+ Filter: implement drawing optimization
+ Filter: implement drawing optimization

adiknoth/calf,adiknoth/calf,zamaudio/calf-LR4,adiknoth/calf,zamaudio/calf-LR4,jnetterf/calf,jnetterf/calf,zamaudio/calf-LR4,jnetterf/calf,zamaudio/calf-LR4,jnetterf/calf,jnetterf/calf,zamaudio/calf-LR4,adiknoth/calf,adiknoth/calf