If you need a depth buffer or use the DEPTH_BUFFER_BIT flag in WebGL for 2D and/or parallax...

Depth vs Position...

The depth buffer is ignored depending the X/Y position using an orthographic projection...

How to acquire mapbox-gl-js z-buffer...

Distorted output when I apply projection OpenGL...

how to retrieve z depth and color of a rendered pixel...

Use default framebuffer depth buffer in a fbo...

What is wrong with my Z-buffer calculations?...

Wireframe rendering with depth-buffer in deferred rendering...

Mixing GL_ALWAYS with GL_LESS in OpenGl...

Prioritizing selected line objects over others by manipulating gl_FragDepth...

WebGL 3d usage for depth sorting 2d objects...

OpenGL - Shadow map/Depth Map giving weird result...

Populating the depth buffer based on a 2D visual produced from a software renderer...

Depth buffer is not filled with data in shadow map render pass...

Linearize depth...

Implementing depth testing for semi-transparent objects...

Rendering artefacts on torus...

Drawing a triangle in 3D to a depth buffer...

CG shader, control Z-Write per fragment?...

precision in Depth buffer on OpenGL ES...

Depth Buffer Clear Behavior between Draw Calls?...

Multi-sampling Frame Render Objects and Depth Buffers...

OpenGL GL_DEPTH_TEST vs glDepthFunc and glDepthMask?...

Depth testing is not working at all...

Merging two separate framebuffers onto default framebuffer after depth testing...

Performance gain of glColorMask()/glDepthMask() on modern hardware?...

DirectX + GLM Depth Reconstruction issues...

Create depth buffer histogram texture with GLSL...

Kinect V2 Depth Frame Pixel Size...