创建FBX骨骼外观

下左图是 FBX文件导入 3dsMax 之后自动创建的Bone 效果，右图是插件创建骨骼外观之后的效果。

这样处理之后有利于渲染 骨骼动画。

G:\Git_NDTools\Dev_Channel\美术研发部通用技术研发_资源库_批量预览图预览视频\SVN资源中心-批量渲染\骨骼渲染显示-v5.ms

方式也是非常暴力，直接根据骨骼节点父子关系 创建 BOX，然后蒙皮设置权重。

fn _createProxy pBone targetObjOrPos isTerminal finalWidth =
    (
        local p1 = pBone.pos
        local p2 = if isTerminal then targetObjOrPos else targetObjOrPos.pos
        local dist = distance p1 p2
        
        if dist > 0.001 do
        (
            -- Create Mesh
            local meshColor = this._getBoneColor pBone.name
            local geo = Box width:finalWidth length:finalWidth height:dist \
                        widthsegs:1 lengthsegs:1 heightsegs:this.segments \
                        wirecolor:meshColor name:(pBone.name + this.proxySuffix)
            
            -- Align
            geo.transform = this._getMatrixFromZAxis p1 p2
            
            -- Skinning
            --resetScale geo
            addModifier geo (Skin())
            local skinMod = geo.modifiers[#Skin]
            
            -- SkinOps requires selection and modify mode
            select geo
            max modify mode 
            
            if isTerminal then
            (
                -- Terminal/Head: 100% weight to parent only
                skinOps.addBone skinMod pBone 1
            )
            else
            (
                -- Chain: Gradient weight
                skinOps.addBone skinMod pBone 1
                skinOps.addBone skinMod targetObjOrPos 1
                
                local vertCount = skinOps.GetNumberVertices skinMod
                for v = 1 to vertCount do
                (
                    local vPos = getVert geo.mesh v
                    local ratio = vPos.z / dist
                    if ratio < 0 do ratio = 0
                    if ratio > 1 do ratio = 1
                    skinOps.ReplaceVertexWeights skinMod v #(1, 2) #((1.0 - ratio), ratio)
                )
            )
            pBone.renderable = not this.is_hide_bone 
            
            return geo
        )
        return undefined
    ),