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Make rgba8_image_to_tex_image_data a free-standing function
This commit is contained in:
Anthony Ramine
parent
a5f9d03229
commit
145086e150
1 changed files with 202 additions and 201 deletions
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@ -481,206 +481,6 @@ impl WebGLRenderingContext {
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}
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}
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}
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}
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// https://en.wikipedia.org/wiki/Relative_luminance
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#[inline]
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fn luminance(r: u8, g: u8, b: u8) -> u8 {
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(0.2126 * (r as f32) +
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0.7152 * (g as f32) +
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0.0722 * (b as f32)) as u8
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}
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/// Translates an image in rgba8 (red in the first byte) format to
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/// the format that was requested of TexImage.
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///
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/// From the WebGL 1.0 spec, 5.14.8:
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///
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/// "The source image data is conceptually first converted to
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/// the data type and format specified by the format and type
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/// arguments, and then transferred to the WebGL
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/// implementation. If a packed pixel format is specified
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/// which would imply loss of bits of precision from the image
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/// data, this loss of precision must occur."
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fn rgba8_image_to_tex_image_data(&self,
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format: TexFormat,
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data_type: TexDataType,
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pixels: Vec<u8>) -> Vec<u8> {
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// hint for vector allocation sizing.
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let pixel_count = pixels.len() / 4;
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match (format, data_type) {
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(TexFormat::RGBA, TexDataType::UnsignedByte) => pixels,
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(TexFormat::RGB, TexDataType::UnsignedByte) => {
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// Remove alpha channel
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let mut rgb8 = Vec::<u8>::with_capacity(pixel_count * 3);
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for rgba8 in pixels.chunks(4) {
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rgb8.push(rgba8[0]);
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rgb8.push(rgba8[1]);
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rgb8.push(rgba8[2]);
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}
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rgb8
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},
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(TexFormat::Alpha, TexDataType::UnsignedByte) => {
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let mut alpha = Vec::<u8>::with_capacity(pixel_count);
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for rgba8 in pixels.chunks(4) {
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alpha.push(rgba8[3]);
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}
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alpha
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},
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(TexFormat::Luminance, TexDataType::UnsignedByte) => {
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let mut luminance = Vec::<u8>::with_capacity(pixel_count);
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for rgba8 in pixels.chunks(4) {
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luminance.push(Self::luminance(rgba8[0], rgba8[1], rgba8[2]));
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}
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luminance
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},
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(TexFormat::LuminanceAlpha, TexDataType::UnsignedByte) => {
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let mut data = Vec::<u8>::with_capacity(pixel_count * 2);
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for rgba8 in pixels.chunks(4) {
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data.push(Self::luminance(rgba8[0], rgba8[1], rgba8[2]));
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data.push(rgba8[3]);
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}
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data
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},
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(TexFormat::RGBA, TexDataType::UnsignedShort4444) => {
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let mut rgba4 = Vec::<u8>::with_capacity(pixel_count * 2);
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for rgba8 in pixels.chunks(4) {
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rgba4.write_u16::<NativeEndian>((rgba8[0] as u16 & 0xf0) << 8 |
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(rgba8[1] as u16 & 0xf0) << 4 |
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(rgba8[2] as u16 & 0xf0) |
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(rgba8[3] as u16 & 0xf0) >> 4).unwrap();
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}
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rgba4
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}
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(TexFormat::RGBA, TexDataType::UnsignedShort5551) => {
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let mut rgba5551 = Vec::<u8>::with_capacity(pixel_count * 2);
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for rgba8 in pixels.chunks(4) {
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rgba5551.write_u16::<NativeEndian>((rgba8[0] as u16 & 0xf8) << 8 |
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(rgba8[1] as u16 & 0xf8) << 3 |
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(rgba8[2] as u16 & 0xf8) >> 2 |
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(rgba8[3] as u16) >> 7).unwrap();
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}
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rgba5551
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}
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(TexFormat::RGB, TexDataType::UnsignedShort565) => {
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let mut rgb565 = Vec::<u8>::with_capacity(pixel_count * 2);
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for rgba8 in pixels.chunks(4) {
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rgb565.write_u16::<NativeEndian>((rgba8[0] as u16 & 0xf8) << 8 |
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(rgba8[1] as u16 & 0xfc) << 3 |
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(rgba8[2] as u16 & 0xf8) >> 3).unwrap();
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}
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rgb565
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}
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(TexFormat::RGBA, TexDataType::Float) => {
