blob: 96aef068e025cb277cf1f1a4b852801916dc5a30 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
|
#version 440
#extension GL_GOOGLE_include_directive : enable
#include "uniformbuffer.glsl"
#include "colortransfer.glsl"
#include "colorconvert.glsl"
#include "hdrtonemapper.glsl"
layout(location = 0) in vec2 texCoord;
layout(location = 0) out vec4 fragColor;
layout(binding = 1) uniform sampler2D plane1Texture;
layout(binding = 2) uniform sampler2D plane2Texture;
// This uses the PQ transfer function, see also https://en.wikipedia.org/wiki/Perceptual_quantizer
// or https://ieeexplore.ieee.org/document/7291452
//
// Tonemapping into the RGB range supported by the output is done using
// https://www.itu.int/dms_pub/itu-r/opb/rep/R-REP-BT.2390-6-2019-PDF-E.pdf, section 5.4
//
// masteringWhite in PQ values, not in linear. maxOutLum as defined in the doc above
// we assume that masteringBlack == 0, and minLum == 0 to simplify the calculations
//
// The calculation calculates a new luminosity in non linear space and scales the UV
// components before linearizing. This corresponds to option (2) at the end of section 5.4.
// This option was chosen as it keeps the colors correct while as well as being computationally
// cheapest.
void main()
{
float Y = texture(plane1Texture, texCoord).r;
vec2 UV = texture(plane2Texture, texCoord).rg;
// map to Rec.2020 color space
fragColor = vec4(Y, UV.x, UV.y, 1.);
fragColor = ubuf.colorMatrix * fragColor;
// tonemap
float y = (Y - 16./256.)*256./219.; // Video range (16...235)
float scale = tonemapScaleForLuminosity(y, ubuf.masteringWhite, ubuf.maxLum);
fragColor *= scale;
fragColor = convertPQToLinear(fragColor);
fragColor = convertRec2020ToSRGB(fragColor);
fragColor *= ubuf.opacity;
#ifndef QMM_OUTPUTSURFACE_LINEAR
fragColor = convertSRGBFromLinear(fragColor);
#endif
}
|
