Manage .bmp with alpha channel

[DVill]

Hi,

I would like to manage .bmp (with alpha channel for transparency) stored in flash and show it as it was included in the application via Touchgfx designer.

In other words I would like to customize my application with this bitmap simply uploading the bitmap and not flashing the whole application

At the moment I am able to load from usb .bmp file and store it in a memory portion of the internal flash working as a storing device.

I understand it is possibile to manage dynamical bitmap via the useful tutorial I found in the documentation, but I don't know if it works with .bitmap with alpha channel.

Do you have any suggestion for me?

Best regards.

Davide

[JohanAstrup]

Hello @DVill.

If I understand correctly, this is not solely for development purposes. If it is, there are simpler methods to achieve this than the ones mentioned below.

As I see it, you have two options:

1. Load the image at runtime with a procedure similar to this example:
https://support.touchgfx.com/docs/development/ui-development/scenarios/loading-images-at-runtime#loading-bmp-file-example

2. Use dynamicBitmapCreateExternal:
https://support.touchgfx.com/docs/api/classes/classtouchgfx_1_1_bitmap#dynamicbitmapcreateexternal
This method allows you to include a bitmap from flash that the application does not know at runtime. However, you still need to convert it to a cpp file using the TouchGFX image converter before uploading it to flash.
The advantage of this approach compared to the first one is that you do not need to allocate a bitmap cache for the entire bitmap. Instead, you only require a small cache large enough to hold the dynamic bitmap database.

Best regards,
Johan