Auto merge of #21660 - servo:webgl, r=jdm

Some more drive-by fixes for rgba8_image_to_tex_image_data

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bors-servo 2018-09-10 19:21:45 -04:00 committed by GitHub
commit b0ee750fba
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@ -4017,14 +4017,15 @@ fn rgba8_image_to_tex_image_data(
match (format, data_type) {
(TexFormat::RGBA, TexDataType::UnsignedByte) => pixels,
(TexFormat::RGB, TexDataType::UnsignedByte) => {
// Remove alpha channel
let mut rgb8 = Vec::<u8>::with_capacity(pixel_count * 3);
for rgba8 in pixels.chunks(4) {
rgb8.push(rgba8[0]);
rgb8.push(rgba8[1]);
rgb8.push(rgba8[2]);
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);
}
rgb8
pixels.truncate(pixel_count * 3);
pixels
},
(TexFormat::Alpha, TexDataType::UnsignedByte) => {
for i in 0..pixel_count {
@ -4126,8 +4127,8 @@ fn rgba8_image_to_tex_image_data(
(TexFormat::Luminance, TexDataType::Float) => {
for rgba8 in pixels.chunks_mut(4) {
let p = luminance(rgba8[0], rgba8[1], rgba8[2]);
NativeEndian::write_f32(rgba8, p as f32);
let p = rgba8[0] as f32;
NativeEndian::write_f32(rgba8, p);
}
pixels
},
@ -4135,8 +4136,7 @@ fn rgba8_image_to_tex_image_data(
(TexFormat::LuminanceAlpha, TexDataType::Float) => {
let mut data = Vec::<u8>::with_capacity(pixel_count * 8);
for rgba8 in pixels.chunks(4) {
let p = luminance(rgba8[0], rgba8[1], rgba8[2]);
data.write_f32::<NativeEndian>(p as f32).unwrap();
data.write_f32::<NativeEndian>(rgba8[0] as f32).unwrap();
data.write_f32::<NativeEndian>(rgba8[3] as f32).unwrap();
}
data
@ -4172,23 +4172,20 @@ fn rgba8_image_to_tex_image_data(
},
(TexFormat::Luminance, TexDataType::HalfFloat) => {
for i in 0..pixel_count {
let p = {
let rgb = &pixels[i * 4..i * 4 + 3];
f16::from_f32(luminance(rgb[0], rgb[1], rgb[2]) as f32).as_bits()
};
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) => {
let mut data = Vec::<u8>::with_capacity(pixel_count * 8);
for rgba8 in pixels.chunks(4) {
let p = luminance(rgba8[0], rgba8[1], rgba8[2]);
data.write_u16::<NativeEndian>(f16::from_f32(p as f32).as_bits()).unwrap();
data.write_u16::<NativeEndian>(f16::from_f32(rgba8[3] as f32).as_bits()).unwrap();
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);
}
data
pixels
},
// Validation should have ensured that we only hit the
@ -4197,11 +4194,3 @@ fn rgba8_image_to_tex_image_data(
_ => unreachable!("Unsupported formats {:?} {:?}", format, data_type)
}
}
// https://en.wikipedia.org/wiki/Relative_luminance
#[inline]
fn luminance(r: u8, g: u8, b: u8) -> u8 {
(0.2126 * (r as f32) +
0.7152 * (g as f32) +
0.0722 * (b as f32)) as u8
}