1. Changed airport_grass_overlay.png to airport_grass_structure_overlay2.png
- africa_rainforest.xml, azores.xml, brazil_amazon_forest.xml, brazil_pampas.xml, brazil.pantanal.xml, california.xml, corse.xml, global-summer.xml, mexico.xml, south_east_asia.xml, southern_europe.xml, tropical_south_america.xml, us_southwest.xml
2. Added old airport_grass_overlay.png as airport_grass_structure_overlay1.png
- jan-mayen.xml, ascension.xml (volcanic island)
3. Changed <overlay_layer_magnification> for files using airport_grass_structure_overlay2.png. Conversion: 8.0 units in structure_overlay1 = 60.0 units in structure_overlay2.
- 60.0: africa_rainforest.xml, azores.xml, brazil_amazon_forest.xml, brazil_pampas.xml (4.0), brazil.pantanal.xml, california.xml (grain_layer), corse.xml (grain_layer), global-summer.xml, jan_mayen.xml, mexico.xml (grain_layer 4.0), south_east_asia.xml, southern_europe.xml (grain_layer 4.0), tropical_south_america.xml (grain_layer), us_southwest.xml (grain_layer)
4. Specified <overlay_layer_magnification> for AirportKeep using a normal texture in the n="14" slot instead of a structure texture without specifying magnification. The reason is the new default structure texture uses a much higher magnification. The old value used was 8.0 from global-summer.xml.
- us_southwest.xml (8.0), california.xml (8.0),
5. Specify <grain_layer_magnification> as 4.0 for jan-mayen.xml. Global-summer.xml didn't specify it so the material got settings from the effect default.
6. Multiply alpha channel of airport_grass_structure_overlay2.png by 0.7 to reduce very subtle tiling to almost zero for worst case (e.g. white areas of southern_europe.xml keep). This is visible only at closer ranges at very specific angles. Change southern_europe.xml grain_layer_magnification to 50.0. Best fixed with grain_alpha uniform.a new
7. Increase <overlay_alpha> to greater than 1.0 in global_summer.xml for structure overlays for keeps to compensate for multiplying strucuture_overlay2.png alpha by 0.7. Target goal was 0.85 - there is some almost imperceptible tiling from very specific angle close up and this can be lowered a bit further if needed.
8. Specify <overlay_alpha> as 1.0 for overlays where airport_grass_structure_overlay2.png is not used, or is used in the n="15" grain layer slot.
- africa_desert.xml, africa_mediteranean.xml, ascension.xml, brazil-caatinga.xml, corse.xml, california.xml, greenland.xml (new definition), hawaii.xml, iceland.xml (new definition), southern_europe.xml, tropical_south_america.xml
9. Changed name of airport-grass-autumn.png to airport-grass-summer2.png.
10. Use airport-grass-summer2.png (brown-grey-green) grass texture for in greenland.xml as the green one is out of place. D-ECHO is working further on Northern area keep.
11. Changed <texture> reference in california.xml from airport-grass-autumn.png to airport-grass-summer.png.
12 Grass scale for airport-grass-structureoverlay2.png: roughly 60 (roughly guessed by displaying RBG strucuture texture against airport_grass2.png.).
13. Changed california-grass.png to california-grass2.png:
mexico.xml,
14. Added 3d grass to california and iceland grass definitions.
15. Iceland and BIKF for the moment uses the dull brown-grey.green airport-grass-summer2.png. Once a control for specifying grass texture magnification is in it's possible to do a dark volcanic underlying texture with spots of grass/moss.
16. Started a Keep definition in europe.xml so maybe in future a new global grass type can be a bit less yellow than for Europe and mid latitude locations away from the equator.
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Note:
Possible unresolved minor problem found with colour of 3d grass: AirportKeep effects can specify textures with grass colours in either the base slot or the overlay slot. e.g. us-southwest.xml specifies the grass colour in the overlay slot and the ground underneath in the base layer slot.
The 3d grass shader assumes a magnification of 1.0. When overlay or base layer magnifications are not 1.0 same the grass colours don't quite line up. Some difference between ground underneath and grass is probably desired to make the grass blades more obvious. It's not a big problem in dryer areas as the grass density is low and the dry textures colours are similar looking. Eventual fix: add a <grass_color_layer_magnification>.
