"this is me" <nomail@nomail> wrote in message 
news:web.48556dd8c23a6d99bae00d80@news.povray.org...
> What would be the best way to achieve the following:
>
> Take your average cookie cutter, for example, and instead of it being made 
> of a
> thin band of metal, assume it's made of something thicker, so now what you 
> have
> is an extruded object with a thick cookie cutter outline.  I figured the 
> best
> way to go about making this in POV was to draw the thing in a drawing 
> program,
> and simply fill the interior with a gray color and the border with white. 
> I
> then saved it as a PNG with a black matte around the whole picture.  In 
> POV, I
> used the PNG in a height field, and set the water level to 10/256 so the 
> black
> matte would be ignored.  So there it was, a pretty good rendered version 
> of
> what I had in mind.  Now here's the kicker.  My goal was to make this 
> thing
> pretty relfective - chrome-like - so I made those changes and rerendered. 
> I
> noticed the front face of the object reflected real nice, but when I 
> rotated it
> over to see what the side surfaces looked like, things wheren't so good - 
> it
> wasn't mirror-like.  I guess I was seeing all the triangles that made up 
> the
> height field.  So the question is:  How *do* you make an extruded object 
> that
> looks like it was carved out of polished chrome?
>

It sounds to me like you're describing the sort of shape that POV-Ray prism 
objects create.

The prism object takes an outline that you can make as sophisticated as you 
like and extrudes it upwards by a specified thickness. I've copied an 
example below that draws a humpback bridge symbol.

This symbol was drawn in 2D using Inkscape, which is an open source scalable 
vector graphics editor. Inkscape can save shapes directly as POV-Ray prism 
objects. It also has a nifty 'Trace Bitmap' function, so if you've got the 
shape in another format with a clearly defined edge, it's easy to convert 
into a vector graphic.

Regards,
Chris B.


camera {location <350,500,200> look_at <350,0, 630>}
light_source {   <0,800 ,-100>, rgb 1}


// HumpbackBridge
prism {
    linear_sweep
    bezier_spline
    100, //top
    0, //bottom
    56, //nr points
    /*   0*/ <421.528910, 558.862183>, <421.528910, 558.862183>, 
<421.799480,525.781453>, <421.799480,525.781453>,
    /*   1*/ <421.799480, 525.781453>, <421.799480, 525.781453>, 
<518.970840,525.781453>, <518.970840,525.781453>,
    /*   2*/ <518.970840, 525.781453>, <518.970840, 525.781453>, 
<519.220840,586.629373>, <519.220840,586.629373>,
    /*   3*/ <519.220840, 586.629373>, <483.231220, 585.909583>, 
<470.296890,590.384053>, <459.500000,596.862183>,
    /*   4*/ <459.500000, 596.862183>, <448.703110, 603.520263>, 
<440.972950,619.005923>, <416.500000,628.723123>,
    /*   5*/ <416.500000, 628.723123>, <407.503730, 632.424843>, 
<394.248040,634.849163>, <384.375000,634.849163>,
    /*   6*/ <384.375000, 634.849163>, <374.502200, 634.849163>, 
<362.213520,632.380853>, <353.781250,629.083023>,
    /*   7*/ <353.781250, 629.083023>, <329.308300, 619.365823>, 
<321.578130,603.520263>, <310.781250,596.862183>,
    /*   8*/ <310.781250, 596.862183>, <299.984360, 590.384053>, 
<285.579210,585.909583>, <249.589580,586.629373>,
    /*   9*/ <249.589580, 586.629373>, <249.589580, 586.629373>, 
<249.599220,525.781453>, <249.599220,525.781453>,
    /*  10*/ <249.599220, 525.781453>, <249.599220, 525.781453>, 
<347.505460,525.781453>, <347.505460,525.781453>,
    /*  11*/ <347.505460, 525.781453>, <347.505460, 525.781453>, 
<347.483980,558.862183>, <347.483980,558.862183>,
    /*  12*/ <347.483980, 558.862183>, <350.104080, 576.560923>, 
<366.965320,590.405153>, <384.750000,590.045263>,
    /*  13*/ <384.750000, 590.045263>, <403.615460, 590.225193>, 
<419.068630,574.942913>, <421.528910,558.862183>
  texture {
    pigment {color rgb <1,1,0>}

    finish {reflection 0.9}
  }
}

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