display routines with U8g2

Display.cpp

 void Display::showBrand() {
 	ssd1306.clearDisplay();
 	ssd1306.drawBitmap(0, 0, epd_bitmap_SFTools_Logo, 128, 34, SSD1306_WHITE);
-	ssd1306.setFont(&titillium_web_semibold12pt7b);
-	ssd1306.setTextSize(1);
-	ssd1306.setTextColor(SSD1306_WHITE);
-	uint16_t w = 0, h = 0;
-	calculateWH("Fraestisch N172", w, h);
-	ssd1306.setCursor((SCREEN_WIDTH - w) / 2, 63 - (30 - h) / 2);
-	ssd1306.println("Fraestisch N172");
+
+	char *s = &String("Frästisch N172")[0];
+	int16_t w = 0, h = 0;
+	u8g2_gfx.setFont(u8g2_font_helvB12_tf);
+	w = u8g2_gfx.getUTF8Width(s);
+	h = u8g2_gfx.getFontAscent() - u8g2_gfx.getFontDescent();
+	u8g2_gfx.setForegroundColor(SSD1306_WHITE);
+	u8g2_gfx.setCursor((SCREEN_WIDTH - w) / 2, 63 - (30 - h) / 2);
+	u8g2_gfx.println(F(s));
 	display();
 }
 
 void Display::showInitialization() {
 	ssd1306.clearDisplay();
-	ssd1306.setFont(&titillium_web_semibold12pt7b);
-	ssd1306.setTextSize(1);
-	ssd1306.setTextColor(SSD1306_WHITE);
-	uint16_t w = 0, h = 0;
-	calculateWH("Initialisieren", w, h);
-	ssd1306.setCursor((SCREEN_WIDTH - w) / 2, 30);
-	ssd1306.println("Initialisieren");
-
-	calculateWH(". . . . .", w, h);
-	ssd1306.setCursor((SCREEN_WIDTH - w) / 2, 50);
-	String s = "";
+
+	char *s = &String("Initialisieren")[0];
+	int16_t w = 0;
+	u8g2_gfx.setFont(u8g2_font_helvB12_tf);
+	w = u8g2_gfx.getUTF8Width(s);
+	Serial.println("w: " + String(w));
+	u8g2_gfx.setForegroundColor(SSD1306_WHITE);
+	u8g2_gfx.setCursor((SCREEN_WIDTH - w) / 2, 30);
+	u8g2_gfx.println(F(s));
+
+	char *g;
+	w = u8g2_gfx.getUTF8Width(". . . . .");
+	Serial.println("w: " + String(w));
+	u8g2_gfx.setCursor((SCREEN_WIDTH - w) / 2, 50);
+	String gauge = "";
 	for (int i = 0; i < 6; i++) {
-		ssd1306.print(s);
+		g = &gauge[0];
+		u8g2_gfx.print(g);
 		display();
 		delay(500);
-		if (i < 5) {
-			ssd1306.print(s + ". ");
+		if (i < 4) {
+			gauge = ". ";
+			g = &gauge[0];
 		} else {
-			ssd1306.println(s + ".");
+			gauge = ".";
+			g = &gauge[0];
 		}
 	}
 }
 
 
 void Display::drawStatusText(String txt) {
-	char *s;
-	s = &txt[0];
+	char *s = &txt[0];
 	int16_t w = 0;
 
 	u8g2_gfx.setFont(u8g2_font_helvR08_tf);  // select u8g2 font from here: https://github.com/olikraus/u8g2/wiki/fntlistall
 }
 
 void Display::drawConfigText(String txt) {
-	char *s;
-	s = &txt[0];
+	char *s = &txt[0];
 	int16_t w = 0, h = 0;
 
 	u8g2_gfx.setFont(u8g2_font_helvB12_tf);  // select u8g2 font from here: https://github.com/olikraus/u8g2/wiki/fntlistall
 }
 
 void Display::drawConfigOption(String txt) {
-	char *s;
-	s = &txt[0];
+	char *s = &txt[0];
 	int16_t w = 0, h = 0;
 
 	u8g2_gfx.setFont(u8g2_font_helvB12_tf);