Drawing image to screen without internal sd card

[devben]

Hello!
I would like to know if it is possible to draw images or bitmaps to the screen directly
without having to use the internal sd card. I already have a sd card on my teensy 4.1
and want to use it for more than just image data. Maybe I am blind and completely
missed this section of the docs, but even being able to draw pixel by pixel would be fine,
as far as I know a teensy 4.1 at 600Mhz dual core or even overclocking to 800-1Ghz
should be able to run that fine.

The reason for this project is because I don't like how the gameduino can only access image data
from the card and don't want to have to use two sd cards in the process of making my device.
I guess what I'm trying to say is I want to bypass as much of the special functions like bitmaps and similar
as possible as I simply don't need them and want to use this like a normal tft lcd, as it is very cost effective for its  
pixel count and io requirements.

[jamesbowman]

Hi devben,

If your graphics fits in flash memory, then you don't need to use microSD at all. Just embed it in the program code.
gd3asset can process your assets either way: as a header file to #include from your code, or as microSD.

Teensy 4.1 (of course) has a lot of flash memory, so the #include method works really well.

[jamesbowman]

But if you want to load images from the Teensy sd card, you can do something like:


uint8_t buf[256];
size_t n;

GD.cmd_loadimage(0, 0);
<open file>
while (<read n bytes from file into buf>)
 GD.copyram(buf, n);
<close file>

"copyram()" feeds the buffer to the EVE; that's all it takes to load a JPG or PNG image.

[devben]

Thank you, I'll test it as soon as possible