image_blp/types/direct/raw3.rs
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use super::super::{
header::{BlpHeader, BlpVersion},
locator::MipmapLocator,
};
#[derive(Debug, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
pub struct BlpRaw3 {
/// The cmap field array is the colour look up table used for an indexed
/// colour model. Each element represents 24 bit RGB colour component values
/// in the order of 0xBBGGRR. The final byte is alignment padding and will
/// not alter the decoded image in any way. One might be able to improve the
/// file compressibility by carefully choosing padding values.
pub cmap: Vec<u32>,
/// Image itself and all mipmaps levels. If there are no mipmaps,
/// the length of the vector is 1.
pub images: Vec<Raw3Image>,
}
impl BlpRaw3 {
/// Predict internal locator to write down mipmaps
pub fn mipmap_locator(&self, version: BlpVersion) -> MipmapLocator {
let mut offsets = [0; 16];
let mut sizes = [0; 16];
let mut cur_offset = BlpHeader::size(version) + self.cmap.len() * 4;
for (i, image) in self.images.iter().take(16).enumerate() {
offsets[i] = cur_offset as u32;
sizes[i] = image.len() as u32;
cur_offset += image.len();
}
MipmapLocator::Internal { offsets, sizes }
}
}
/// Each mipmap contains what appears to be
/// 32 bit BGRA data. `alpha_bits` seems to represent a set of bit flags
/// rather than depth, as all images of this type seem to have 4 bytes per
/// pixel regardless of depth, and it has been seen to exceed 8. Their
/// meaning is unknown.
#[derive(Debug, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
pub struct Raw3Image {
pub pixels: Vec<u32>,
}
impl Raw3Image {
/// Get size in bytes of serialized image
pub fn len(&self) -> usize {
self.pixels.len() * 4
}
pub fn is_empty(&self) -> bool {
self.pixels.is_empty()
}
}