A device for decoding video data includes a memory configured to store video data; and one or more processors implemented in circuitry and configured to: determine that a current block of the video data is to be predicted using an angular intra-prediction mode; determine neighboring samples to the current block that will be used to generate a prediction block for the current block according to an angle of the angular intra-prediction mode and that are to be upsampled; calculate predicted samples of the prediction block according to formulas that jointly upsample the neighboring samples that will be used to generate the prediction block and that generate the values for the predicted samples; and decode the current block using the prediction block.