A computer- implemented method, at a display control device, for transforming image data, the method comprising: receiving variable-sized portions (20a, 20b) of compressed image data from a host device, wherein each variable-sized portion (20a, 20b) of image data corresponds to a tile of an image, wherein the image comprises a plurality of tiles in a particular tile order, each tile comprising pixels in a particular pixel order; receiving, from the host device, memory addresses indicating where the variable-sized portions (20a, 20b) of compressed image data should be stored in a memory; receiving, from the host device, a transformed image memory map mapping the memory addresses to a transformed image tile order providing an order in which the tiles should be provided to a display device to display a transformed image; storing the received variable-sized portions of compressed image data in the memory at the received memory addresses; using the transformed image memory map to access the variable-sized portions (20a, 20b) of compressed image data from the memory in the transformed image tile order; decompressing each variable-sized portion (20a, 20b) of compressed image data using a decompression algorithm and storing the decompressed image data in the transformed image tile order; accessing pixels of the decompressed image data in a transformed pixel order to produce a transformed tile having the transformed pixel order; and providing the transformed tiles to the display device for displaying the transformed image, the method further comprising, for subsequent transformed images, receiving updated variable-sized compressed portions of image data from the host device, the updated variable-sized compressed portions of image data corresponding to tiles of a subsequent image that have changed as compared to a previous image, decompressing only the updated variable-sized compressed portions of image data using the decompression algorithm and accessing pixels only of the decompressed image data in the transformed pixel order to produce a transformed tile having the transformed pixel order, and updating the display using the changed transformed tiles to display a subsequent transformed image. receiving variable-sized portions (20a, 20b) of compressed image data from a host device, wherein each variable-sized portion (20a, 20b) of image data corresponds to a tile of an image, wherein the image comprises a plurality of tiles in a particular tile order, each tile comprising pixels in a particular pixel order; receiving, from the host device, memory addresses indicating where the variable-sized portions (20a, 20b) of compressed image data should be stored in a memory; receiving, from the host device, a transformed image memory map mapping the memory addresses to a transformed image tile order providing an order in which the tiles should be provided to a display device to display a transformed image; storing the received variable-sized portions of compressed image data in the memory at the received memory addresses; using the transformed image memory map to access the variable-sized portions (20a, 20b) of compressed image data from the memory in the transformed image tile order; decompressing each variable-sized portion (20a, 20b) of compressed image data using a decompression algorithm and storing the decompressed image data in the transformed image tile order; accessing pixels of the decompressed image data in a transformed pixel order to produce a transformed tile having the transformed pixel order; and providing the transformed tiles to the display device for displaying the transformed image, the method further comprising, for subsequent transformed images, receiving updated variable-sized compressed portions of image data from the host device, the updated variable-sized compressed portions of image data corresponding to tiles of a subsequent image that have changed as compared to a previous image, decompressing only the updated variable-sized compressed portions of image data using the decompression algorithm and accessing pixels only of the decompressed image data in the transformed pixel order to produce a transformed tile having the transformed pixel order, and updating the display using the changed transformed tiles to display a subsequent transformed image.