Revision Difference
render.SetStencilPassOperation#561566
<function name="SetStencilPassOperation" parent="render" type="libraryfunc">
<description>
Sets the operation to be performed on the stencil buffer values if the compare function was successful.
Sets the <page text="Stencil Operation">Enums/STENCILOPERATION</page> that will be performed on the Stencil Buffer values of pixels affected by draw operations if the <page text="Compare Function">render.SetStencilCompareFunction</page> Passes the pixel.
For more detailed information on the Stencil system, including usage examples, see the <page text="Stencils Render Reference">render_stencils</page> page
</description>
<realm>Client and Menu</realm>
<args>
<arg name="passOperation" type="number">Pass operation function, see <page>Enums/STENCILOPERATION</page>.</arg>⤶
<arg name="passOperation" type="Enums/STENCILOPERATION">⤶
The Stencil Operation to be performed if the Compare Function Passes a pixel.⤶
</arg>⤶
</args>
</function>
⤶
<image src="b2b4c/8dc4ea87ccd484a.png" size="77518" name="PassOperationFlowChart.png" />⤶
<example>
<description>This uses the pass operation to blank out everything but what we just drew (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 )
-- Only draw things if their pixels are NOT 1. Currently this is everything.
render.SetStencilCompareFunction( STENCIL_NOTEQUAL )
-- If something draws to the screen, set the pixels it draws to 1
render.SetStencilPassOperation( STENCIL_REPLACE )
-- Draw our entities. They will draw as normal
for _, ent in ipairs( ents.FindByClass( "prop_physics" ) ) do
ent:DrawModel()
end
-- At this point, we cannot draw on top of anything that we have already drawn.
-- So, if we flush the screen, our entities will still be there.
render.ClearBuffersObeyStencil( 0, 148, 133, 255, false )
-- Let everything render normally again
render.SetStencilEnable( false )
end )
</code>
<output><image src="basic_pass_operation.jpg" alt="800px"/></output>
</example>