entire forests. The placement of
objects is controlled by distribution settings in the population
node, which randomly places replicated objects into an area,
rotating and varying the size of a basic object model. [9] This
variation can take a single tree model and create a convincing
forest from that one model. Using the painted shader as a filter
(“blended shader” in Terragen terms) can provide fairly precise
control over where objects are placed. In [2], tree placement
along the Missouri river as well as the crop fields were con-
trolled with a painted shader applied to the tree population.
Computer-generated backdrops - 8
9. Several examples of rendered plant models from
Xfrog and Mr Lampost. Using populations of object
models, entire forests can be created.
10. This is a screen capture of PTGui at it stitches the
14 images that made up my Carter, MT panoramic view.
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MRH-Jul 2014
