Tech Support Blog

  • Subscribe to our RSS feed.
  • Twitter
  • StumbleUpon
  • Reddit
  • Facebook
  • Digg

Friday, 9 April 2010

What an Evil Disaster

Posted on 16:45 by Unknown
After about a week of on and off hacking, I have finally knocked down one of the major stumbling blocks to getting WED 1.1 up to beta quality: exporting UV-mapped (texture mapped) bezier polygons that cross DSF borders. It works! Well, sort of.

If you have tried to program polygon cutting algorithms, you can appreciate the difficulty of an algorithm that:
  • Clips polygons robustly (including holes and other weird topology) and
  • Maintains a UV mapping while doing this and
  • Works with bezier curves and not just line segments.
WED now does all three! This was the ugliest and hardest part of the DSF exporter, and a big missing piece from going beta.

Of course, there is one problem: X-Plane can't read the bezier curves.

The problem is a simple defect in how X-Plane manages DSFs.
  • A valid bezier polygon, fully inside the DSF tile, may have control handles that go outside the tile.
  • X-Plane can't handle any DSF coordinates outside the tile.
Doh!

I am not sure what I will do about this, but in the short term, I fear X-Plane will remain limited. Probably the best short term option is to have WED at least flag such problematic bezier polygons; it is possible to approximate them or edit them to make the export work.

There is still a little bit more exporter code to write, including the line segment exporter (which is separate from the polygon exporter), but with luck the whole DSF export path should be cleaned up in the next few days.
Email ThisBlogThis!Share to XShare to FacebookShare to Pinterest
Posted in file formats, scenery system, tools | No comments
Newer Post Older Post Home

0 comments:

Post a Comment

Subscribe to: Post Comments (Atom)

Popular Posts

  • Developer Hardware
    So...just how awesome is my main development machine? Not that awesome. Periodically users ask me what my setup is. Usually the user wants...
  • That's one biiiiig polygon
    Something I'm seeing now that WED is in beta: airport layouts with the entire taxiway structure made from one really complex polygon. I...
  • Caught With My Pants Down
    My friends say I have become a technological curmudgeon...whenever a new gadget or device or operating system comes out, I just grumble abo...
  • Who Am I?
    This week we've seen an increase in questions from new users, potential customers (both in the consumer and professional spaces) and thi...
  • Mirrored Normal Maps
    Normal maps in X-Plane 940 have a funny property: if you flip the normal map horizontally or vertically, the bumps change direction. Things...
  • What is a panel region?
    X-Plane 9 introduces a new OBJ feature: panel regions. The basic idea is this: In X-Plane 8 you could use the 2-d panel as a texture in you...
  • The Future of WED
    WED 1.0 has gone RC . The on ly change from beta 5 is that I have the latest manual changes from Tom (including Cormac's illustrations ...
  • The 3-d Panel Is Not Always Necessary
    There is no need to use the 3-d panel if you only want 3-d cockpit. That might be the most counter-intuitive statement in the entire univers...
  • OS X 10.6.3 Performance
    OS X 10.6.3 is out. Besides adding a bunch of OpenGL extensions*, it looks like vertex performance is improved on nVidia hardware. My quic...
  • Bad Alloc Crashes in 920 - Bad Timing
    I just received a series of reports today that certain converted scenery will cause X-Plane to crash with a "bad alloc" error. Ba...

Categories

  • absurdly cute
  • Air Traffic Control
  • aircraft
  • Android
  • animation
  • announce
  • cockpits
  • documentation
  • drivers
  • file formats
  • global scenery
  • Goofy Screenshots
  • hacks
  • hardware
  • hobbies
  • inside x-plane
  • installer
  • ipad
  • iphone
  • legal
  • localization
  • modeling
  • off topic
  • palm pre
  • panels
  • performance
  • plugins
  • political
  • scenery system
  • tools
  • X-Plane 10
  • XSquawkBox

Blog Archive

  • ►  2011 (12)
    • ►  February (1)
    • ►  January (11)
  • ▼  2010 (111)
    • ►  December (4)
    • ►  November (4)
    • ►  October (10)
    • ►  September (9)
    • ►  August (12)
    • ►  July (8)
    • ►  June (4)
    • ►  May (13)
    • ▼  April (13)
      • Baking and Overlays
      • What's Next for Scenery Tools
      • New Tools This Week
      • System Requirements for Scenery Tools
      • What an Evil Disaster
      • Two-Sided Drawing and Up-Normals
      • Ray Tracing is the Technology of the Future...
      • Ray Tracing: Shoot Before You Fly
      • Yes, the iPad is Magical
      • Need...More...Stripes!
      • Mirrored Normal Maps
      • The Real Deal
      • X-Plane 10 Will Be For the iPad Only
    • ►  March (11)
    • ►  February (12)
    • ►  January (11)
  • ►  2009 (130)
    • ►  December (16)
    • ►  November (11)
    • ►  October (6)
    • ►  September (16)
    • ►  August (12)
    • ►  July (11)
    • ►  June (9)
    • ►  May (5)
    • ►  April (10)
    • ►  March (9)
    • ►  February (9)
    • ►  January (16)
  • ►  2008 (147)
    • ►  December (18)
    • ►  November (10)
    • ►  October (7)
    • ►  September (11)
    • ►  August (15)
    • ►  July (9)
    • ►  June (14)
    • ►  May (9)
    • ►  April (14)
    • ►  March (13)
    • ►  February (6)
    • ►  January (21)
  • ►  2007 (100)
    • ►  December (17)
    • ►  November (13)
    • ►  October (13)
    • ►  September (9)
    • ►  August (17)
    • ►  July (7)
    • ►  June (4)
    • ►  May (6)
    • ►  April (9)
    • ►  March (2)
    • ►  February (3)
Powered by Blogger.

About Me

Unknown
View my complete profile