-- lua
---------------------------------
-- Weight to UV converter v0.5 --
---------------------------------
-- AUTHOR: Zoltan Erdokovy (zoltan.erdokovy@gmail.com)
--
-- USAGE: At the moment the script copies weight values from a hardwired weightmap
-- to a UV set of an also hardwired name. (The names can be changed bellow.) 
-- Weights go to the U axis, so by using a horizontal grayscale gradient, you can
-- emulate a "weight map texture".
--

SourceWeightName = "_SourceWeight"
TargetUVName = "_TargetUV"

SourceWeightMapExist = false
SourceWeightMapIndex = nil
TargetUVExist = false
TargetUVIndex = nil

--                --
-- GETPOINTWEIGHT --
--                --
function GetPointWeight (PointIndex)
     p = nil
     ActVmapType = lxq("query layerservice vmap.type ? "..SourceWeightMapIndex)[1]
     ActVmapName = lxq("query layerservice vmap.name ? "..SourceWeightMapIndex)[1]
     p = lxq("query layerservice vert.vmapValue ? "..PointIndex)
     if p ~= nil then p = p[1]
     else p = 0
     end

     return (p)
end

--            --
-- SETPOINTUV --
--            --
function SetPointUV (PointIndex, value)
     lx("vertMap.setVertex "..TargetUVName.." texture 0 "..PointIndex.." "..value)
end

--             --
-- SELECTLAYER --
--             --

function SelectLayer (LayerIndex)
     lx("select.layer "..LayerIndex.." set")
     lxq("query layerservice layer.name ? "..LayerIndex)
end


--      --
-- MAIN --
--      --

MainLayer = lxq("query layerservice layer.index ? fg")[1]
SelectLayer (MainLayer)

Vertices = lxq("query layerservice verts ? all")   -- Getting the list of vertices.
VertexNum = table.getn(Vertices)

--- Check for required vertex maps. ---
lxq("query layerservice vmap_groups ? all")
for i = 0, (lxq("query layerservice vmap.n ? all")[1])-1 do
     ActVmapType = lxq("query layerservice vmap.type ? "..i)[1]
     ActVmapName = lxq("query layerservice vmap.name ? "..i)[1]
     if (ActVmapType == "weight") and (ActVmapName == SourceWeightName) then
          SourceWeightMapExist = true
          SourceWeightMapIndex = i
     elseif (ActVmapType == "texture") and (ActVmapName == TargetUVName) then
          TargetUVExist = true
          TargetUVIndex = i
     end
end

if (SourceWeightMapExist and TargetUVExist) then
--- Copy weights to UV "U" values. ---
     for j = 0, (VertexNum-1) do      -- Iterating through the vertices.
          ActPointWeight = GetPointWeight(j,WeightMapName)
          if ActPointWeight ~= nil then
               SetPointUV(j,ActPointWeight)
          end
     end
else
     lxout("ERROR: Required vertexmaps not found.")
end