make dynamic sprite better

This commit is contained in:
Corwin 2023-05-06 22:45:05 +01:00
parent e8479c093b
commit f95d68187b
No known key found for this signature in database
2 changed files with 60 additions and 21 deletions

View file

@ -368,4 +368,11 @@ impl Size {
Size::S32x64 => (32, 64),
}
}
#[must_use]
/// Returns the width and height of the size in pixels.
pub const fn to_tiles_width_height(self) -> (usize, usize) {
let wh = self.to_width_height();
(wh.0 / 8, wh.1 / 8)
}
}

View file

@ -1,6 +1,11 @@
use core::ptr::NonNull;
use core::{alloc::Allocator, ptr::NonNull};
use alloc::rc::{Rc, Weak};
use alloc::{
alloc::Global,
boxed::Box,
rc::{Rc, Weak},
vec::Vec,
};
use crate::{
agb_alloc::{block_allocator::BlockAllocator, bump_allocator::StartEnd},
@ -285,34 +290,61 @@ impl Default for SpriteLoader {
}
/// Sprite data that can be used to create sprites in vram.
pub struct DynamicSprite<'a> {
data: &'a [u8],
pub struct DynamicSprite<A: Allocator = Global> {
data: Box<[u8], A>,
size: Size,
}
impl DynamicSprite<'_> {
impl DynamicSprite {
#[must_use]
/// Creates a new dynamic sprite from underlying bytes. Note that despite
/// being an array of u8, this must be aligned to at least a 2 byte
/// boundary.
pub fn new(data: &[u8], size: Size) -> DynamicSprite {
let ptr = &data[0] as *const _ as usize;
if ptr % 2 != 0 {
panic!("data is not aligned to a 2 byte boundary");
}
if data.len() != size.number_of_tiles() * BYTES_PER_TILE_4BPP {
panic!(
"data is not of expected length, got {} expected {}",
data.len(),
size.number_of_tiles() * BYTES_PER_TILE_4BPP
);
/// Creates a new dynamic sprite.
pub fn new(size: Size) -> Self {
Self::new_in(size, Global)
}
}
impl<A: Allocator> DynamicSprite<A> {
#[must_use]
/// Creates a new dynamic sprite of a given size in a given allocator.
pub fn new_in(size: Size, allocator: A) -> Self {
let num_bytes = size.number_of_tiles() * BYTES_PER_TILE_4BPP;
let mut data = Vec::with_capacity_in(num_bytes, allocator);
data.resize(num_bytes, 0);
let data = data.into_boxed_slice();
DynamicSprite { data, size }
}
/// Set the pixel of a sprite to a given paletted pixel. Panics if the
/// coordinate is out of range of the sprite or if the paletted pixel is
/// greater than 4 bits.
pub fn set_pixel(&mut self, x: usize, y: usize, paletted_pixel: usize) {
assert!(paletted_pixel < 0x10);
let (sprite_pixel_x, sprite_pixel_y) = self.size.to_width_height();
assert!(x < sprite_pixel_x, "x too big for sprite size");
assert!(y < sprite_pixel_y, "y too big for sprite size");
let (sprite_tile_x, _) = self.size.to_tiles_width_height();
let (adjust_tile_x, adjust_tile_y) = (x / 8, y / 8);
let tile_number_to_modify = adjust_tile_x + adjust_tile_y * sprite_tile_x;
let byte_to_modify_in_tile = x / 2 + y * 4;
let byte_to_modify = tile_number_to_modify * BYTES_PER_TILE_4BPP + byte_to_modify_in_tile;
let mut byte = self.data[byte_to_modify];
let parity = (x & 0b1) * 4;
byte = (byte & !(0b1111 << parity)) | ((paletted_pixel as u8) << parity);
self.data[byte_to_modify] = byte;
}
/// Tries to copy the sprite to vram to be used to set object sprites.
pub fn try_vram(&self, palette: PaletteVram) -> Result<SpriteVram, LoaderError> {
SpriteVram::new(self.data, self.size, palette)
SpriteVram::new(&self.data, self.size, palette)
}
#[must_use]