This text was supplied by Michel Verheughe

"Unofficial" texts are member contributions that have not yet been discussed or approved by the ESP community.

X-Plane default textures

When Austin Meyer made the "world," he took some digital elevation data, then ran a program that defines every polygon near 0 Ft elevation to be water.

To the land and to the water, he sat a texture. Then he made coastal transition and mountain textures that are placed " on the fly," i.e. they are calculated and placed at the moment of displaying in X-Plane. The mountain texture is placed when the slope
of a polygon exceed a certain limit. In addition he has added snow texture when the temperature is sub-zero and "Caribbean water" at a equatorial latitudes.

This was very clever because, at little cost, he was able to provide a worldwide scenery without editing the actual scenery (ENV) files. But the resolution is coarse and places like The Netherlands were under water while the Norwegian fjords were
landlocked and silted with sandy transitions.

By providing WorldMaker, Austin allowed us to modify these scenery files and make them more accurate. Then he invited us to upload our work on his site so that he could update his "world" and distribute it again with the next release of his X-Plane CD.
This was excellent ... until the custom textures appeared with X-Plane 4.7.

The problems are as follow:
  • - The "on the fly" mountain texturing is not working as it should and the results are sometimes unexpected.

  • - The "on the fly" technique requires real-time calculation that could be used to something else.

  • - All these textures are loaded in memory and the "on the fly" calculation is done, even if every polygon in the file(s) is covered with a custom texture.

  • - When a file has custom textures and it is then uploaded to the, the texture is not following. Then, for a user that download this file from the site (or the CD), these textured polygons will appear white because - while the texture is not there its name is still imbedded in the scenery file.

Our believe is that it is time to change this and produce quality scenery where custom textures and custom objects are following. Of course, that can't be done on the, and be distributed on the X-Plane CD. Thad Parker pioneered the idea to
have an independent site where complete scenery packages could be linked from the designers' websites.

But these designers want full control over the scenery and no more "on the fly" calculations. However a default texture has still to be placed there where there is nothing, and that is: un-worked land area and the vast oceans. Our plan is then to ask
Austin to forget the "on the fly" calculations and keep only wat.bmp and grs.bmp as default textures. Of course if he does this, Austin will make his "default" scenery less attractive. This is why we have to make a lot of scenery with our standard, so
that Austin realized that these "independent" scenery are a greater gain to his product, than the default scenery.

In the meantime, we have decided to make our scenery as if there was only wat.bmp and grs.bmp as default textures. To do so, we go in the default textures folder, copy wat.bmp to all water transitions, and grs.bmp to all land transition textures.

Since the ESP texture definitions has a one called "xp_coast_wat.bmp" and that it is supposed to cover the first coastal water polygon, we can represent the same sandy coastline as the default transition. But in places where land falls steep into the sea
- like in the Norwegian fjords - then we will not used this texture at all. If we are working e.g. on Iceland, Jan Mayen or the Spitsberg islands (still in Europe), then is even possible to make this coastal transition as drift ice.