Expand description
Graphic Device Operations
§Control an existing graphic device
TODO
§Implement a new graphic device
The following two things are needed to implement a graphic device.
- DeviceDriver trait: the actual implementation of graphic device methods.
- DeviceDescriptor struct: the parameters that might differ per device instance (e.g. sizes, and colors).
For example, the following code implements a simple graphic device that shows a message when it’s activated (and ignores everything else).
use extendr_api::{
graphics::{DeviceDescriptor, DeviceDriver, DevDesc},
prelude::*,
};
struct MyDevice<'a> {
welcome_message: &'a str,
}
impl<'a> DeviceDriver for MyDevice<'a> {
fn activate(&mut self, _dd: DevDesc) {
let welcome_message = self.welcome_message;
rprintln!("message from device: {welcome_message}");
}
}
/// Create a new device.
///
/// @export
#[extendr]
fn my_device(welcome_message: String) {
let device_driver = MyDevice {
welcome_message: welcome_message.as_str(),
};
let device_descriptor = DeviceDescriptor::new();
let device = device_driver.create_device::<MyDevice>(device_descriptor, "my device");
}This can be called from R.
my_device("I'm so active!!!")
#> message from device: I'm so active!!!Re-exports§
pub use device_descriptor::*;pub use device_driver::*;
Modules§
Structs§
- A structure containing graphical parameters
- A row-major array of pixels. One pixel is 32-bit, whose each byte represents alpha, blue, green, and red in the order.
Enums§
Functions§
Type Aliases§
- ——— New (in 1.4.0) device driver structure ——— NOTES: