use crate::core;
use guillotiere::{AtlasAllocator, Size};
pub struct Allocator {
raw: AtlasAllocator,
allocations: usize,
}
impl Allocator {
const PADDING: u32 = 1;
pub fn new(size: u32) -> Allocator {
let raw = AtlasAllocator::new(Size::new(size as i32, size as i32));
Allocator {
raw,
allocations: 0,
}
}
pub fn allocate(&mut self, width: u32, height: u32) -> Option<Region> {
let size = self.raw.size();
let padded_width = width + Self::PADDING * 2;
let padded_height = height + Self::PADDING * 2;
let pad_width = padded_width as i32 <= size.width;
let pad_height = padded_height as i32 <= size.height;
let mut allocation = self.raw.allocate(Size::new(
if pad_width { padded_width } else { width } as i32,
if pad_height { padded_height } else { height } as i32,
))?;
if pad_width {
allocation.rectangle.min.x += Self::PADDING as i32;
allocation.rectangle.max.x -= Self::PADDING as i32;
}
if pad_height {
allocation.rectangle.min.y += Self::PADDING as i32;
allocation.rectangle.max.y -= Self::PADDING as i32;
}
self.allocations += 1;
Some(Region {
allocation,
padding: core::Size::new(
if pad_width { Self::PADDING } else { 0 },
if pad_height { Self::PADDING } else { 0 },
),
})
}
pub fn deallocate(&mut self, region: &Region) {
self.raw.deallocate(region.allocation.id);
self.allocations = self.allocations.saturating_sub(1);
}
pub fn is_empty(&self) -> bool {
self.allocations == 0
}
pub fn allocations(&self) -> usize {
self.allocations
}
}
pub struct Region {
allocation: guillotiere::Allocation,
padding: core::Size<u32>,
}
impl Region {
pub fn position(&self) -> (u32, u32) {
let rectangle = &self.allocation.rectangle;
(rectangle.min.x as u32, rectangle.min.y as u32)
}
pub fn size(&self) -> core::Size<u32> {
let size = self.allocation.rectangle.size();
core::Size::new(size.width as u32, size.height as u32)
}
pub fn padding(&self) -> crate::core::Size<u32> {
self.padding
}
}
impl std::fmt::Debug for Allocator {
fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
write!(f, "Allocator")
}
}
impl std::fmt::Debug for Region {
fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
f.debug_struct("Region")
.field("id", &self.allocation.id)
.field("rectangle", &self.allocation.rectangle)
.finish()
}
}