Depth buffer in UUSL

[angus]

I can't seem to figure out how to access the depth buffer in UUSL in my fragment shader. Is it possible to do? I want to get a Z value for a pixel

[silent]

Hi Angus,

 

Getting the depth buffer is depends on task that you are trying to achieve.

 

1. If you are trying to read depth in deferred pass - it's not possible in DX11 / OpenGL render, you will get black texture.
2. In Forward (Ambient pass) you can get access to the opacity depth buffer: opacity_depth texture. You can check the usage in unigine_particles.mat:
   

   <texture unit="11" type="opacity_depth" volume="1"/>
   

   and corresponding fragment shader (core/shaders/particles/fragment/ambient.frag):

   INIT_TEXTURE(11,TEX_DEPTH)

3. For post processing you can get access to the current_depth (transparent + opacity depth) and opacity_depth textures.

 

 

Simple reading from TEX_DEPTH texture will return native depth (as stored on GPU) in R channel. 

getLinearizedDepth(TEX_DEPTH, SCREEN_UV) will return depth in [0, far_plane] range and multiplying by s_depth_range.w will give you normalized depth in [0..1] interval (you can check this calculations in core/shaders/particles/fragment/ambient.frag shader).

 

Thanks!