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let mut rgbaf32 = Vec::<u8>::with_capacity(pixel_count * 16);
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for rgba8 in pixels.chunks(4) {
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rgbaf32.write_f32::<NativeEndian>(rgba8[0] as f32).unwrap();
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rgbaf32.write_f32::<NativeEndian>(rgba8[1] as f32).unwrap();
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rgbaf32.write_f32::<NativeEndian>(rgba8[2] as f32).unwrap();
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rgbaf32.write_f32::<NativeEndian>(rgba8[3] as f32).unwrap();
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}
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rgbaf32
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}
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(TexFormat::RGB, TexDataType::Float) => {
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let mut rgbf32 = Vec::<u8>::with_capacity(pixel_count * 12);
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for rgba8 in pixels.chunks(4) {
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rgbf32.write_f32::<NativeEndian>(rgba8[0] as f32).unwrap();
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rgbf32.write_f32::<NativeEndian>(rgba8[1] as f32).unwrap();
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rgbf32.write_f32::<NativeEndian>(rgba8[2] as f32).unwrap();
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}
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rgbf32
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}
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(TexFormat::Alpha, TexDataType::Float) => {
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let mut alpha = Vec::<u8>::with_capacity(pixel_count * 4);
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for rgba8 in pixels.chunks(4) {
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alpha.write_f32::<NativeEndian>(rgba8[0] as f32).unwrap();
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}
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alpha
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},
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(TexFormat::Luminance, TexDataType::Float) => {
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let mut luminance = Vec::<u8>::with_capacity(pixel_count * 4);
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for rgba8 in pixels.chunks(4) {
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let p = Self::luminance(rgba8[0], rgba8[1], rgba8[2]);
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luminance.write_f32::<NativeEndian>(p as f32).unwrap();
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}
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luminance
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},
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(TexFormat::LuminanceAlpha, TexDataType::Float) => {
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let mut data = Vec::<u8>::with_capacity(pixel_count * 8);
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for rgba8 in pixels.chunks(4) {
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let p = Self::luminance(rgba8[0], rgba8[1], rgba8[2]);
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data.write_f32::<NativeEndian>(p as f32).unwrap();
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data.write_f32::<NativeEndian>(rgba8[3] as f32).unwrap();
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}
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data
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},
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(TexFormat::RGBA, TexDataType::HalfFloat) => {
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let mut rgbaf16 = Vec::<u8>::with_capacity(pixel_count * 8);
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for rgba8 in pixels.chunks(4) {
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rgbaf16.write_u16::<NativeEndian>(f16::from_f32(rgba8[0] as f32).as_bits()).unwrap();
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rgbaf16.write_u16::<NativeEndian>(f16::from_f32(rgba8[1] as f32).as_bits()).unwrap();
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rgbaf16.write_u16::<NativeEndian>(f16::from_f32(rgba8[2] as f32).as_bits()).unwrap();
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rgbaf16.write_u16::<NativeEndian>(f16::from_f32(rgba8[3] as f32).as_bits()).unwrap();
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}
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rgbaf16
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},
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(TexFormat::RGB, TexDataType::HalfFloat) => {
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let mut rgbf16 = Vec::<u8>::with_capacity(pixel_count * 6);
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for rgba8 in pixels.chunks(4) {
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rgbf16.write_u16::<NativeEndian>(f16::from_f32(rgba8[0] as f32).as_bits()).unwrap();
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rgbf16.write_u16::<NativeEndian>(f16::from_f32(rgba8[1] as f32).as_bits()).unwrap();
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rgbf16.write_u16::<NativeEndian>(f16::from_f32(rgba8[2] as f32).as_bits()).unwrap();
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}
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rgbf16
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},
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(TexFormat::Alpha, TexDataType::HalfFloat) => {
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let mut alpha = Vec::<u8>::with_capacity(pixel_count * 2);
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for rgba8 in pixels.chunks(4) {
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alpha.write_u16::<NativeEndian>(f16::from_f32(rgba8[3] as f32).as_bits()).unwrap();
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}
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alpha
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},
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(TexFormat::Luminance, TexDataType::HalfFloat) => {
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let mut luminance = Vec::<u8>::with_capacity(pixel_count * 4);
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for rgba8 in pixels.chunks(4) {
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let p = Self::luminance(rgba8[0], rgba8[1], rgba8[2]);
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luminance.write_u16::<NativeEndian>(f16::from_f32(p as f32).as_bits()).unwrap();
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}
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luminance
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},
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(TexFormat::LuminanceAlpha, TexDataType::HalfFloat) => {
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let mut data = Vec::<u8>::with_capacity(pixel_count * 8);
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for rgba8 in pixels.chunks(4) {
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let p = Self::luminance(rgba8[0], rgba8[1], rgba8[2]);
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data.write_u16::<NativeEndian>(f16::from_f32(p as f32).as_bits()).unwrap();
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data.write_u16::<NativeEndian>(f16::from_f32(rgba8[3] as f32).as_bits()).unwrap();
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}
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data
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},
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// Validation should have ensured that we only hit the
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// above cases, but we haven't turned the (format, type)
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// into an enum yet so there's a default case here.
