tux-evse/display-binding-rs

display-binding-rs

Binding template/demo interfacing lvgl-rclib-rs with libafb-rs micro service architecture.

Building dependencies:

• libafb-rs: [email protected]:redpesk/redpesk-common/afb-librust.git
• liblvgl-rs: [email protected]:tux-evse/lvgl-rclib-rs.git

Compiling for frame-buffer

Default driver is frame-buffer, it is typically what is used for embedded devices.

nm /usr/local/lib64/liblv_drivers.so | grep fbdev_init
cargo build

Compiling with GTK emulator

For development and especially for business logic debug with vscode/llgb-gdb, it is far simpler to use GTK than FBDEV.

• Check GTK driver is enabled
• Select GTK by setting USE_GTK=1 environnement variable

nm /usr/local/lib64/liblv_drivers.so | grep gtk_init
USE_GTK=1 cargo build

start display-binding

display-binding/afb-binding/etc/binding-test.sh
firefox --new-window http://localhost:1234

Demo screen on framebuffer

In order to use GTK frame-buffer emulation, you should

• check that kvgl-rclib-rs is installed with GTK enabled
• USE_GTK=1 cargo build

Demo afb-v4 API

Rust LVGL api sample

Check Display::draw_panel within display-lvgl.rs for more samples

Create a label

LvglLabel::new("Label-1", "Tux EvSe UI", 50, 400)
            .set_info("Demo Label widget")
            .set_size(300, 100)
            .set_color(LvglColor::rvb(0, 0, 0))
            .set_background(LvglColor::rvb(0xFF, 0xFF, 0xFF))
            .set_border(3, LvglColor::rvb(0, 0xff, 0))
            .finalize();

Create a button

LvglButton::new("Button-A", "Test-1", 100, 200)
    .set_info("Demo Button 1")
    .set_size(180, 100)
    .finalize();

Faire un screencast du framebuffer

Copy framebuffer and transform it yo PNG. If needed crop image to content with gimp.

cp /dev/fb0 > /tmp/screen.data
RESOLUTION="1920x1080"
ffmpeg -vcodec rawvideo -f rawvideo -pix_fmt rgb32 -s $RESOLUTION -i /tmp/screen.data -f image2 -vcodec png screenshot.png

testing without root privilege

1. In order to test without admin privileges, you need access to

• /dev/fb0 generally with 'video' group
• /dev/input0 usually with 'input' group

2. find which virtual console hold /dev/fb0 framebuffer

• switch virtual console with (Alt+Ctrl+F1) (Alt+Ctrl+F2) ...
• after login check with cat /dev/urandom >/dev/fb0

If your screen is repainted, then you are on /dev/fb0 other wise switch to next virtual console.