I’m working in a home project, a ZX Spectrum digital cassette (powaDCR). This is based in a Audiokit ESP32 board and Sunton CYD display 3248S035C. I’m doing test with LVGL in order to create the HMI. Only I made two screens, and static bootscreen and main screen with a cassette (entire image) that moves from up to down and dissapiars to the bottom of the display. This movement is very slow, due to frame rate, display refresh is very slow and I don’t achieve to forze the frame rate / refresh display to the maximum possible. (I have a video to show it, but I don’t upload it)
Nice to see a fellow retro-computing bender here. There are many factors that can make a pictorial animation slow. It can come from the software side and/or from the display-side. On the software side you should use a fairly fast CPU to create full-screen animation, and if your board supports some DMA or other 2D-acceleration that might come handy too. Sometimes the LVGL rendering buffer setting to a larger one can make it faster if you have enough memory for that. It matters how big your moved picture is and maybe using lower resolution/depth can lead to faster movement. If the display gets the pixel-data through SPI, the SPI clock-rate can be set, it should be set to the maximum possible, that’s still reliable, preferably on a short cable. If the display and its driver is smart enough to only send the changed pixels, it’s even better. I think you’ll find more tips for making it render faster at LVGL forum if you provide more details about your particular hardware there.