Re: RenderFastPathTriMesh: Triangle strip problem

[Stefan H. <st...@to...>]

>On Oct 14, 2007, at 3:53 PM, Stefan Huber wrote:
>
>>  The combination of kQ3FillStyleEdges and kQ3BackfacingStyleBoth/Flip
>>  produces for large trimeshes (see kMinTrianglesToCache) junk lines
>>  when kQ3RendererPropertyAutomaticTriangleStrips is on and VBOs are
>>  used.
>>
>>  Removing QORenderer::Renderer::RenderFastPathTriMesh line 1010f
>>  (GetCachedTriangleStrip) temporarily "solves" the problem.
>>
>>  The error occurs with Quesa OpenGL when kQ3FillStyleEdges is on and
>>  with Quesa Wireframe and Hiddenline (Wireframe and  Hiddenline are
>>  using glPolygonMode( GL_FRONT_AND_BACK, GL_LINE )).
>
>
>This turned out to be pretty easy to figure out.  In order to create 
>a single triangle strip, the MakeStrip algorithm adds degenerate 
>triangles linking together separate strips.  In the usual filled 
>style, these degenerate triangles are not drawn, but in edge fill 
>style, they cause extra edges.
>
>I have committed a fix, which simply does not use triangle strips in
>the edge fill case.
>

Your fix works well for Quesa OpenGL and Wireframe, thanks. 
Unfortunately Quesa Hiddenline still shows degenerated triangles.

   Stefan
   http://www.topoi.ch