Fix bug with fillScreen and re-implement colour correction

Forgot to implement this two years ago... nobody noticed.

ESP32-RGB64x32MatrixPanel-I2S-DMA.cpp

@@ -52,6 +52,18 @@
     
 */
 
+
+// For development testing only
+//#define IGNORE_REFRESH_RATE 1
+
+
+
+uint8_t val2PWM(int val) {
+    if (val<0) val=0;
+    if (val>255) val=255;
+    return lumConvTab[val];
+}
+
 bool RGB64x32MatrixPanel_I2S_DMA::allocateDMAmemory()
 {
 
@@ -143,14 +155,17 @@ bool RGB64x32MatrixPanel_I2S_DMA::allocateDMAmemory()
    *         Credit to SmartMatrix for this stuff.
    */    
    
+
     // Calculate what color depth is actually possible based on memory avaialble vs. required dma linked-list descriptors.
     // aka. Calculate the lowest LSBMSB_TRANSITION_BIT value that will fit in memory
     int numDMAdescriptorsPerRow = 0;
     lsbMsbTransitionBit = 0;
+	
+   #ifndef IGNORE_REFRESH_RATE	
     while(1) {
         numDMAdescriptorsPerRow = 1;
         for(int i=lsbMsbTransitionBit + 1; i<PIXEL_COLOR_DEPTH_BITS; i++) {
-            numDMAdescriptorsPerRow += 1<<(i - lsbMsbTransitionBit - 1);
+            numDMAdescriptorsPerRow += (1<<(i - lsbMsbTransitionBit - 1));
         }
 
         int ramrequired = numDMAdescriptorsPerRow * ROWS_PER_FRAME * _num_frame_buffers * sizeof(lldesc_t);
@@ -169,6 +184,7 @@ bool RGB64x32MatrixPanel_I2S_DMA::allocateDMAmemory()
     }
 
     Serial.printf("Raised lsbMsbTransitionBit to %d/%d to fit in remaining RAM\r\n", lsbMsbTransitionBit, PIXEL_COLOR_DEPTH_BITS - 1);
+	#endif
 
     // calculate the lowest LSBMSB_TRANSITION_BIT value that will fit in memory that will meet or exceed the configured refresh rate
     while(1) {           
@@ -201,13 +217,14 @@ bool RGB64x32MatrixPanel_I2S_DMA::allocateDMAmemory()
 
     Serial.printf("Raised lsbMsbTransitionBit to %d/%d to meet minimum refresh rate\r\n", lsbMsbTransitionBit, PIXEL_COLOR_DEPTH_BITS - 1);
 	
+
   /***
    * Step 2a: lsbMsbTransition bit is now finalised - recalculate the DMA descriptor count required, which is used for
    *          memory allocation of the DMA linked list memory structure.
    */          
     numDMAdescriptorsPerRow = 1;
     for(int i=lsbMsbTransitionBit + 1; i<PIXEL_COLOR_DEPTH_BITS; i++) {
-        numDMAdescriptorsPerRow += 1<<(i - lsbMsbTransitionBit - 1);
+        numDMAdescriptorsPerRow += (1<<(i - lsbMsbTransitionBit - 1));
     }
 
     // Refer to 'DMA_LL_PAYLOAD_SPLIT' code in configureDMA() below to understand why this exists.
@@ -366,7 +383,11 @@ void RGB64x32MatrixPanel_I2S_DMA::configureDMA(int r1_pin, int  g1_pin, int  b1_
             // we need 2^(i - LSBMSB_TRANSITION_BIT - 1) == 1 << (i - LSBMSB_TRANSITION_BIT - 1) passes from i to MSB
             //Serial.printf("buffer %d: repeat %d times, size: %d, from %d - %d\r\n", current_dmadescriptor_offset, 1<<(i - lsbMsbTransitionBit - 1), (PIXEL_COLOR_DEPTH_BITS - i), i, PIXEL_COLOR_DEPTH_BITS-1);
 
-            for(int k=0; k < 1<<(i - lsbMsbTransitionBit - 1); k++) 
+          #if SERIAL_DEBUG  
+            Serial.printf("configureDMA(): DMA Loops for PIXEL_COLOR_DEPTH_BITS %d is: %d.\r\n", i, (1<<(i - lsbMsbTransitionBit - 1)));
+          #endif  
+
+            for(int k=0; k < (1<<(i - lsbMsbTransitionBit - 1)); k++) 
             {
                 link_dma_desc(&dmadesc_a[current_dmadescriptor_offset], previous_dmadesc_a, &(fb_malloc_ptr[0].rowdata[fb_malloc_j].rowbits[i].data), sizeof(rowBitStruct) * (PIXEL_COLOR_DEPTH_BITS - i));
                 previous_dmadesc_a = &dmadesc_a[current_dmadescriptor_offset];
@@ -451,6 +472,20 @@ void RGB64x32MatrixPanel_I2S_DMA::updateMatrixDMABuffer(int16_t x_coord, int16_t
       return;
     }
 	
