Support and Answers >> KML Discussions (read only) Previous   Index   Next   Flat

Bruno_Bowden Master Guide Reged: 03/11/04 Posts: 205 The Answers       10/23/05 05:01 PM Edit   Reply   Quote   Quick Reply   Dear TJ1, you've been doing some pretty good research there. You've accurately established what is significant, so let me explain why it is like this. The winding order for polygons is necessary for determining the direction in which it faces, "the normal". Previously the client would always assume that a polygon was facing upwards, so regardless of the winding order (clockwise or anti-clockwise), the polygon would always appear lit. In the new version of the client, it correctly calculates the direction that a polygon is facing, based on the polygon rather than on the 'upwards' assumption. This is necessary to display the correct lighting on curved surfaces. For more complex geometry, it's virtually impossible for the client to determine is the polygon is intended to be part of the ceiling or floor, so instead we have to rely on the winding order of the polygon to determine the direction for the client. Sorry for the surprise but the ultimate benefit of this is being able to support far more complex and realistic geometry. The client will not change the winding order of a polygon unless you edit the vertices in the client. In that case, it will asume an upwards facing polygon and may flip the winding order on that basis. In any case, it will switch the winding order from clockwise to anti-clockwise. You reported it switching to clockwise ordering? It shouldn't do that, so please send me some reproductions steps for it. Bruno Post Extras

Entire topic Subject Posted by Posted on pseudo-Bug in Polygon fill-color rendering! TJ1 10/22/05 08:18 AM Re: Bug in Polygon fill-color rendering! mcshea98   10/22/05 12:51 PM How to fix lighting of polygons straddling the IDL Bruno_Bowden   10/23/05 05:32 PM Re: How to fix lighting of polygons straddling the xav   10/26/05 08:32 PM Re: Bug in Polygon fill-color rendering! TJ1   10/23/05 09:57 AM Re: Bug in Polygon fill-color rendering! Brian_Flood   10/24/05 07:04 AM Re: Bug in Polygon fill-color rendering! TJ1   10/24/05 09:16 AM Re: Bug in Polygon fill-color rendering! Brian_Flood   10/24/05 10:37 AM The Answers Bruno_Bowden   10/23/05 05:01 PM Re: The Answers cybarber   11/05/05 02:32 PM Re: The Answers TJ1   11/05/05 10:04 PM Re: The Answers TJ1   10/23/05 05:32 PM Re: Bug in Polygon fill-color rendering! TJ1   10/22/05 10:23 AM Re: Bug in Polygon fill-color rendering! Plantech   10/26/05 01:54 PM How is the Polygon winding-direction ascertained? TJ1   10/26/05 09:09 PM Re: How is the Polygon winding-direction ascertain xav   10/26/05 09:21 PM

UBB.threads™ 6.5.1.1