<function name="ClearBuffersObeyStencil" parent="render" type="libraryfunc"> <description>Clears the current rendertarget for obeying the current stencil buffer conditions.</description> <description>Clears the portion of the active Render Target that passes the current stencil buffer conditions.</description> <realm>Client and Menu</realm> <args> <arg name="r" type="number">Value of the **red** channel to clear the current rt with.</arg> <arg name="g" type="number">Value of the **green** channel to clear the current rt with.</arg> <arg name="b" type="number">Value of the **blue** channel to clear the current rt with.</arg> <arg name="a" type="number">Value of the **alpha** channel to clear the current rt with.</arg> <arg name="depth" type="boolean">Clear the depth buffer.</arg> </args> </function> <example> <description>Clearing a section of the screen via the stencil buffer (from [Lex's Stencil Tutorial](https://github.com/Lexicality/stencil-tutorial)).</description> <code> hook.Add( "PostDrawOpaqueRenderables", "Stencil Tutorial Example", function() -- Reset everything to known good render.SetStencilWriteMask( 0xFF ) render.SetStencilTestMask( 0xFF ) render.SetStencilReferenceValue( 0 ) render.SetStencilCompareFunction( STENCIL_ALWAYS ) render.SetStencilPassOperation( STENCIL_KEEP ) render.SetStencilFailOperation( STENCIL_KEEP ) render.SetStencilZFailOperation( STENCIL_KEEP ) render.ClearStencil() -- Enable stencils render.SetStencilEnable( true ) -- Set the reference value to 1. This is what the compare function tests against render.SetStencilReferenceValue( 1 ) -- Refuse to write things to the screen unless that pixel's value is 1 render.SetStencilCompareFunction( STENCIL_EQUAL ) -- Write a 1 to the centre third of the screen. Because we cleared it earlier, everything is currently 0 local w, h = ScrW() / 3, ScrH() / 3 local x_start, y_start = w, h local x_end, y_end = x_start + w, y_start + h render.ClearStencilBufferRectangle( x_start, y_start, x_end, y_end, 1 ) -- Tell the render library to clear the screen, but obeying the stencil test function. -- This means it will only clear the centre third. render.ClearBuffersObeyStencil( 0, 148, 133, 255, false ) -- Let everything render normally again render.SetStencilEnable( false ) end ) </code> <output><image src="clearbuffersobeystencil.jpg" alt="800px"/></output> </example>