vulkan: rewrite shaders in terms of eotf and oetf

src/gfx_apis/vulkan.rs

@@ -17,6 +17,7 @@ mod shaders;
 mod shm_image;
 mod staging;
 mod transfer;
+mod transfer_functions;
 
 use {
     crate::{

src/gfx_apis/vulkan/pipeline.rs

@@ -39,7 +39,8 @@ pub(super) struct PipelineCreateInfo {
     pub(super) blend: bool,
     pub(super) src_has_alpha: bool,
     pub(super) has_alpha_mult: bool,
-    pub(super) with_linear_output: bool,
+    pub(super) eotf: u32,
+    pub(super) oetf: u32,
     pub(super) frag_descriptor_set_layout: Option<Rc<VulkanDescriptorSetLayout>>,
 }
 
@@ -77,8 +78,8 @@ impl VulkanDevice {
         };
         let destroy_layout =
             OnDrop(|| unsafe { self.device.destroy_pipeline_layout(pipeline_layout, None) });
-        let mut frag_spec_data = ArrayVec::<_, { 3 * 4 }>::new();
-        let mut frag_spec_entries = ArrayVec::<_, 3>::new();
+        let mut frag_spec_data = ArrayVec::<_, { 4 * 4 }>::new();
+        let mut frag_spec_entries = ArrayVec::<_, 4>::new();
         let mut frag_spec_entry = |data: &[u8]| {
             let entry = SpecializationMapEntry::default()
                 .constant_id(frag_spec_entries.len() as _)
@@ -89,7 +90,8 @@ impl VulkanDevice {
         };
         frag_spec_entry(&(info.src_has_alpha as u32).to_ne_bytes());
         frag_spec_entry(&(info.has_alpha_mult as u32).to_ne_bytes());
-        frag_spec_entry(&(info.with_linear_output as u32).to_ne_bytes());
+        frag_spec_entry(&info.eotf.to_ne_bytes());
+        frag_spec_entry(&info.oetf.to_ne_bytes());
         let frag_spec = SpecializationInfo::default()
             .map_entries(&frag_spec_entries)
             .data(&frag_spec_data);

src/gfx_apis/vulkan/renderer.rs

@@ -26,6 +26,7 @@ use {
                 LEGACY_TEX_FRAG, LEGACY_TEX_VERT, OUT_FRAG, OUT_VERT, OutPushConstants, TEX_FRAG,
                 TEX_VERT, TexPushConstants, VulkanShader,
             },
+            transfer_functions::{TF_LINEAR, TF_SRGB},
         },
         io_uring::IoUring,
         rect::{Rect, Region},
@@ -305,7 +306,10 @@ impl VulkanRenderer {
         format: vk::Format,
         pass: RenderPass,
     ) -> Result<Rc<VulkanFormatPipelines>, VulkanError> {
-        let with_linear_output = pass == RenderPass::BlendBuffer;
+        let (eotf, oetf) = match pass {
+            RenderPass::BlendBuffer => (TF_SRGB, TF_LINEAR),
+            RenderPass::FrameBuffer => (TF_SRGB, TF_SRGB),
+        };
         let pipelines = &self.pipelines[pass];
         if let Some(pl) = pipelines.get(&format) {
             return Ok(pl);
@@ -319,7 +323,8 @@ impl VulkanRenderer {
                     blend: src_has_alpha,
                     src_has_alpha,
                     has_alpha_mult: false,
-                    with_linear_output,
+                    eotf,
+                    oetf,
                     frag_descriptor_set_layout: None,
                 })
         };
@@ -334,7 +339,8 @@ impl VulkanRenderer {
                     blend: src_has_alpha || has_alpha_mult,
                     src_has_alpha,
                     has_alpha_mult,
-                    with_linear_output,
+                    eotf,
+                    oetf,
                     frag_descriptor_set_layout: Some(self.tex_descriptor_set_layout.clone()),
                 })
         };
@@ -847,7 +853,8 @@ impl VulkanRenderer {
                         blend: false,
                         src_has_alpha: true,
                         has_alpha_mult: false,
-                        with_linear_output: true,
+                        eotf: TF_LINEAR,
+                        oetf: TF_SRGB,
                         frag_descriptor_set_layout: Some(layout.clone()),
                     })?;
                 e.insert(out.clone());

src/gfx_apis/vulkan/shaders/frag_spec_const.glsl

@@ -3,6 +3,7 @@
 
 layout(constant_id = 0) const bool src_has_alpha = false;
 layout(constant_id = 1) const bool has_alpha_multiplier = false;
-layout(constant_id = 2) const bool color_management = false;
+layout(constant_id = 2) const uint eotf = 0;
+layout(constant_id = 3) const uint oetf = 0;
 
 #endif

src/gfx_apis/vulkan/shaders/out.frag

@@ -10,8 +10,11 @@ layout(location = 0) out vec4 out_color;
 
 void main() {
 	vec4 c = texelFetch(in_color, ivec2(gl_FragCoord.xy), 0);
-	c.rgb /= mix(c.a, 1.0, c.a == 0.0);
-	c.rgb = oetf_srgb(c.rgb);
-	c.rgb *= c.a;
+	if (eotf != oetf) {
+		c.rgb /= mix(c.a, 1.0, c.a == 0.0);
+		c.rgb = apply_eotf(c.rgb);
+		c.rgb = apply_oetf(c.rgb);
+		c.rgb *= c.a;
+	}
 	out_color = c;
 }

src/gfx_apis/vulkan/shaders/tex.frag

@@ -10,11 +10,12 @@ layout(location = 0) out vec4 out_color;
 
 void main() {
 	vec4 c = textureLod(tex, tex_pos, 0);
-	if (color_management) {
+	if (eotf != oetf) {
 		if (src_has_alpha) {
 			c.rgb /= mix(c.a, 1.0, c.a == 0.0);
 		}
-		c.rgb = eotf_srgb(c.rgb);
+		c.rgb = apply_eotf(c.rgb);
+		c.rgb = apply_oetf(c.rgb);
 		if (src_has_alpha) {
 			c.rgb *= c.a;
 		}

src/gfx_apis/vulkan/shaders/transfer_functions.glsl

@@ -1,6 +1,11 @@
 #ifndef TRANSFER_FUNCTIONS_GLSL
 #define TRANSFER_FUNCTIONS_GLSL
 
+#include "frag_spec_const.glsl"
+
+#define SRGB 0
+#define LINEAR 1
+
 vec3 eotf_srgb(vec3 c) {
     return mix(
         c * vec3(1.0 / 12.92),
@@ -18,4 +23,20 @@ vec3 oetf_srgb(vec3 c) {
     );
 }
 
+vec3 apply_eotf(vec3 c) {
+    switch (eotf) {
+        case SRGB: return eotf_srgb(c);
+        case LINEAR: return c;
+        default: return c;
+    }
+}
+
+vec3 apply_oetf(vec3 c) {
+    switch (oetf) {
+        case SRGB: return oetf_srgb(c);
+        case LINEAR: return c;
+        default: return c;
+    }
+}
+
 #endif

src/gfx_apis/vulkan/transfer_functions.rs

@@ -0,0 +1,2 @@
+pub const TF_SRGB: u32 = 0;
+pub const TF_LINEAR: u32 = 1;