Need to erase some data values

[arunyava]

Hi,
This post was not and issue.
I need some help for clearing the data. I will write some string value to display. for example i wrote WELCOME' string on display. I want to erase E and M on the display. How can i achieve this. Thanks in advance!

[nopnop2002]

If you draw the same character in the same position with the same color as the background color, it will disappear.

// get font width & height
uint8_t buffer[FontxGlyphBufSize];
uint8_t fontWidth;
uint8_t fontHeight;
GetFontx(fx16G, 0, buffer, &fontWidth, &fontHeight);

lcdFillScreen(&dev, BLACK);
strcpy((char *)ascii, "WELCOME");
lcdDrawString(&dev, fx16G, xpos, ypos, ascii, WHITE);
vTaskDelay(1000);
strcpy((char *)ascii, "E");
lcdDrawString(&dev, fx16G, xpos+(fontWidth*1), ypos, ascii, BLACK);
lcdDrawString(&dev, fx16G, xpos+(fontWidth*6), ypos, ascii, BLACK);
strcpy((char *)ascii, "M");
lcdDrawString(&dev, fx16G, xpos+(fontWidth*5), ypos, ascii, BLACK);

[arunyava]

Thank you sir for reply. One more help. How to draw a symbol means bluetooth symbol , battery symbols like that? Is it possible to help me to do that?

[nopnop2002]

A font file is required that contains symbols such as the Bluetooth symbol and battery symbol.

I think that such font files are available on the Internet.

This is a 24x24 font converted from u8g2 library emoticons21.bdf.

This is a 16x16 font converted from u8g2 library Scroll-o-Sprites.bdf.

Font File Editor(FONTX Editor)

There is a font file editor.
This can be done on Windows 10.
You can create your own font files.
Developer page is here.

This is a battery symbol font included in the u8g2 library.

[arunyava]

How can you create this image. Can you simply explain the step.

…

On Wed, Nov 20, 2024 at 7:35 PM nopnop2002 ***@***.***> wrote: A font file is required that contains symbols such as the Bluetooth symbol and battery symbol. I believe that such font files are available on the Internet. bdf-font-2.JPG (view on web) <https://github.com/user-attachments/assets/1c440995-1386-45c1-9976-d5dd39fd5800> — Reply to this email directly, view it on GitHub <#47 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AWMMIKN5XJ5MRKPRODWONBT2BSJJBAVCNFSM6AAAAABRKMHF6GVHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZDIOBYGY3TENJZG4> . You are receiving this because you authored the thread.Message ID: ***@***.***>

-- *Arunya*

[arunyava]

Unable to download FONTX editor

[nopnop2002]

Perhaps your browser is blocking the download zip file.
Please review your browser settings.

You can download fontx editor from here.
http://elm-chan.org/fsw_e.html

[nopnop2002]

I added IconTest example.

I created a PNG file with this.
https://github.com/nopnop2002/esp-idf-st7789/tree/master/battery-image

[arunyava]

Can you explain "This is a 16x16 font converted from u8g2 library Scroll-o-Sprites.bdf." this one?

[nopnop2002]

Import Scroll-o-Sprites.bdf included in the u8g2 library into fontx editor and save it as an FNT file.

Scroll-o-Sprites.bdf is here.

https://github.com/olikraus/u8g2/blob/master/tools/font/pbm/Scroll-o-Sprites.bdf

• download u8g2 library
• start fontx editor
• import Scroll-o-Sprites.bdf
• save as Scroll-o-Sprites.fnt
• copy Scroll-o-Sprites.fnt to fonts directory

    FontxFile fx32S[2];
    InitFontx(fx32S,"/fonts/Scroll-o-Sprites.fnt",""); // 16x16Dot Emoji
    CodeTest(&dev, fx32S, CONFIG_WIDTH, CONFIG_HEIGHT, 0x00, 0xFF);