Function SetMaterialConstant

engine/gamesys/src/gamesys/scripts/script_material.cpp:825–858

sets shader constants in a material * Sets shader constants in a material, if the constants exist. * * @name material.set_constants * * @param path [type:hash|string] The path to the resource * @param constants [type:table] A table keyed by constant name with args tables as values. Constants can be partially updated. Supported entries: * * `type` * : [t

     * ```
     */
    static int SetMaterialConstant(lua_State* L, MaterialResource* material_res, dmhash_t name_hash, int args_index)
    {
        args_index = args_index < 0 ? lua_gettop(L) + args_index + 1 : args_index;

        dmRender::HConstant constant;
        if (!dmRender::GetMaterialProgramConstant(material_res->m_Material, name_hash, constant))
        {
            return luaL_error(L, "Material constant '%s' not found", dmHashReverseSafe64(name_hash));
        }

        luaL_checktype(L, args_index, LUA_TTABLE);
        lua_pushvalue(L, args_index);

        dmRenderDDF::MaterialDesc::ConstantType type_from_value = dmRender::GetConstantType(constant);

        g_MaterialModule.m_ScratchValues.SetSize(0);

        GetConstantValuesFromLua(L, &type_from_value, &g_MaterialModule.m_ScratchValues);

        if (g_MaterialModule.m_ScratchValues.Size() != 0)
        {
            dmRender::SetMaterialProgramConstant(material_res->m_Material, name_hash,
                g_MaterialModule.m_ScratchValues.Begin(), g_MaterialModule.m_ScratchValues.Size());
        }

        if (dmRender::GetConstantType(constant) != type_from_value)
        {
            dmRender::SetMaterialProgramConstantType(material_res->m_Material, name_hash, type_from_value);
        }

        lua_pop(L, 1);

        return 0;
    }

    static int Material_SetConstants(lua_State* L)
    {