Move prepare_pixels to the canvas thread

Nothing else uses it in the whole crate graph.
This commit is contained in:
Anthony Ramine 2018-11-17 16:41:53 +01:00
parent ca62b5c318
commit 87c849c0d6
5 changed files with 331 additions and 333 deletions

View file

@ -3,11 +3,14 @@
* file, You can obtain one at https://mozilla.org/MPL/2.0/. */
use super::gl_context::{GLContextFactory, GLContextWrapper};
use byteorder::{ByteOrder, NativeEndian, WriteBytesExt};
use canvas_traits::webgl::*;
use euclid::Size2D;
use fnv::FnvHashMap;
use gleam::gl;
use half::f16;
use offscreen_gl_context::{GLContext, GLContextAttributes, GLLimits, NativeGLContextMethods};
use pixels;
use std::thread;
/// WebGL Threading API entry point that lives in the constellation.
@ -1731,3 +1734,327 @@ fn map_dot_separated<F: Fn(&str, &mut String)>(s: &str, f: F) -> String {
}
mapped
}
fn prepare_pixels(
internal_format: TexFormat,
data_type: TexDataType,
size: Size2D<u32>,
unpacking_alignment: u32,
alpha_treatment: Option<AlphaTreatment>,
y_axis_treatment: YAxisTreatment,
tex_source: TexSource,
mut pixels: Vec<u8>,
) -> Vec<u8> {
match alpha_treatment {
Some(AlphaTreatment::Premultiply) => {
if tex_source == TexSource::FromHtmlElement {
premultiply_inplace(TexFormat::RGBA, TexDataType::UnsignedByte, &mut pixels);
} else {
premultiply_inplace(internal_format, data_type, &mut pixels);
}
},
Some(AlphaTreatment::Unmultiply) => {
assert_eq!(tex_source, TexSource::FromHtmlElement);
unmultiply_inplace(&mut pixels);
},
None => {},
}
if tex_source == TexSource::FromHtmlElement {
pixels = rgba8_image_to_tex_image_data(internal_format, data_type, pixels);
}
if y_axis_treatment == YAxisTreatment::Flipped {
// FINISHME: Consider doing premultiply and flip in a single mutable Vec.
pixels = flip_pixels_y(
internal_format,
data_type,
size.width as usize,
size.height as usize,
unpacking_alignment as usize,
pixels,
);
}
pixels
}
/// Translates an image in rgba8 (red in the first byte) format to
/// the format that was requested of TexImage.
fn rgba8_image_to_tex_image_data(
format: TexFormat,
data_type: TexDataType,
mut pixels: Vec<u8>,
) -> Vec<u8> {
// hint for vector allocation sizing.
let pixel_count = pixels.len() / 4;
match (format, data_type) {
(TexFormat::RGBA, TexDataType::UnsignedByte) => pixels,
(TexFormat::RGB, TexDataType::UnsignedByte) => {
for i in 0..pixel_count {
let rgb = {
let rgb = &pixels[i * 4..i * 4 + 3];
[rgb[0], rgb[1], rgb[2]]
};
pixels[i * 3..i * 3 + 3].copy_from_slice(&rgb);
}
pixels.truncate(pixel_count * 3);
pixels
},
(TexFormat::Alpha, TexDataType::UnsignedByte) => {
for i in 0..pixel_count {
let p = pixels[i * 4 + 3];
pixels[i] = p;
}
pixels.truncate(pixel_count);
pixels
},
(TexFormat::Luminance, TexDataType::UnsignedByte) => {
for i in 0..pixel_count {
let p = pixels[i * 4];
pixels[i] = p;
}
pixels.truncate(pixel_count);
pixels
},
(TexFormat::LuminanceAlpha, TexDataType::UnsignedByte) => {
for i in 0..pixel_count {
let (lum, a) = {
let rgba = &pixels[i * 4..i * 4 + 4];
(rgba[0], rgba[3])
};
pixels[i * 2] = lum;
pixels[i * 2 + 1] = a;
}
pixels.truncate(pixel_count * 2);
pixels
},
(TexFormat::RGBA, TexDataType::UnsignedShort4444) => {
