VirtualMatrixPanel.ino

/******************************************************************************
    -------------------------------------------------------------------------
    Steps to create a virtual display made up of a chain of panels in a grid
    -------------------------------------------------------------------------

    Read the documentation!
    https://github.com/mrfaptastic/ESP32-HUB75-MatrixPanel-DMA/tree/master/examples/ChainedPanels

    tl/dr:
    
    - Set values for NUM_ROWS, NUM_COLS, PANEL_RES_X, PANEL_RES_Y, PANEL_CHAIN_TYPE. 

    - Other than where the matrix is defined and matrix.begin in the setup, you 
      should now be using the virtual display for everything (drawing pixels, writing text etc).
       You can do a find and replace of all calls if it's an existing sketch
      (just make sure you don't replace the definition and the matrix.begin)

    - If the sketch makes use of MATRIX_HEIGHT or MATRIX_WIDTH, these will need to be 
      replaced with the width and height of your virtual screen. 
      Either make new defines and use that, or you can use virtualDisp.width() or .height()

*****************************************************************************/
// 1) Include key virtual display library
    #include <ESP32-VirtualMatrixPanel-I2S-DMA.h>

// 2) Set configuration
    #define PANEL_RES_X 64 // Number of pixels wide of each INDIVIDUAL panel module. 
    #define PANEL_RES_Y 32 // Number of pixels tall of each INDIVIDUAL panel module.

    #define NUM_ROWS 2 // Number of rows of chained INDIVIDUAL PANELS
    #define NUM_COLS 2 // Number of INDIVIDUAL PANELS per ROW
    #define PANEL_CHAIN NUM_ROWS*NUM_COLS    // total number of panels chained one to another

    /* Configure the serpetine chaining approach. Options are:
        CHAIN_TOP_LEFT_DOWN
        CHAIN_TOP_RIGHT_DOWN
        CHAIN_BOTTOM_LEFT_UP
        CHAIN_BOTTOM_RIGHT_UP

        The location (i.e. 'TOP_LEFT', 'BOTTOM_RIGHT') etc. refers to the starting point where 
        the ESP32 is located, and how the chain of panels will 'roll out' from there.

        In this example we're using 'CHAIN_BOTTOM_LEFT_UP' which would look like this in the real world:

        Chain of 4 x 64x32 panels with the ESP at the BOTTOM_LEFT:

        +---------+---------+
        |    4    |    3    |
        |         |         |
        +---------+---------+
        |    1    |    2    |
        |  (ESP)  |         |
        +---------+---------+      

    */
    #define VIRTUAL_MATRIX_CHAIN_TYPE CHAIN_BOTTOM_LEFT_UP 

// 3) Create the runtime objects to use

    // placeholder for the matrix object
    MatrixPanel_I2S_DMA *dma_display = nullptr;

    // placeholder for the virtual display object
    VirtualMatrixPanel  *virtualDisp = nullptr;


/******************************************************************************
 * Setup!
 ******************************************************************************/
void setup() {
  
  delay(2000);
  Serial.begin(115200);
  Serial.println(""); Serial.println(""); Serial.println("");
  Serial.println("*****************************************************");
  Serial.println(" HELLO !");
  Serial.println("*****************************************************");


  /******************************************************************************
   * Create physical DMA panel class AND virtual (chained) display class.   
   ******************************************************************************/

  /*
    The configuration for MatrixPanel_I2S_DMA object is held in HUB75_I2S_CFG structure,
    All options has it's predefined default values. So we can create a new structure and redefine only the options we need

	Please refer to the '2_PatternPlasma.ino' example for detailed example of how to use the MatrixPanel_I2S_DMA configuration
  */

  HUB75_I2S_CFG mxconfig(
                PANEL_RES_X,   // module width
                PANEL_RES_Y,   // module height
                PANEL_CHAIN    // chain length
  );

  //mxconfig.driver = HUB75_I2S_CFG::FM6126A;     // in case that we use panels based on FM6126A chip, we can set it here before creating MatrixPanel_I2S_DMA object

  // Sanity checks
  if (NUM_ROWS <= 1) {
    Serial.println(F("There is no reason to use the VirtualDisplay class for a single horizontal chain and row!"));
  }

  // OK, now we can create our matrix object
  dma_display = new MatrixPanel_I2S_DMA(mxconfig);

  // let's adjust default brightness to about 75%
  dma_display->setBrightness8(192);    // range is 0-255, 0 - 0%, 255 - 100%

  // Allocate memory and start DMA display
  if( not dma_display->begin() )
      Serial.println("****** !KABOOM! I2S memory allocation failed ***********");

  // create VirtualDisplay object based on our newly created dma_display object
  virtualDisp = new VirtualMatrixPanel((*dma_display), NUM_ROWS, NUM_COLS, PANEL_RES_X, PANEL_RES_Y, VIRTUAL_MATRIX_CHAIN_TYPE);

  // So far so good, so continue
  virtualDisp->fillScreen(virtualDisp->color444(0, 0, 0));
  virtualDisp->drawDisplayTest(); // draw text numbering on each screen to check connectivity

 // delay(1000);

  Serial.println("Chain of 4x 64x32 panels for this example:");
  Serial.println("+---------+---------+");
  Serial.println("|    4    |    3    |");
  Serial.println("|         |         |");
  Serial.println("+---------+---------+");
  Serial.println("|    1    |    2    |");
  Serial.println("| (ESP32) |         |");
  Serial.println("+---------+---------+");

   // draw blue text
   virtualDisp->setFont(&FreeSansBold12pt7b);
   virtualDisp->setTextColor(virtualDisp->color565(0, 0, 255));
   virtualDisp->setTextSize(3); 
   virtualDisp->setCursor(0, virtualDisp->height()- ((virtualDisp->height()-45)/2));    
   virtualDisp->print("ABCD");

   // Red text inside red rect (2 pix in from edge)
   virtualDisp->drawRect(1,1, virtualDisp->width()-2, virtualDisp->height()-2, virtualDisp->color565(255,0,0));

   // White line from top left to bottom right
   virtualDisp->drawLine(0,0, virtualDisp->width()-1, virtualDisp->height()-1, virtualDisp->color565(255,255,255));

   virtualDisp->drawDisplayTest(); // re draw text numbering on each screen to check connectivity
   
}

void loop() {
  

} // end loop


/*****************************************************************************

    Thanks to:

    * Brian Lough for the original example as raised in this issue:
      https://github.com/mrfaptastic/ESP32-HUB75-MatrixPanel-I2S-DMA/issues/26

      YouTube: https://www.youtube.com/brianlough
      Tindie: https://www.tindie.com/stores/brianlough/
      Twitter: https://twitter.com/witnessmenow

    * Galaxy-Man for the kind donation of panels make/test that this is possible:
      https://github.com/Galaxy-Man

*****************************************************************************/