Re: [pygame] opengl from python - drawing wireframe shape colours and contour in the same time

[Paulo Silva <nitrofurano@xxxxxxxxx>]

no, my idea is doing simple poly games, a bit like those 3d games from
Amiga time (such as Robocop3 and many others) - very flatcoloured -
but i really wanted so have the meshes wireframed - thanks for all
useful info! :)

On 7/27/09, Ian Mallett <geometrian@xxxxxxxxx> wrote:
> Yes, unfortunately.  That may be a problem, especially if the object is high
> poly.  There are more complex methods that use shaders.  One of the better
> ones I've found is:
>
> Render the scene to two textures, one RGB and the other depth
> Apply an edge-detection filter to the depth texture (no edge = white, edge =
> black)
> Multiply the two textures together on a fullscreen quad.
>
> The problem here is you'd need shaders if you want to only have one pass,
> which may be overkill.  (MRT to render to both textures simultaneously or
> storing the depth in the alpha channel of the texture).  If you want to use
> fixed function, you'd need two render-to-textures; one for each texture--and
> so there wouldn't really be an advantage to this method over the original
> one.
>
> There's also normal-based edge detection, which I have tried as well.  It's
> simpler, though you'll probably need a shader here too.  This unfortunately
> suffers from line-thickness, which may or may not be a problem.  You'd only
> need one pass though.
>
> HTH,
> Ian
>