for i in 0..pixel_count {
let p = {
let rgba = &pixels[i * 4..i * 4 + 4];
(rgba[0] as u16 & 0xf0) << 8 |
(rgba[1] as u16 & 0xf0) << 4 |
(rgba[2] as u16 & 0xf0) |
(rgba[3] as u16 & 0xf0) >> 4
};
NativeEndian::write_u16(&mut pixels[i * 2..i * 2 + 2], p);
}
pixels.truncate(pixel_count * 2);
pixels
},
(TexFormat::RGBA, TexDataType::UnsignedShort5551) => {
for i in 0..pixel_count {
let p = {
let rgba = &pixels[i * 4..i * 4 + 4];
(rgba[0] as u16 & 0xf8) << 8 |
(rgba[1] as u16 & 0xf8) << 3 |
(rgba[2] as u16 & 0xf8) >> 2 |
(rgba[3] as u16) >> 7
};
NativeEndian::write_u16(&mut pixels[i * 2..i * 2 + 2], p);
}
pixels.truncate(pixel_count * 2);
pixels
},
(TexFormat::RGB, TexDataType::UnsignedShort565) => {
for i in 0..pixel_count {
let p = {
let rgb = &pixels[i * 4..i * 4 + 3];
(rgb[0] as u16 & 0xf8) << 8 |
(rgb[1] as u16 & 0xfc) << 3 |
(rgb[2] as u16 & 0xf8) >> 3
};
NativeEndian::write_u16(&mut pixels[i * 2..i * 2 + 2], p);
}
pixels.truncate(pixel_count * 2);
pixels
},
(TexFormat::RGBA, TexDataType::Float) => {
let mut rgbaf32 = Vec::<u8>::with_capacity(pixel_count * 16);
for rgba8 in pixels.chunks(4) {
rgbaf32.write_f32::<NativeEndian>(rgba8[0] as f32).unwrap();
rgbaf32.write_f32::<NativeEndian>(rgba8[1] as f32).unwrap();
rgbaf32.write_f32::<NativeEndian>(rgba8[2] as f32).unwrap();
rgbaf32.write_f32::<NativeEndian>(rgba8[3] as f32).unwrap();
}
rgbaf32
},
(TexFormat::RGB, TexDataType::Float) => {
let mut rgbf32 = Vec::<u8>::with_capacity(pixel_count * 12);
for rgba8 in pixels.chunks(4) {
rgbf32.write_f32::<NativeEndian>(rgba8[0] as f32).unwrap();
rgbf32.write_f32::<NativeEndian>(rgba8[1] as f32).unwrap();
rgbf32.write_f32::<NativeEndian>(rgba8[2] as f32).unwrap();
}
rgbf32
},
(TexFormat::Alpha, TexDataType::Float) => {
for rgba8 in pixels.chunks_mut(4) {
let p = rgba8[3] as f32;
NativeEndian::write_f32(rgba8, p);
}
pixels
},
(TexFormat::Luminance, TexDataType::Float) => {
for rgba8 in pixels.chunks_mut(4) {
let p = rgba8[0] as f32;
NativeEndian::write_f32(rgba8, p);
}
pixels
},
(TexFormat::LuminanceAlpha, TexDataType::Float) => {
let mut data = Vec::<u8>::with_capacity(pixel_count * 8);
for rgba8 in pixels.chunks(4) {
data.write_f32::<NativeEndian>(rgba8[0] as f32).unwrap();
data.write_f32::<NativeEndian>(rgba8[3] as f32).unwrap();
}
data
},
(TexFormat::RGBA, TexDataType::HalfFloat) => {
let mut rgbaf16 = Vec::<u8>::with_capacity(pixel_count * 8);
for rgba8 in pixels.chunks(4) {
rgbaf16
.write_u16::<NativeEndian>(f16::from_f32(rgba8[0] as f32).as_bits())
.unwrap();
rgbaf16
.write_u16::<NativeEndian>(f16::from_f32(rgba8[1] as f32).as_bits())
.unwrap();
rgbaf16
.write_u16::<NativeEndian>(f16::from_f32(rgba8[2] as f32).as_bits())
.unwrap();
rgbaf16
.write_u16::<NativeEndian>(f16::from_f32(rgba8[3] as f32).as_bits())
.unwrap();
}
rgbaf16
},
(TexFormat::RGB, TexDataType::HalfFloat) => {
let mut rgbf16 = Vec::<u8>::with_capacity(pixel_count * 6);
for rgba8 in pixels.chunks(4) {
rgbf16
.write_u16::<NativeEndian>(f16::from_f32(rgba8[0] as f32).as_bits())
.unwrap();
rgbf16
.write_u16::<NativeEndian>(f16::from_f32(rgba8[1] as f32).as_bits())
.unwrap();
rgbf16
.write_u16::<NativeEndian>(f16::from_f32(rgba8[2] as f32).as_bits())