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_ => unreachable!("Unsupported formats {:?} {:?}", format, data_type)
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}
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}
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fn get_image_pixels(
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fn get_image_pixels(
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&self,
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&self,
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source: ImageDataOrHTMLImageElementOrHTMLCanvasElementOrHTMLVideoElement,
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source: ImageDataOrHTMLImageElementOrHTMLCanvasElementOrHTMLVideoElement,
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@ -893,7 +693,7 @@ impl WebGLRenderingContext {
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}
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}
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if source_from_image_or_canvas {
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if source_from_image_or_canvas {
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pixels = self.rgba8_image_to_tex_image_data(internal_format, data_type, pixels);
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pixels = rgba8_image_to_tex_image_data(internal_format, data_type, pixels);
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}
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}
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// FINISHME: Consider doing premultiply and flip in a single mutable Vec.
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// FINISHME: Consider doing premultiply and flip in a single mutable Vec.
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@ -4193,3 +3993,204 @@ fn remove_premultiplied_alpha(pixels: &mut [u8]) {
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rgba[2] = (rgba[2] as f32 / a) as u8;
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rgba[2] = (rgba[2] as f32 / a) as u8;
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}
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}
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}
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}
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/// Translates an image in rgba8 (red in the first byte) format to
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/// the format that was requested of TexImage.
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///
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/// From the WebGL 1.0 spec, 5.14.8:
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///
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/// "The source image data is conceptually first converted to
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/// the data type and format specified by the format and type
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/// arguments, and then transferred to the WebGL
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/// implementation. If a packed pixel format is specified
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/// which would imply loss of bits of precision from the image
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/// data, this loss of precision must occur."
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fn rgba8_image_to_tex_image_data(
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format: TexFormat,
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data_type: TexDataType,
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pixels: Vec<u8>,
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) -> Vec<u8> {
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// hint for vector allocation sizing.
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let pixel_count = pixels.len() / 4;
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match (format, data_type) {
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(TexFormat::RGBA, TexDataType::UnsignedByte) => pixels,
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(TexFormat::RGB, TexDataType::UnsignedByte) => {
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// Remove alpha channel
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let mut rgb8 = Vec::<u8>::with_capacity(pixel_count * 3);
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for rgba8 in pixels.chunks(4) {
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rgb8.push(rgba8[0]);
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rgb8.push(rgba8[1]);
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rgb8.push(rgba8[2]);
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}
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rgb8
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},
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(TexFormat::Alpha, TexDataType::UnsignedByte) => {
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let mut alpha = Vec::<u8>::with_capacity(pixel_count);
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for rgba8 in pixels.chunks(4) {
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alpha.push(rgba8[3]);
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}
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alpha
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},
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(TexFormat::Luminance, TexDataType::UnsignedByte) => {
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let mut lum = Vec::<u8>::with_capacity(pixel_count);
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for rgba8 in pixels.chunks(4) {
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lum.push(luminance(rgba8[0], rgba8[1], rgba8[2]));
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}
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lum
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},
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(TexFormat::LuminanceAlpha, TexDataType::UnsignedByte) => {
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let mut data = Vec::<u8>::with_capacity(pixel_count * 2);
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for rgba8 in pixels.chunks(4) {
