An example device for decoding video data includes a memory configured to store video data; and one or more processors implemented in circuitry and configured to: generate an intra-prediction block for a current block of video data using an angular intra-prediction mode, the angular intra-prediction mode being an upper-right angular intra-prediction mode or a lower-left angular intra-prediction mode; determine a prediction direction of the angular intra-prediction mode; for at least one sample of the intra-prediction block for the current block: calculate a gradient term for the at least one sample along the prediction direction; and combine a value of an intra-predicted sample of the intra-prediction block at a position of the at least one sample of the intra-prediction block with the gradient term to produce a value of the at least one sample of the intra-prediction block; and decode the current block using the intra-prediction block.