DRAW_MODEL

this callback is called right before a model is drawn and allows to override various stuff

passed into the callback is:

• an instance of the model_context_t

local glow_material = materials.create( "glow_material", [[
      "VertexLitGeneric" {
         "$additive" "1"
         "$envmap" "models/effects/cube_white"
         "$envmaptint" "[1 1 1]"
         "$envmapfresnel" "1"
         "$envmapfresnelminmaxexp" "[0 1 2]"
         "$alpha" "1.0"
      }
   ]]
)

function on_draw_model(ctx)
   if ctx.model_name:find("weapons/v_") == nil then 
      return
   end

   ctx.override_original = true

   glow_material:set_shader_param("$envmaptint", vec3_t(1,1,0))
   glow_material:set_shader_param("$alpha", 0.3)

   ctx:draw_original()
   ctx:draw_material(glow_material)
end

callbacks.add(e_callbacks.DRAW_MODEL, on_draw_model)