<function name="SetBlend" parent="render" type="libraryfunc"> <description> Sets the alpha blending (or transparency) for upcoming render operations. By itself, this will cause visible overlapping on parts of a model that are in front of other parts of the same model. For a solution to this, see the examples below. <bug issue="3166">This does not affect non-model `render.Draw*` functions.</bug> <note>If a material has the [$alphatest](https://developer.valvesoftware.com/wiki/$alphatest) flag enabled then this function might not behave as expected because alpha will be binary, this has a default cutoff of `0.7`.</note>⤶ </description> <realm>Client</realm> <args> <arg name="blending" type="number"> The alpha (transparency) for upcoming draw operations. A value in the range `(0-1)` where `0` is fully transparent, `0.5` is 50% visible, and `1` is fully opaque. </arg> </args> </function> <example name="Basic Usage (With overlaps)"> <description> This example demonstrates the basic usage of <page>render.SetBlend</page> and the overlapping effect mentioned above. </description> <code> -- Draw at a 75% opacity, so it's mostly opaque. render.SetBlend( 0.75 ) -- Draw the model using the blend we just set. self:DrawModel() -- Draw at a normal opacity again. render.SetBlend( 1 ) </code> <output> <image src="b2b4c/8dc575936095ba3.png" size="436279" name="WithoutDepthExample.png" /> </output> </example> <example name="Avoiding Overlap Issues"> <description> This example demonstrates how the overlapping effect can be avoided with the use of <page>render.OverrideColorWriteEnable</page> </description> <code> -- Prevent drawing to the Color Channel of the currently active Render Target so -- that when we draw the model, it only sets the Depth Buffer values. render.OverrideColorWriteEnable( true, false ) -- Draw the model to set the Depth Buffer values self:DrawModel() -- Start drawing normally again render.OverrideColorWriteEnable( false, false ) -- Draw at a 75% opacity, so it's mostly opaque. render.SetBlend( 0.75 ) -- Draw the model using the blend we just set. -- Because we previously set the Depth Buffer values by drawing the model, and -- because pixels are only drawn when the pixel's current Depth Buffer value is -- less-than or equal-to the draw operation's new Depth value, only the parts of -- the model that are closest to the player's view will be drawn. -- This will prevent the overlapping that normally happens. self:DrawModel() -- Draw at a normal opacity again. render.SetBlend( 1 ) </code> <output> <image src="b2b4c/8dc57594556b659.png" size="431723" name="WithDepthExample.png" /> </output> </example>