Questions tagged [stencil-buffer]

9 questions
35
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What is a stencil buffer?

Wikipedia states that a stencil buffer is some arbitrary buffer a shader can use. However, it hints that it's used for clipping, or otherwise "tightly binding" the depth and pixel buffers, slightly contradicting itself. What does the stencil buffer…
6
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2 answers

Uses for Stencil Buffer

I've been doing OpenGL tutorials using LearnOpenGL. Currently I'm reading about Stencil Buffers and in his example he uses a Stencil Buffer to draw an outline around an object. I've also read that it can be used to create shadows and reflections. My…
Archmede
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How much processing power does stenciling actually save?

For example, let's assume I'm rendering cascaded shadow mapping, but for whatever reason, instead of one of the typical approach, I do the following: Render the lowest resolution shadowmap Copy part of the shadowmap to the next shadowmap, covering…
Llamageddon
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selectively setting stencil value based on vertex property in vertex shader

Just like the question says. Is it possible to selectively set the value of the stencil buffer based on a property of a vertex, like the value of its normal, during its vertex processing phase? Instead of setting for all fragments of the model.…
cybergla
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Incorrect values written in stencil buffer

I am trying to pick objects on mouse click. For this I have followed this tutorial, and tried to use the stencil buffer for this purpose. Inside "game" loop I am trying to draw 10 (5 pairs) 'pick'able triangles as follows: ... glClearColor(red,…
Sayan Pal
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Fast clipping without clearing stencil buffer

I'm writing an OpenGL application that runs on a Raspberry Pi, i.e., a quite resource-limited system. Essentially, a few quads with RGBA textures are overlayed/alpha blended on top of each other with individual translation/rotation applied. They are…
2
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1 answer

Layer rendering in Vulkan

I am writing a Vulkan video manipulation engine which has the following layers: Foreground (2D) Scene (3D) Background (2D) Note that each layer may have multiple objects, some of which may be transparent. For 2D objects (foreground and…
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3D model outline using stencil buffer

I'm trying to outline a 3D model in WebGL. I've tried using a stencil buffer techique with glLineWidth and glPolygonMode. However, Mozilla's WebGL reference says that the minimum and maximum widths of lines are 1 (therefore can't be modified). I've…
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Problem using Decaling with Stencil to avoid Z-fighting

I need to create a decaling into a surface like a mesh, and to avoid Z-fighting I've been using Stencil Buffer to Turn-off depth test and make the decaling over the surface the Stencil Op permits. In fact that decaling fails when we turn the camera…