Add Library

libraries/bitluni_ESP32Lib/examples/6BitMode/6BitMode.ino

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+//This example shows a rendering of Julia set. Please change the pinConfig if you are using a different board to PicoVGA
+//cc by-sa 4.0 license
+//bitluni
+
+//include libraries
+#include <ESP32Lib.h>
+#include <Ressources/Font6x8.h>
+
+//VGA Device
+VGA6Bit vga;
+//Pin presets are avaialable for: VGAv01, VGABlackEdition, VGAWhiteEdition, PicoVGA
+const PinConfig &pinConfig = VGA6Bit::PicoVGA;
+
+int taskData[2][3] = 
+  {
+    {0, 0, 160},
+    {0, 160, 320} 
+  };
+
+static float v = -1.5;
+static float vs = 0.001;
+
+//https://en.wikipedia.org/wiki/Julia_set#Pseudocode_for_normal_Julia_sets
+int julia(int x, int y, float cx, float cy)
+{
+  int zx = ((x - 159.5f) * (1.f / 320.f * 5.0f)) * (1 << 12);
+  int zy = ((y - 99.5f) * (1.f / 200.f * 3.0f)) * (1 << 12);
+  int i = 0;
+  const int maxi = 17;
+  int cxi = cx ;
+  int cyi = cy * (1 << 12);
+  while(zx * zx + zy * zy < (4 << 24) && i < maxi) 
+  {
+    int xtemp = (zx * zx - zy * zy) >> 12;
+    zy = ((zx * zy) >> 11) + cyi; 
+    zx = xtemp + cxi;
+    i++;
+  }
+  return i;
+}
+
+int colors[] = {
+  0b110001, 0b110010, 0b110011, 0b100011, 0b010011,
+  0b000011, 0b000111, 0b001011, 0b001111, 0b001110, 0b001101, 
+  0b001100, 0b011100, 0b101100, 0b111100, 0b111000, 0b110100, 
+  0b110000};
+
+void renderTask(void *param)
+{
+  int *data = (int*)param;
+  while(true)
+  {
+    while(!data[0]) delay(1);
+    for(int y = 0; y < 100; y++)
+      for(int x = data[1]; x < data[2]; x++)
+      {
+        int c = colors[julia(x, y, -0.74543f, v)];
+        vga.dotFast(x, y, c);
+        vga.dotFast(319 - x, 199 - y, c);
+      }
+    data[0] = 0;
+  }
+}
+
+//initial setup
+void setup()
+{
+	//initializing i2s vga (with only one framebuffer)
+	vga.init(vga.MODE320x200, pinConfig);
+  TaskHandle_t xHandle = NULL;
+  xTaskCreatePinnedToCore(renderTask, "Render1", 2000, taskData[0],  ( 2 | portPRIVILEGE_BIT ), &xHandle, 0);
+  xTaskCreatePinnedToCore(renderTask, "Render2", 2000, taskData[1],  ( 2 | portPRIVILEGE_BIT ), &xHandle, 1);
+}
+  
+//just draw each frame
+void loop()
+{
+  static unsigned long ot = 0;
+  unsigned long t = millis();
+  unsigned long dt =  t - ot;
+  ot = t;
+  taskData[0][0] = 1;
+  taskData[1][0] = 1;
+  //waiting for task to finish
+  while(taskData[0][0] || taskData[1][0]) delay(1);
+  v += vs * dt;
+  if(v > 1.5f)
+  {
+    v = 1.5f;
+    vs = -vs;
+  }
+  if(v < -1.5f)
+  {
+    v = -1.5f;
+    vs = -vs;
+  }
+}