Displaying numbers in a sprite on st7789

[brightproject]

Hello @Bodmer
Thanks for your work and the library.
The hardware part of the my project

is the stm32f103c8t6 microcontroller, connected via SPI to a 1.3-inch display with st7789.

Using the following code

#include <TFT_eSPI.h>

TFT_eSPI tft = TFT_eSPI();
TFT_eSprite digit= TFT_eSprite(&tft); 

void setup() {
  // tft.begin();
  tft.init();
  tft.setRotation(0);
}

void loop() {
 digit.setColorDepth(8);
  digit.createSprite(150, 110);
 for (int sensorValue = 0; sensorValue <= 4000; sensorValue += 50) {  
	digit.fillRect  (10, 20, 120, 50, getRpmColor(sensorValue));
	digit.setTextSize(4);
	digit.setTextFont(1); 
	digit.setTextColor(TFT_BLACK);
	digit.setCursor(30, 25);
	digit.print(sensorValue);	 
	digit.setTextColor(TFT_WHITE);	  
	digit.setCursor(28, 23);
	digit.print(sensorValue);
	digit.pushSprite(0, 0);
	delay(10);	  
}
}

uint16_t getRpmColor(int rpm) {
  if (rpm < 2500) {
    return TFT_GREEN;
  } else if (rpm < 3500) {
    return TFT_YELLOW;
  } else {
    return TFT_RED;
  }
}

Numbers on the display, and depending on the numbers, the background color changes.

I make the output through a sprite (in a double buffer), and I encountered a problem that the image is not output if the buffer is larger than 150*110 pixels.
I need a sprite size of 240*240 and I probably won’t be able to get it due to RAM memory limitations.
Is it possible to somehow display the sprite not from the upper left corner, for example in the middle of the display?
I could display a sprite 100*100 in size in the center of the display and that’s enough for me.
And fill the rest of the background with black
tft.fillScreen(TFT_BLACK);

[Bodmer]

You can place the top left corner of the s[rite at any x,y display position:

digit.pushSprite(x, y);

[brightproject]

Hello again, @Bodmer
I'm trying to display an image in a double buffer on the display using STM32F103.
I managed to display two sprites in different places on the display - I figured it out.
I would also like to paint the general background in a certain color, with the usual output
tft.fillScreen(TFT_YELLOW);
I get flickering - which is logical.

flickering.mp4

I try to output two sprites to a third sprite, and still get flickering.
Here is an example in the simulator.

#include <TFT_eSPI.h> // Hardware-specific library

TFT_eSPI tft = TFT_eSPI();  // init display
TFT_eSprite bg = TFT_eSprite(&tft);  // create sprite for background
TFT_eSprite rpm = TFT_eSprite(&tft);  // create sprite for header
TFT_eSprite digit = TFT_eSprite(&tft);  // create sprite for digit

void setup () {

tft.init();
tft.setRotation(1);  // image orientation
tft.fillScreen(TFT_BLACK);

// bg.setColorDepth(8);
bg.createSprite(200, 200);
// bg.setSwapBytes(true);

}

void loop() {


	bg.fillSprite(TFT_YELLOW);
	// bg.fillRect(0, 0, 220, 220, getRpmColor(angleRound));
	// bg.pushSprite(0, 0);
	// bg.deleteSprite();

	rpm.setColorDepth(8);
	rpm.createSprite(85, 30); 
	rpm.fillRect(0, 0, 95, 40, TFT_YELLOW);
	rpm.setTextSize(2);
	// rpm.setFreeFont(FS9);
	// rpm.setFreeFont(FSB9);
	// rpm.setFreeFont(FS12);
	// rpm.setFreeFont(FSB12);
	rpm.setTextColor(TFT_WHITE);
	rpm.setCursor(22, 12);
	rpm.print("RPM");
	rpm.setTextColor(TFT_BLUE);
	rpm.setCursor(20, 10);
	rpm.print("RPM");
	rpm.pushSprite(15, 5);
	// rpm.deleteSprite();

	digit.setColorDepth(8);
	// digit.setFreeFont("micross15");
	digit.createSprite(120, 70); 
	digit.fillRect(0, 0, 120, 70, TFT_YELLOW);
	digit.setTextSize(3);
	// digit.setFreeFont(FSB12);
	// digit.setTextFont(1); 
	digit.setTextColor(TFT_WHITE);
	digit.setCursor(24, 30);
	// digit.print(sensorValue);	 
	// digit.print(angle);	 
	digit.print("1500");	 
	digit.setTextColor(TFT_BLACK);	  
	digit.setCursor(22, 28);
	// digit.print(sensorValue);
	// digit.print(angle);
	digit.print("1500");
	digit.pushSprite(50, 110);
	// digit.deleteSprite();
	// digit.unloadFont();
	rpm.pushToSprite(&bg, 200, 200, TFT_TRANSPARENT);
	// digit.pushRotated(&bg, 0, getRpmColor(angleRound));
	digit.pushToSprite(&bg, 200, 200, TFT_TRANSPARENT);
	// rpm.pushToSprite(&bg, 200, 200, getRpmColor(angleRound));
	bg.pushSprite(0, 0);

}

The simulator certainly has a different microcontroller (more powerful and has SRAM), as well as a more powerful display.
But on my hardware - stm32f103+st7789_240*240, the green or yellow or red background is not displayed at all.

What other methods can I use to get results or is there nothing I can do about it?
I would like to get this result without flickering.

Thanks for your help and library🙂!