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Guest tml1024

PKX polygons or agn polygon regions?

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Which is the best way, from FSX performance perspective, to add true-to-reality shaped forest areas, parks, grass fields, parking lots, container yards etc?As PKX polygons in a shp2vec produced bgl file? Or as polygon regions in an agn file?I think I have a pretty good understanding of the shp2vec style vector terrain (and I have written some software to mangle a certain source of road, water etc data into form for FSX's shp2vec, and it works as expected and I am happy). The autogen (annotator) stuff is more of a mystery to me...To use the agn stuff, does that always require one has corresponding aerial/satellite imagery that will then cover landclass-based generic terrain imagery and vector roads, water etc? (Except freeway traffic, it seems, for some reason?)Please note that I am specifically not asking which approach has the easiest-to-use SDK or 3rd party tool to make it... although I admit that Autogen Annotator is pretty low on the usability scale, and also the documentation of that aspect is IMHO much less clear than that for the vector terrain stuff. Is it possible to generate .agn files programmatically, has that format been reverse engineered?--tml

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Let's see. There are basically 2 different types of ground scenery: - vector terrain where the different elements are defined by simple polygons with default textures; - custom ground made from aerial images.The vector terrain uses land class values to determine the ground textures that are displayed. These default ground textures have all seasonal and night variations, and are populated with autogen.On the other hand, the custom ground will always cover the vector terrain elements, but you will have to make the seasonal and night variants yourself, and also add the autogen annotations by hand.The Autogen Annotator is not difficult to use, although the process can be extremely tedious. For a simple illustrated explanation, please see Using the Autogen Annotatorhttp://library.avsim.net/esearch.php?&DLID=107335This tool is used to add autogen to custom ground, but it can also be used to modify the autogen annotations of default ground textures.So, back to your question; how to best represent forest areas, with PKX polygons or with custom ground?It all depends on you, the quality of your sources, and how you balance the benefits and inconveniences of each.You can draw a PKX quite easily and it will be very compact in size, contain all seasonal and night variants, have autogen, and load quickly with little if any performance penalty.On the other hand, custom ground is the real thing, but you won't have seasons unless you are an excellent graphics artist, and adding autogen is a long and boring process.When you distinguish between PKX and polygon region annotations, you make a very subtle distinction. It is hard to know which has better performance, as I don't believe that anybody has tested that aspect of the game. Perhaps the developers could answer that question.The autogen format was documented in this forum, but for FS 9. You should search the forum for more information.Also, custom ground will always cover vector elements, but any objects that are attached to the vectors will display. This is quite handy, as it means that we do not lose electrical pylons and that we can easily depict moving traffic on the custom ground.Best regards.Luis

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>The autogen format was documented in this forum, but for FS 9.Yeah, I found this thread: http://forums.avsim.net/dcboard.php?az=sho...1&mesg_id=15471 But in FSX the native agn format has changed. The new files seem to start with "RIFF" which I guess should be considered a good sign, it is based on the well-documented generic RIFF format http://en.wikipedia.org/wiki/RIFF . Or actually, the format of actual data chunks are still of course undocumented (but presumably similar in spirit to the FS2002/FS2004 stuff).Thanks,--tml

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