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data.push(luminance(rgba8[0], rgba8[1], rgba8[2]));
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data.push(rgba8[3]);
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}
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data
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},
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(TexFormat::RGBA, TexDataType::UnsignedShort4444) => {
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let mut rgba4 = Vec::<u8>::with_capacity(pixel_count * 2);
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for rgba8 in pixels.chunks(4) {
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rgba4.write_u16::<NativeEndian>((rgba8[0] as u16 & 0xf0) << 8 |
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(rgba8[1] as u16 & 0xf0) << 4 |
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(rgba8[2] as u16 & 0xf0) |
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(rgba8[3] as u16 & 0xf0) >> 4).unwrap();
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}
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rgba4
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}
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(TexFormat::RGBA, TexDataType::UnsignedShort5551) => {
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let mut rgba5551 = Vec::<u8>::with_capacity(pixel_count * 2);
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for rgba8 in pixels.chunks(4) {
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rgba5551.write_u16::<NativeEndian>((rgba8[0] as u16 & 0xf8) << 8 |
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(rgba8[1] as u16 & 0xf8) << 3 |
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(rgba8[2] as u16 & 0xf8) >> 2 |
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(rgba8[3] as u16) >> 7).unwrap();
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}
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rgba5551
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}
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(TexFormat::RGB, TexDataType::UnsignedShort565) => {
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let mut rgb565 = Vec::<u8>::with_capacity(pixel_count * 2);
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for rgba8 in pixels.chunks(4) {
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rgb565.write_u16::<NativeEndian>((rgba8[0] as u16 & 0xf8) << 8 |
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(rgba8[1] as u16 & 0xfc) << 3 |
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(rgba8[2] as u16 & 0xf8) >> 3).unwrap();
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}
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rgb565
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}
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(TexFormat::RGBA, TexDataType::Float) => {
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let mut rgbaf32 = Vec::<u8>::with_capacity(pixel_count * 16);
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for rgba8 in pixels.chunks(4) {
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rgbaf32.write_f32::<NativeEndian>(rgba8[0] as f32).unwrap();
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rgbaf32.write_f32::<NativeEndian>(rgba8[1] as f32).unwrap();
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rgbaf32.write_f32::<NativeEndian>(rgba8[2] as f32).unwrap();
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rgbaf32.write_f32::<NativeEndian>(rgba8[3] as f32).unwrap();
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}
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rgbaf32
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}
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(TexFormat::RGB, TexDataType::Float) => {
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let mut rgbf32 = Vec::<u8>::with_capacity(pixel_count * 12);
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for rgba8 in pixels.chunks(4) {
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rgbf32.write_f32::<NativeEndian>(rgba8[0] as f32).unwrap();
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rgbf32.write_f32::<NativeEndian>(rgba8[1] as f32).unwrap();
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||||||
|
rgbf32.write_f32::<NativeEndian>(rgba8[2] as f32).unwrap();
|
||||||
|
}
|
||||||
|
rgbf32
|
||||||
|
}
|
||||||
|
|
||||||
|
(TexFormat::Alpha, TexDataType::Float) => {
|
||||||
|
let mut alpha = Vec::<u8>::with_capacity(pixel_count * 4);
|
||||||
|
for rgba8 in pixels.chunks(4) {
|
||||||
|
alpha.write_f32::<NativeEndian>(rgba8[0] as f32).unwrap();
|
||||||
|
}
|
||||||
|
alpha
|
||||||
|
},
|
||||||
|
|
||||||
|
(TexFormat::Luminance, TexDataType::Float) => {
|
||||||
|
let mut lum = Vec::<u8>::with_capacity(pixel_count * 4);
|
||||||
|
for rgba8 in pixels.chunks(4) {
|
||||||
|
let p = luminance(rgba8[0], rgba8[1], rgba8[2]);
|
||||||
|
luminance.write_f32::<NativeEndian>(p as f32).unwrap();
|
||||||
|
}
|
||||||
|
luminance
|
||||||
|
},
|
||||||
|
|
||||||
|
(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[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) => {
|
||||||
|
let mut alpha = Vec::<u8>::with_capacity(pixel_count * 2);
|
||||||
|
for rgba8 in pixels.chunks(4) {
|
||||||
|
alpha.write_u16::<NativeEndian>(f16::from_f32(rgba8[3] as f32).as_bits()).unwrap();
|
||||||
|
}
|
||||||
|
alpha
|
||||||
|
},
|
||||||
|
|
||||||
|
(TexFormat::Luminance, TexDataType::HalfFloat) => {
|
||||||
|
let mut lum = Vec::<u8>::with_capacity(pixel_count * 4);
|
||||||
|
for rgba8 in pixels.chunks(4) {
|
||||||
|
let p = luminance(rgba8[0], rgba8[1], rgba8[2]);
|
||||||
|
lum.write_u16::<NativeEndian>(f16::from_f32(p as f32).as_bits()).unwrap();
|
||||||
|
}
|
||||||
|
lum
|
||||||
|
},
|
||||||
|
|
||||||
|
(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();
|
||||||
|
}
|
||||||
|
data
|
||||||
|
},
|
||||||
|
|
||||||
|
// 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)
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
// 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
|
||||||
|
}
|
||||||
|
|
|
||||||
Loading…
Add table
Add a link
Reference in a new issue