5 Commits (8a5bc2a87c25c55a2c7da347518d707a4649466c)

Author	SHA1	Message	Date
Michael Hanselmann	8a5bc2a87c	waveshare2in13v2: Test updates to both buffers ... Move the logic applying display content changes to both buffers to the "drawImage" function.	4 years ago
Michael Hanselmann	4f995754b0	waveshare213v2: Keep display contents in shadow buffer ... This is necessary for partial updates of the display--not just incremental updates of the full display, but updating part of the display in general. On the horizontal axis only whole bytes can be written, so updates need to be aligned to 8 pixels. One option would be to require the caller of Dev.Draw to only operate at multiples of 8. Another would be to read back the contents of bytes to be updated partially and combine the data. According to the datasheet the controller supports that (command 0x27). The simplest option, however, is to maintain a shadow buffer in the driver. Updates are applied to the buffer from which only the changed destination rectangle is sent to the display. The permanent cost is a bit more than 4kB of memory for a 122x250 display while saving on memory allocations for a temporary image buffer on updates. Signed-off-by: Michael Hanselmann <public@hansmi.ch>	4 years ago
Michael Hanselmann	6052af94b0	waveshare213v2: Move initialization to testable functions	4 years ago
Michael Hanselmann	5179e40adf	waveshare213v2: Use color for clearing ... This is an API-breaking change, albeit a simple one: Previously the Dev.Clear function received a byte named "color". It was sent directly to the display, thus acting more like a pattern to fill the display with. In practice only 0 and 255 are likely to be used. With this change the function is changed to receive a value of type color.Color which is then converted to image1bit.Bit before filling the display. The latter is also given a unittest. Signed-off-by: Michael Hanselmann <public@hansmi.ch>	4 years ago
Michael Hanselmann	ecc1eed386	waveshare213v2: Add support for partial drawing ... When the destination rectangle didn't start at (0,0) or cover the whole display the Dev.Draw function would continue to update the display in full. Obviously that didn't result in a good output. This change updates the drawing logic to only update the affected area (aligned to whole bytes on the horizontal axis) and limits the amount of transferred data to the minimum needed to cover the destination rectangle. The calculation of the various offsets as well as the function sending the image data are written to support unittesting. Signed-off-by: Michael Hanselmann <public@hansmi.ch>	4 years ago