How to programme the power on image?

[swq0603 1]

When the machine is power on each time, we can always see that there is a large logo “Ultimaker” on the LCD screen. I just have a look at the firmware and find that it is programmed through a so long code as following. I am just a little curious why the long code indicate the big logo. What code is it?

const uint8_t ultimakerTextGfx[] PROGMEM = {

128, 21, //size

0x6,0x6,0x6,0x6,0xfe,0xfe,0xfe,0xfe,0xfc,0x0,0x0,0x0,0x0,0x0,0x0,0x0,

0xfc,0xfe,0xfe,0xfe,0xfc,0x0,0x0,0x0,0xe,0xfe,0xfe,0xfe,0xfe,0x0,0x0,0xe0,

0xfc,0xfe,0xfe,0xfc,0xe0,0xe0,0x0,0x0,0x0,0xce,0xce,0xce,0x0,0x0,0x0,0xc0,

0xc0,0xc0,0xc0,0xc0,0xc0,0x80,0x0,0x0,0x0,0x0,0x0,0x0,0x80,0xc0,0xc0,0x80,

0x0,0x0,0x0,0x0,0x0,0x0,0x80,0x80,0xc0,0xc0,0xc0,0xc0,0xc0,0xc0,0xc0,0x80,

0x80,0x0,0x0,0x0,0x0,0x6,0xfe,0xfe,0xfe,0xfe,0x0,0x0,0x0,0x0,0x80,0xc0,

0xc0,0xc0,0x0,0x0,0x0,0x0,0x0,0x0,0x80,0x80,0xc0,0xc0,0xc0,0x80,0x80,0x80,

0x0,0x0,0x0,0x0,0xc0,0xc0,0xc0,0xc0,0x0,0x80,0xc0,0xc0,0xc0,0xc0,0x80,0x0,……………………………………

[nallath 1,124]

I'm guessing it's a set of pixels that are either on or off (I didn't make it, so I'm not 100% sure). The logo doesn't have a font in the machine, so this is the only way to do it.

[tinkergnome 927]

I am just a little curious why the long code indicate the big logo. What code is it?

 

I also didn't make it... but it's no secret format...

It's a (sort of) XBM aka X Bitmap.

Commonly used together with the Adafruit GFX-library. There are tools to convert a monochrome bitmap, no need to count the pixels manually...

...for example this one.

What's your intention...?

[swq0603 1]

Firstly Thank you tinkergnome for the answer. I just notice that sometimes the lcd cannot show the logo correctly, not each time，the image cannot be fully shown in the lcd occasionally .Also there is image Dithering sometimes.So I look into the firmware and try finding the reason. I did not change the firmware. I guess if the code is correct, maybe there is a problem with my lcd screen. Not sure whether my thought is correct.