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Advanced enhancements

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The forest borders (see 3.2 – Apply the changes)

For better flattening of the forest texture where it might disappear, I did the brightness/contrast adjusment using an adjustment layer with a mask. Create this mask with the Project.tga converted to grayscale, invert it, lighten it a lot with levels, with a high gamma (most parts of the mask must be near white). Then, tune Brightness and Contrast through this mask. This allows to erase the textures details more efficiently.

Selective forest shadows (see 3.3)

I handle the forest with two different displacement maps, whether it’s conifer forest or evergreen/mixed. The shadows are sharper for conifers. (But I should once travel to the U.S just to see if these are some fir and not some round head pine trees!)
Just use some different colour when you design the “textures for selection” (1.1).

Varying shadow lengths (see 3.3)

I wanted trees to cast different shadow’s lengths depending on the sun’s angle with the terrain. We have this information with the shadow map! The deeper the terrain shadow, the smaller the angle, and the longer are the shadows cast by the trees (or any object).

With the help of SELECTION > COLOR RANGE, create three channels with the selections including shades from black to a decreasing level of lightness. Remove the black areas in each. The pictures show the three channels (red) used as masks over the selected areas (for of better understanding purpose).


During the shadowing process :
  1. Apply only once the displacement map on the forest.
  2. Use the first channel to select a limited forest area, copy it to a new layer and apply two DISPLACE filters.
  3. Go on with the other channels, each time applying more successive DISPLACE filters.

This effect adds a lot to the picture’s realism. See the result on the final sample below, especially the lower left corner.

Selective buildings shadows (see 3.4)

Larger buildings cast longer shadow. I draw suburban and commercial textures for selection with different colors, and handled them separately with the help of the selection map. For an even better effect, you may use a special color for all the large buildings on each sel texture (thus using three colors on each texture) and thereafter let them cast really long shadows (i.e. apply a lot of displace filters).

Automation in Photoshop

The whole process explained in this document is quite time consuming, and when it comes to create vast landscapes as wide as full globe tiles, it would be a real pain if we couldn’t do some macros to automate those repetitive tasks. It was a main objective in the development; therefore all the steps can be programmed as Photoshop “actions”. Read the software’s help for good understanding and use of actions. The following aspects need some attention when using actions :

  •  Don’t select the colours with the magic wand tool, rather use SELECTION > COLOR RANGE.
  •  Don’t drag the layers from one document to another. Use COPY / PASTE.
  •  Possibly some problems may appear if the result of a selection is empty. I’ll give a look at this issue.

After enhancements - a close look :