I'm building a little graphics library using minifb, essentially just drawing pixels to a framebuffer.
Currently, my code for blitting a rectangle to a Texture is as follows:
fn blit(&self, dest: &mut Texture) {
for x: i32 in self.x..self.x+self.width {
for y: i32 in self.y..self.y+self.height {
dest.set(x, y, color: self.color.clone());
// same as dest.pixels[y*dest.width+x]=color
// but this checks for out-of-bound pixels.
}
}
}
Obviously this is very inefficient as I need to loop through each pixel one-by-one.
I wondered if Rust had a method of setting a 'chunk' of the dest.pixels vector to a line of the rectangle pixels? So a single call could update, say, a line of 100 pixels? Something like Vec::update_from(&mut self, index, new_values).
For example, if I had two Vecs as follows:
let a = vec![2, 4, 5, 6, 7, 8, 10];
let b = vec![0, 1, 2];
I'd like to be able to start writing vec b into vec a at a specific index, e.g. index 3 (element 4). So the resulting vec would be [2, 4, 5, 0, 1, 2, 10].
If there is a way to mass-update elements in a vec with a single call, I'd really appreciate it :)
My code for blitting a texture (vec of pixels) to another texture is as follows:
fn blit(&self, dest: &mut Texture) {
for y: i32 in 0i32..self.height as i32 {
for x: i32 in 0i32..self.width as i32 {
dest.set(x: x + self.x, y: y + self.y, color: self.get(x, y).unwrap().clone());
}
}
}
Would it also be possible to write in bulk (rows at a time instead of pixels) for different values?
Any help for either of these would be greatly appreciated, and I'm happy to answer any questions to clarify things.
To Vecs (or more precisely slices), yes, but I don't know about your texture library. Anyway this is copy_from_slice():
a[3..][..b.len()].copy_from_slice(b);