+	/* LED Brightness Compensation. Because if we do a basic "red & mask" for example, 
+	 * we'll NEVER send the dimmest possible colour, due to binary skew.
+	   
+	   i.e. It's almost impossible for color_depth_idx of 0 to be sent out to the MATRIX unless the 'value' of a color is exactly '1'
+	   
+	 */	 
+	red 	= lumConvTab[red];
+	green 	= lumConvTab[green];
+	blue 	= lumConvTab[blue]; 	
+/*	 
+	red 	= val2PWM(red);
+	green 	= val2PWM(green);
+	blue 	= val2PWM(blue);
+*/
 	#ifdef SPLIT_MEMORY_MODE
 	#ifdef SERIAL_DEBUG 
 	int tmp_y_coord = y_coord;
@@ -475,6 +510,7 @@ void RGB64x32MatrixPanel_I2S_DMA::updateMatrixDMABuffer(int16_t x_coord, int16_t
         paint_top_half = false;
     }
        
+	
     for(int color_depth_idx=0; color_depth_idx<PIXEL_COLOR_DEPTH_BITS; color_depth_idx++)  // color depth - 8 iterations
     {
         uint16_t mask = (1 << color_depth_idx); // 24 bit color
@@ -562,6 +598,15 @@ void RGB64x32MatrixPanel_I2S_DMA::updateMatrixDMABuffer(int16_t x_coord, int16_t
           tmp_x_coord += 1;
         } // end reordering
 		
+		/*
+		// Development / testing code only.
+		Serial.printf("r value of %d, color depth: %d, mask: %d\r\n", red,	color_depth_idx, mask);
+		if (red & mask) { Serial.println("Success - Binary"); v|=BIT_R1; }
+		Serial.printf("val2pwm r value:  %d\r\n", val2PWM(red));
+		if (val2PWM(red) & mask) { Serial.println("Success - PWM"); v|=BIT_R2; }
+		*/
+		
+                 
         if (paint_top_half)
         { // Need to copy what the RGB status is for the bottom pixels
 
@@ -618,6 +663,16 @@ void RGB64x32MatrixPanel_I2S_DMA::updateMatrixDMABuffer(uint8_t red, uint8_t gre
 {
   if ( !everything_OK ) return;
   
+	/* https://ledshield.wordpress.com/2012/11/13/led-brightness-to-your-eye-gamma-correction-no/ */	 
+	/*
+	red 	= val2PWM(red);
+	green 	= val2PWM(green);
+	blue 	= val2PWM(blue);  
+	*/
+	red 	= lumConvTab[red];
+	green 	= lumConvTab[green];
+	blue 	= lumConvTab[blue]; 	
+
   for (unsigned int matrix_frame_parallel_row = 0; matrix_frame_parallel_row < ROWS_PER_FRAME; matrix_frame_parallel_row++) // half height - 16 iterations
   {	
     for(int color_depth_idx=0; color_depth_idx<PIXEL_COLOR_DEPTH_BITS; color_depth_idx++)  // color depth - 8 iterations
@@ -698,9 +753,9 @@ void RGB64x32MatrixPanel_I2S_DMA::updateMatrixDMABuffer(uint8_t red, uint8_t gre
           }
           
           // Top and bottom matrix MATRIX_ROWS_IN_PARALLEL half colours
-          if (green & mask) { v|=BIT_G1; v|=BIT_R2; }
+          if (green & mask) { v|=BIT_G1; v|=BIT_G2; }
-          if (blue & mask)  { v|=BIT_B1; v|=BIT_G2; }
+          if (blue & mask)  { v|=BIT_B1; v|=BIT_B2; }
-          if (red & mask)   { v|=BIT_R1; v|=BIT_B2; }
+          if (red & mask)   { v|=BIT_R1; v|=BIT_R2; }
           
           // 16 bit parallel mode
           //Save the calculated value to the bitplane memory in reverse order to account for I2S Tx FIFO mode1 ordering

ESP32-RGB64x32MatrixPanel-I2S-DMA.h

@@ -173,6 +173,13 @@ typedef struct rgb_24 {
 } rgb_24;
 
 
+/***************************************************************************************/   
+// Used by val2PWM
+//C/p'ed from https://ledshield.wordpress.com/2012/11/13/led-brightness-to-your-eye-gamma-correction-no/
+// Example calculator: https://gist.github.com/mathiasvr/19ce1d7b6caeab230934080ae1f1380e
+const uint16_t lumConvTab[]={ 
+    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3, 4, 4, 4, 4, 4, 5, 5, 5, 5, 5, 6, 6, 6, 6, 6, 7, 7, 7, 7, 8, 8, 8, 8, 9, 9, 9, 10, 10, 10, 11, 11, 11, 12, 12, 12, 13, 13, 13, 14, 14, 14, 15, 15, 16, 16, 17, 17, 17, 18, 18, 19, 19, 20, 20, 21, 21, 22, 22, 23, 23, 24, 24, 25, 25, 26, 27, 27, 28, 28, 29, 30, 30, 31, 31, 32, 33, 33, 34, 35, 35, 36, 37, 38, 38, 39, 40, 41, 41, 42, 43, 44, 45, 45, 46, 47, 48, 49, 50, 51, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 73, 74, 75, 76, 77, 78, 80, 81, 82, 83, 84, 86, 87, 88, 90, 91, 92, 93, 95, 96, 98, 99, 100, 102, 103, 105, 106, 107, 109, 110, 112, 113, 115, 116, 118, 120, 121, 123, 124, 126, 128, 129, 131, 133, 134, 136, 138, 139, 141, 143, 145, 146, 148, 150, 152, 154, 156, 157, 159, 161, 163, 165, 167, 169, 171, 173, 175, 177, 179, 181, 183, 185, 187, 189, 192, 194, 196, 198, 200, 203, 205, 207, 209, 212, 214, 216, 218, 221, 223, 226, 228, 230, 233, 235, 238, 240, 243, 245, 248, 250, 253, 255, 255};
+
 /***************************************************************************************/   
 #ifdef USE_GFX_ROOT
 class RGB64x32MatrixPanel_I2S_DMA : public GFX {
@@ -252,6 +259,7 @@ class RGB64x32MatrixPanel_I2S_DMA : public Adafruit_GFX {
     virtual void drawPixel(int16_t x, int16_t y, uint16_t color);   // overwrite adafruit implementation
     virtual void fillScreen(uint16_t color);                        // overwrite adafruit implementation
             void clearScreen() { fillScreen(0); } 
+	void fillScreenRGB888(uint8_t r, uint8_t g, uint8_t b);
     void drawPixelRGB565(int16_t x, int16_t y, uint16_t color);
     void drawPixelRGB888(int16_t x, int16_t y, uint8_t r, uint8_t g, uint8_t b);
     void drawPixelRGB24(int16_t x, int16_t y, rgb_24 color);
@@ -367,6 +375,11 @@ inline void RGB64x32MatrixPanel_I2S_DMA::fillScreen(uint16_t color)  // adafruit
   updateMatrixDMABuffer(r, g, b); // the RGB only (no pixel coordinate) version of 'updateMatrixDMABuffer'
 } 
 
+inline void RGB64x32MatrixPanel_I2S_DMA::fillScreenRGB888(uint8_t r, uint8_t g,uint8_t b)  // adafruit virtual void override
+{
+  updateMatrixDMABuffer(r, g, b);
+} 
+
 // For adafruit
 inline void RGB64x32MatrixPanel_I2S_DMA::drawPixelRGB565(int16_t x, int16_t y, uint16_t color) 
 {

library.json

@@ -10,13 +10,13 @@
     "name": "Faptastic",
     "url": "https://github.com/mrfaptastic/"
   },
-  "version": "1.1.0",
+  "version": "1.2.0",
   "frameworks": "arduino",
   "platforms": "esp32",
   "examples": [
-    "examples/AnimatedGIF/*.ino",
+    "examples/AnimatedGIFPanel/*.ino",
-    "examples/AnimatedGIF/*.cpp",
+    "examples/AnimatedGIFPanel/*.cpp",
-    "examples/AnimatedGIF/*.h",	
+    "examples/AnimatedGIFPanel/*.h",	
     "examples/AuroraDemo/*.ino",
     "examples/AuroraDemo/*.cpp",
     "examples/AuroraDemo/*.h",	

library.properties

@@ -1,5 +1,5 @@
 name=ESP32 64x32 LED MATRIX HUB75 DMA Display
-version=1.1.0
+version=1.2.0
 author=Faptastic
 maintainer=Faptastic 
 sentence=Experimental DMA based LED Matrix HUB75 Library