ModelSim Altera SDF problem

allright,do not use default sdo files. it is important to take it from your project's folder each time you recompile it; sdo file is actually sdf. quartus compiles it, renames it to sdo and places into your quartus project->simulation->modelsim folder. now when you create your modelsim project elsewhere and simulate it, the modelsim project file somehow finds the correct sdo.

but in time, when you re-launch modelsim simulation it may loose sight of sdo file that was located into your quartus project. i have tried to give address to it, in modelsim there is an option SDF address. i have added the address to sdo file but it didnt work. i guess modelsim project file (.mpf) somehow remembered that sdo file MUST be located into modelsim project's main folder. so; either you copy sdo file from your quartus project/simulation/modelsim to your modelsim project main folder; and it will work fine (but in that case you will have to manually recopy each time you recompile quartus project). OR! you create your modelsim project into yourquartusproject/simulation/modelsim folder. in that case you wont have to copy anything.