color-management: make (ext_)srgb aliases for gamma22

src/gfx_apis/gl.rs

@@ -309,7 +309,7 @@ fn run_ops(fb: &Framebuffer, ops: &[GfxApiOpt]) -> Option<SyncFile> {
 }
 
 fn fill_boxes3(ctx: &GlRenderContext, boxes: &[[f32; 2]], color: &Color) {
-    let [r, g, b, a] = color.to_array(TransferFunction::Srgb);
+    let [r, g, b, a] = color.to_array(TransferFunction::Gamma22);
     let gles = ctx.ctx.dpy.gles;
     unsafe {
         (gles.glUseProgram)(ctx.fill_prog.prog);

src/gfx_apis/gl/renderer/framebuffer.rs

@@ -82,7 +82,7 @@ impl Framebuffer {
                 (gles.glBindFramebuffer)(GL_FRAMEBUFFER, self.gl.fbo);
                 (gles.glViewport)(0, 0, self.gl.width, self.gl.height);
                 if let Some(c) = clear {
-                    let [r, g, b, a] = c.to_array(TransferFunction::Srgb);
+                    let [r, g, b, a] = c.to_array(TransferFunction::Gamma22);
                     (gles.glClearColor)(r, g, b, a);
                     (gles.glClear)(GL_COLOR_BUFFER_BIT);
                 }

src/gfx_apis/vulkan/shaders/transfer_functions.glsl

@@ -3,60 +3,16 @@
 
 #include "frag_spec_const.glsl"
 
-#define TF_SRGB 0
 #define TF_LINEAR 1
 #define TF_ST2084_PQ 2
 #define TF_GAMMA24 3
 #define TF_GAMMA22 4
 #define TF_GAMMA28 5
 #define TF_ST240 6
-#define TF_EXT_SRGB 7
 #define TF_LOG100 8
 #define TF_LOG316 9
 #define TF_ST428 10
 
-vec3 eotf_srgb(vec3 c) {
-    return mix(
-        c * vec3(1.0 / 12.92),
-        pow((c + vec3(0.055)) / vec3(1.055), vec3(2.4)),
-        greaterThan(c, vec3(0.04045))
-    );
-}
-
-vec3 oetf_srgb(vec3 c) {
-    c = clamp(c, 0.0, 1.0);
-    return mix(
-        c * vec3(12.92),
-        vec3(1.055) * pow(c, vec3(1/2.4)) - vec3(0.055),
-        greaterThan(c, vec3(0.0031308))
-    );
-}
-
-vec3 eotf_ext_srgb(vec3 c) {
-    return mix(
-        -pow((c - vec3(0.055)) / vec3(-1.055), vec3(2.4)),
-        mix(
-            c * vec3(1.0 / 12.92),
-            pow((c + vec3(0.055)) / vec3(1.055), vec3(2.4)),
-            greaterThan(c, vec3(0.04045))
-        ),
-        greaterThan(c, vec3(-0.04045))
-    );
-}
-
-vec3 oetf_ext_srgb(vec3 c) {
-    c = clamp(c, -0.6038, 7.5913);
-    return mix(
-        vec3(-1.055) * pow(-c, vec3(1/2.4)) + vec3(0.055),
-        mix(
-            c * vec3(12.92),
-            vec3(1.055) * pow(c, vec3(1/2.4)) - vec3(0.055),
-            greaterThan(c, vec3(0.0031308))
-        ),
-        greaterThan(c, vec3(-0.0031308))
-    );
-}
-
 vec3 eotf_st2084_pq(vec3 c) {
     c = clamp(c, 0.0, 1.0);
     vec3 cp = pow(c, vec3(1.0 / 78.84375));
@@ -126,14 +82,12 @@ vec3 oetf_st428(vec3 c) {
 
 vec3 apply_eotf(vec3 c) {
     switch (eotf) {
-        case TF_SRGB: return eotf_srgb(c);
         case TF_LINEAR: return c;
         case TF_ST2084_PQ: return eotf_st2084_pq(c);
         case TF_GAMMA24: return sign(c) * pow(abs(c), vec3(2.4));
         case TF_GAMMA22: return sign(c) * pow(abs(c), vec3(2.2));
         case TF_GAMMA28: return sign(c) * pow(abs(c), vec3(2.8));
         case TF_ST240: return eotf_st240(c);
-        case TF_EXT_SRGB: return eotf_ext_srgb(c);
         case TF_LOG100: return eotf_log100(c);
         case TF_LOG316: return eotf_log316(c);
         case TF_ST428: return eotf_st428(c);
@@ -143,14 +97,12 @@ vec3 apply_eotf(vec3 c) {
 
 vec3 apply_oetf(vec3 c) {
     switch (oetf) {
-        case TF_SRGB: return oetf_srgb(c);
         case TF_LINEAR: return c;
         case TF_ST2084_PQ: return oetf_st2084_pq(c);
         case TF_GAMMA24: return sign(c) * pow(abs(c), vec3(1.0 / 2.4));
         case TF_GAMMA22: return sign(c) * pow(abs(c), vec3(1.0 / 2.2));
         case TF_GAMMA28: return sign(c) * pow(abs(c), vec3(1.0 / 2.8));
         case TF_ST240: return oetf_st240(c);
-        case TF_EXT_SRGB: return oetf_ext_srgb(c);
         case TF_LOG100: return oetf_log100(c);
         case TF_LOG316: return oetf_log316(c);
         case TF_ST428: return oetf_st428(c);

src/gfx_apis/vulkan/transfer_functions.rs

@@ -1,13 +1,11 @@
 use crate::cmm::cmm_transfer_function::TransferFunction;
 
-pub const TF_SRGB: u32 = 0;
 pub const TF_LINEAR: u32 = 1;
 pub const TF_ST2084_PQ: u32 = 2;
 pub const TF_GAMMA24: u32 = 3;
 pub const TF_GAMMA22: u32 = 4;
 pub const TF_GAMMA28: u32 = 5;
 pub const TF_ST240: u32 = 6;
-pub const TF_EXT_SRGB: u32 = 7;
 pub const TF_LOG100: u32 = 8;
 pub const TF_LOG316: u32 = 9;
 pub const TF_ST428: u32 = 10;
@@ -19,14 +17,12 @@ pub trait TransferFunctionExt: Sized {
 impl TransferFunctionExt for TransferFunction {
     fn to_vulkan(self) -> u32 {
         match self {
-            TransferFunction::Srgb => TF_SRGB,
             TransferFunction::Linear => TF_LINEAR,
             TransferFunction::St2084Pq => TF_ST2084_PQ,
             TransferFunction::Bt1886 => TF_GAMMA24,
             TransferFunction::Gamma22 => TF_GAMMA22,
             TransferFunction::Gamma28 => TF_GAMMA28,
             TransferFunction::St240 => TF_ST240,
-            TransferFunction::ExtSrgb => TF_EXT_SRGB,
             TransferFunction::Log100 => TF_LOG100,
             TransferFunction::Log316 => TF_LOG316,
             TransferFunction::St428 => TF_ST428,