Height Map Displacement Shading

The textured forest looks pretty bad when it does not have shading-  It is pretty much impossible to distinguish different trees other than on horizons-

Textured Forest, no shading

Luckily implementing dynamic shading is not too difficult, and a variety of shading techniques can be combined to create a convincing effect.

Terrain Shading

Terrain Shading – trees will be shaded in shadow of terrain contours

lighting factor writen to Forest Map – passed through Displacement Filter

Height Shading

Height Shading – Assuming trees are shaded more on the bottom -

                                    Forest Height is determined by texture height * forest Value in terrain Vertices

                                    Forest Value passed through Forest Map –

                        bottomShading = finalHeight/ForestValue  (Relative Max Height)

Emboss Bump Map Shading

Embos Bump Mapping – Technique used to approximate bump mapping – may still show up in terrain shadows-

Combined Shading

Combined Shading – Shading methods multiplied together- some artifacts from embos bump map.. 

 

These shading methods require 2 more channels to be passed through the initial mapping process- Relative height for height shading and a light factor calculated for the emboss and terrain shading