Steam OLED Counter

/*********************************************************************
Code for Bald Engineer Live stream, OLED for DIY DMM. Based on this Adafruit example code.

This is a library for our Monochrome OLEDs based on SSD1305 drivers

  Pick one up today in the adafruit shop!
  ------> https://www.adafruit.com/products/2675

These displays use SPI or I2C to communicate, 3-5 pins are required to
interface

Adafruit invests time and resources providing this open source code,
please support Adafruit and open-source hardware by purchasing
products from Adafruit!

Written by Limor Fried/Ladyada  for Adafruit Industries.
BSD license, check license.txt for more information
All text above, and the splash screen below must be included in any redistribution
*********************************************************************/

#include <Wire.h>
#include <SPI.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1305.h>
#include <Fonts/FreeSans9pt7b.h>
#include <Fonts/FreeSans18pt7b.h>

/* Goals:
1. Use a different font [CHECK]
2. Display counting nubmers from 0.00 to 100.99 [CHECK]
3. Center that horizontally on the display */

/*Pin   LCD     Arduino
DC      4       4
CLK     7       7           [DATA0]
Data1   8       8           [MOSI]
CS      15      10
RESET   16      9 */

// Used for software SPI
#define OLED_CLK 7
#define OLED_MOSI 8

// Used for software or hardware SPI
#define OLED_CS 10
#define OLED_DC 4

// Used for I2C or SPI
#define OLED_RESET 9

// software SPI
Adafruit_SSD1305 display(OLED_MOSI, OLED_CLK, OLED_DC, OLED_RESET, OLED_CS);
// hardware SPI
//Adafruit_SSD1305 display(OLED_DC, OLED_RESET, OLED_CS);

// I2C
//Adafruit_SSD1305 display(OLED_RESET);

#define NUMFLAKES 10
#define XPOS 0
#define YPOS 1
#define DELTAY 2

void fill(unsigned char dat1,unsigned char dat2)
{
  unsigned char x,y;
  for(y=0;y<8;y++)
  {
    display.command(0xb0+y);
    display.command(0x00);
    display.command(0x10);
    for(x=0;x<132;x++)
    {
      display.data(dat1);
      display.data(dat2);
    }
  }
}


void setup()   {
  SerialUSB.begin(9600);
  //delay(500);
  while(!SerialUSB);
  SerialUSB.println("DMM OLED Test with awesome live stream friends!");

  // by default, we'll generate the high voltage from the 3.3v line internally! (neat!)
  display.begin();
  // init done

  // make sure screen is clear
  display.clearDisplay();
  display.display();
  display.setRotation(0);  // rotation 0 is with pin header on top
 }

void alert_display(int count) {
      // invert the display
    for (int x=0; x < count; x++) {
          display.invertDisplay(true);
          delay(250);
          display.invertDisplay(false);
          delay(250);
    }
}

// borrowed from https://forum.arduino.cc/index.php?topic=349764.msg2423911#msg2423911
char *dtostrf (double val, signed char width, unsigned char prec, char *sout) {
    uint32_t iPart = (uint32_t)val;
    uint32_t dPart = (uint32_t)((val - (double)iPart) * pow(10, prec));

    if (dPart < 10)
        sprintf(sout, "%d.0%d", iPart, dPart);  // needs to be zero padded
    else
        sprintf(sout, "%d.%d", iPart, dPart);  // needs to be zero padded

}

void print_reading(char* msg) {


//  SerialUSB.print("x1="); SerialUSB.print(x1); SerialUSB.print(", y1="); SerialUSB.println(y1);
//  SerialUSB.print("w=");  SerialUSB.print(w);  SerialUSB.print(", h=");  SerialUSB.println(h);
    display.setTextColor(WHITE);
    display.setTextWrap(false);

    // find where the Mode Goes
    int16_t  mode_x1, mode_y1;
    uint16_t mode_w, mode_h;
    display.setFont(&FreeSans9pt7b);
    char mode_msg[] = "DC mV";
    display.getTextBounds(mode_msg, 0, 0, &mode_x1, &mode_y1, &mode_w, &mode_h);

    // find where the Value Goes
    int16_t  x1, y1;
    uint16_t w, h;
    display.setFont(&FreeSans18pt7b);
    display.getTextBounds(msg, 0, 0, &x1, &y1, &w, &h);  //x1=3, y1=-25, w=154, h=26
    uint16_t value_centered_width = (128-w) / 2;
    uint16_t value_centered_height = (64-h) - (mode_h/2);

    // clear the display, then print the two things where they should be printed
    display.clearDisplay();
    display.setCursor(value_centered_width,value_centered_height);
    display.setFont(&FreeSans18pt7b);
    display.print(msg); // 10 chars with TextSize(2);
    display.setCursor(0,63);
    display.setFont(&FreeSans9pt7b);
    display.print(mode_msg);
    display.display();

