how to change panel height and width values while the program is running

Ahsen · December 4, 2022, 2:32pm

Panel width and height values are set to const. Therefore, I cannot change the panel values again while the program is running. When I delete the const statement, the program gives an error. How can I set the panel values while the program is running, or what other files should I change after deleting the const expression?

Louis · December 4, 2022, 2:34pm

You can’t change them, the library wasn’t designed for dynamic display configuration. For ESP32 only, I have some test code that can configure the display before calling start, but needs a reboot to apply a new config

Ahsen · December 5, 2022, 8:31am

I would like to see these test codes. I would be very happy if you share

b707 · December 5, 2022, 9:13am

I am wondering why do you need to change panel dimensions during program run?

Ahsen · December 5, 2022, 9:29am

Because the end user should be able to increase the panel size whenever he wants. Developed software should offer this option to the user

Louis · December 5, 2022, 9:30am

The code is already in the SmartMatrix Library repo, inside the _NT (no templates) class. Here’s a complicated sketch that uses the _NT class, the most important parts are here:

github.com

Pixelvation/PixelvationEngine_HUB75/blob/master/PixelvationEngine_HUB75.ino#L25-L33


      
          uint16_t kMatrixWidth = 64;       // Set to the width of your display, must be a multiple of 8
          uint16_t kMatrixHeight = 32;      // Set to the height of your display
          uint8_t kRefreshDepth = 36;       // Tradeoff of color quality vs refresh rate, max brightness, and RAM usage.  36 is typically good, drop down to 24 if you need to.  On Teensy, multiples of 3, up to 48: 3, 6, 9, 12, 15, 18, 21, 24, 27, 30, 33, 36, 39, 42, 45, 48.  On ESP32: 24, 36, 48
          uint8_t kDmaBufferRows = 4;       // known working: 2-4, use 2 to save RAM, more to keep from dropping frames and automatically lowering refresh rate.  (This isn't used on ESP32, leave as default)
          uint8_t kPanelType = SM_PANELTYPE_HUB75_32ROW_MOD16SCAN;  // Choose the configuration that matches your panels.  See more details in MatrixCommonHub75.h and the docs: https://github.com/pixelmatix/SmartMatrix/wiki
          uint32_t kMatrixOptions = (SM_HUB75_OPTIONS_NONE);        // see docs for options: https://github.com/pixelmatix/SmartMatrix/wiki
          const uint8_t kBackgroundLayerOptions = (SM_BACKGROUND_OPTIONS_NONE);
          
          
SMARTMATRIX_ALLOCATE_BUFFERS_NT(matrix, kMatrixWidth, kMatrixHeight, kRefreshDepth, kDmaBufferRows, kPanelType, kMatrixOptions);

Louis · December 5, 2022, 9:32am

There’s a good reason why this is not offered, compiling the width/height/etc in to the refresh class increases the efficiency by about 25%, and there are very few reasons why people need to change the parameters at runtime.

Ahsen · December 5, 2022, 11:44am

Thank you very much Louis.

how to change panel height and width values ​​while the program is running

how to change panel height and width values while the program is running