.unwrap();
}
rgbf16
},
(TexFormat::Alpha, TexDataType::HalfFloat) => {
for i in 0..pixel_count {
let p = f16::from_f32(pixels[i * 4 + 3] as f32).as_bits();
NativeEndian::write_u16(&mut pixels[i * 2..i * 2 + 2], p);
}
pixels.truncate(pixel_count * 2);
pixels
},
(TexFormat::Luminance, TexDataType::HalfFloat) => {
for i in 0..pixel_count {
let p = f16::from_f32(pixels[i * 4] as f32).as_bits();
NativeEndian::write_u16(&mut pixels[i * 2..i * 2 + 2], p);
}
pixels.truncate(pixel_count * 2);
pixels
},
(TexFormat::LuminanceAlpha, TexDataType::HalfFloat) => {
for rgba8 in pixels.chunks_mut(4) {
let lum = f16::from_f32(rgba8[0] as f32).as_bits();
let a = f16::from_f32(rgba8[3] as f32).as_bits();
NativeEndian::write_u16(&mut rgba8[0..2], lum);
NativeEndian::write_u16(&mut rgba8[2..4], a);
}
pixels
},
// Validation should have ensured that we only hit the
// above cases, but we haven't turned the (format, type)
// into an enum yet so there's a default case here.
_ => unreachable!("Unsupported formats {:?} {:?}", format, data_type),
}
}
fn premultiply_inplace(format: TexFormat, data_type: TexDataType, pixels: &mut [u8]) {
match (format, data_type) {
(TexFormat::RGBA, TexDataType::UnsignedByte) => {
pixels::rgba8_premultiply_inplace(pixels);
},
(TexFormat::LuminanceAlpha, TexDataType::UnsignedByte) => {
for la in pixels.chunks_mut(2) {
la[0] = pixels::multiply_u8_color(la[0], la[1]);
}
},
(TexFormat::RGBA, TexDataType::UnsignedShort5551) => {
for rgba in pixels.chunks_mut(2) {
if NativeEndian::read_u16(rgba) & 1 == 0 {
NativeEndian::write_u16(rgba, 0);
}
}
},
(TexFormat::RGBA, TexDataType::UnsignedShort4444) => {
for rgba in pixels.chunks_mut(2) {
let pix = NativeEndian::read_u16(rgba);
let extend_to_8_bits = |val| (val | val << 4) as u8;
let r = extend_to_8_bits(pix >> 12 & 0x0f);
let g = extend_to_8_bits(pix >> 8 & 0x0f);
let b = extend_to_8_bits(pix >> 4 & 0x0f);
let a = extend_to_8_bits(pix & 0x0f);
NativeEndian::write_u16(
rgba,
((pixels::multiply_u8_color(r, a) & 0xf0) as u16) << 8 |
((pixels::multiply_u8_color(g, a) & 0xf0) as u16) << 4 |
((pixels::multiply_u8_color(b, a) & 0xf0) as u16) |
((a & 0x0f) as u16),
);
}
},
// Other formats don't have alpha, so return their data untouched.
_ => {},
}
}
fn unmultiply_inplace(pixels: &mut [u8]) {
for rgba in pixels.chunks_mut(4) {
let a = (rgba[3] as f32) / 255.0;
rgba[0] = (rgba[0] as f32 / a) as u8;
rgba[1] = (rgba[1] as f32 / a) as u8;
rgba[2] = (rgba[2] as f32 / a) as u8;
}
}
/// Flips the pixels in the Vec on the Y axis.
fn flip_pixels_y(
internal_format: TexFormat,
data_type: TexDataType,
width: usize,
height: usize,
unpacking_alignment: usize,
pixels: Vec<u8>,
) -> Vec<u8> {
let cpp = (data_type.element_size() * internal_format.components() /
data_type.components_per_element()) as usize;
let stride = (width * cpp + unpacking_alignment - 1) & !(unpacking_alignment - 1);
let mut flipped = Vec::<u8>::with_capacity(pixels.len());
for y in 0..height {
let flipped_y = height - 1 - y;
let start = flipped_y * stride;
flipped.extend_from_slice(&pixels[start..(start + width * cpp)]);
flipped.extend(vec![0u8; stride - width * cpp]);
}
flipped
}