}

void loop() {
    char value_as_string[10];  //Should display 000.00"
    char msg[12];
    int counter = 0;
    for(int x=1; x< 101; x++) {
        //char msg[10];
        //sprintf(msg, "%d.00", x);  //%d6.2 limits width to 6 characters, tenths: %d6.1
    //  float temp_number = 99.0 + (x/100.0);
        float temp_number = x + (random(0,100) / 100.0);
        //int temp_whole = temp_number;
        //int temp_mant = (temp_number - temp_whole) * 100;
        //SerialUSB.print("temp_number: "); SerialUSB.println(temp_number);
        //sprintf(msg, "%s", dtostrf(temp_number));
        dtostrf(temp_number, 5, 2, value_as_string);
        sprintf(msg, "%s", value_as_string);
        //dtostrf(floatvar, StringLengthIncDecimalPoint, numVarsAfterDecimal, charbuf);
        print_reading(msg);
    }

    alert_display(10);
}


void testdrawchar(void) {
  display.setTextSize(1);
  display.setTextWrap(false);
  display.setTextColor(WHITE);
  display.setCursor(0,0);

  for (uint8_t i=0; i < 168; i++) {
    if (i == '\n') continue;
    display.write(i);
    if ((i > 0) && (i % 21 == 0))
      display.println();
  }
  display.display();
}

void testdrawcircle(void) {
  for (uint8_t i=0; i<display.height(); i+=2) {
    display.drawCircle(display.width()/2, display.height()/2, i, WHITE);
    display.display();
  }
}

void testfillrect(void) {
  uint8_t color = 1;
  for (uint8_t i=0; i<display.height()/2; i+=3) {
    // alternate colors
    display.fillRect(i, i, display.width()-i*2, display.height()-i*2, color%2);
    display.display();
    color++;
  }
}

void testdrawtriangle(void) {
  for (uint16_t i=0; i<min(display.width(),display.height())/2; i+=5) {
    display.drawTriangle(display.width()/2, display.height()/2-i,
                     display.width()/2-i, display.height()/2+i,
                     display.width()/2+i, display.height()/2+i, WHITE);
    display.display();
  }
}

void testfilltriangle(void) {
  uint8_t color = WHITE;
  for (int16_t i=min(display.width(),display.height())/2; i>0; i-=5) {
    display.fillTriangle(display.width()/2, display.height()/2-i,
                     display.width()/2-i, display.height()/2+i,
                     display.width()/2+i, display.height()/2+i, WHITE);
    if (color == WHITE) color = BLACK;
    else color = WHITE;
    display.display();
  }
}

void testdrawroundrect(void) {
  for (uint8_t i=0; i<display.height()/3-2; i+=2) {
    display.drawRoundRect(i, i, display.width()-2*i, display.height()-2*i, display.height()/4, WHITE);
    display.display();
  }
}

void testfillroundrect(void) {
  uint8_t color = WHITE;
  for (uint8_t i=0; i<display.height()/3-2; i+=2) {
    display.fillRoundRect(i, i, display.width()-2*i, display.height()-2*i, display.height()/4, color);
    if (color == WHITE) color = BLACK;
    else color = WHITE;
    display.display();
  }
}

void testdrawrect(void) {
  for (uint8_t i=0; i<display.height()/2; i+=2) {
    display.drawRect(i, i, display.width()-2*i, display.height()-2*i, WHITE);
    display.display();
  }
}

void testdrawline() {
  for (uint8_t i=0; i<display.width(); i+=4) {
    display.drawLine(0, 0, i, display.height()-1, WHITE);
    display.display();
  }
  for (uint8_t i=0; i<display.height(); i+=4) {
    display.drawLine(0, 0, display.width()-1, i, WHITE);
    display.display();
  }
  delay(250);

  display.clearDisplay();
  for (uint8_t i=0; i<display.width(); i+=4) {
    display.drawLine(0, display.height()-1, i, 0, WHITE);
    display.display();
  }
  for (int8_t i=display.height()-1; i>=0; i-=4) {
    display.drawLine(0, display.height()-1, display.width()-1, i, WHITE);
    display.display();
  }
  delay(250);

  display.clearDisplay();
  for (int8_t i=display.width()-1; i>=0; i-=4) {
    display.drawLine(display.width()-1, display.height()-1, i, 0, WHITE);
    display.display();
  }
  for (int8_t i=display.height()-1; i>=0; i-=4) {
    display.drawLine(display.width()-1, display.height()-1, 0, i, WHITE);
    display.display();
  }
  delay(250);

  display.clearDisplay();
  for (uint8_t i=0; i<display.height(); i+=4) {
    display.drawLine(display.width()-1, 0, 0, i, WHITE);
    display.display();
  }
  for (uint8_t i=0; i<display.width(); i+=4) {
    display.drawLine(display.width()-1, 0, i, display.height()-1, WHITE);
    display.display();
  }
  delay(250);
}