Drawing Hidden Lines As Visible Lines

This tutorial explains how to use Pencil+ 3 Material's [Line Functions] / [Draw Hidden Lines as Visible Lines] feature.
[Draw Hidden Lines as Visible Lines] is useful to draw the lines of objects located inside transparent glass without using a [Reflection/Refraction Map].

1. Prepare an object to which Pencil+ 3 Lines are applied.
   In this example, we use the [Teapot] from the [Standard Primitives]. We configure red visible lines on the object and render it.

   
   

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2. Create an object that covers the teapot.
   In this example, we use a [Cylinder] from the [Standard Primitives].
   
   

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3. Apply a material with a reduced [Opacity] to the cylinder object.
   Press the [M] key to open the material editor.
   Set the [Opacity] to 30 and apply the material to the cylinder object.

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4. Render the scene.
   Since the teapot is covered by the cylinder object, the teapot's lines are determined to be [Hidden Lines] and are not drawn.
   

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5. Apply a Pencil+ 3 Material to the opaque material.
   Press the [Type] button to open the [Material/Map Browser].
   Select [Pencil+ 3 Material] in the browser and press [OK].

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6. The [Replace Material] dialog appears.
   Leave [Keep old material as sub-material?] selected and press [OK].
   

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7. Enable [Draw Hidden Lines as Visible Lines].
   Press the [Line Functions] button and activate [Draw Hidden Lines as Visible Lines] located in [Edge Detection].
   

   

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8. Render the scene.
   The red lines applied to the teapot are rendered.
   

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   Tips!

   Lines rendered by [Draw Hidden Lines as Visible Lines] can be output as separate line components using render elements output.

   [Draw Hidden Lines as Visible Lines] is a function that renders as [Visible Lines] objects that were originally processed as [Hidden Lines].
   For this reason, please note that, unlike the case where [Pencil+ 3 Reflection/Refraction map] is used, the line color is not affected by the material's color and opacity.