From 39cae98850125f87575543dfef5ad0520fafef6e Mon Sep 17 00:00:00 2001
From: Hans-Kristian Arntzen <maister@archlinux.us>
Date: Mon, 1 Aug 2016 22:11:09 +0200
Subject: [PATCH] Add shader parameters to basic crt shaders.

---
 crt/common.inc      | 2 ++
 crt/linearize.slang | 4 +++-
 crt/parameters.inc  | 3 +++
 crt/scanline.slang  | 5 +++--
 4 files changed, 11 insertions(+), 3 deletions(-)
 create mode 100644 crt/parameters.inc

diff --git a/crt/common.inc b/crt/common.inc
index cdb99d2..6417dbf 100644
--- a/crt/common.inc
+++ b/crt/common.inc
@@ -2,5 +2,7 @@ layout(std140, set = 0, binding = 1) uniform UBO
 {
    mat4 MVP;
    vec4 SourceSize;
+   float OUT_GAMMA;
+   float BOOST;
 } global;
 
diff --git a/crt/linearize.slang b/crt/linearize.slang
index 763412c..c1fb2a3 100644
--- a/crt/linearize.slang
+++ b/crt/linearize.slang
@@ -1,8 +1,10 @@
 #version 450
+#include "parameters.inc"
 
 layout(std140, set = 0, binding = 0) uniform UBO
 {
    mat4 MVP;
+   float GAMMA;
 } global;
 
 #pragma stage vertex
@@ -23,7 +25,7 @@ layout(set = 0, binding = 2) uniform sampler2D Source;
 
 vec3 gamma(vec3 v)
 {
-   return pow(v, vec3(2.2));
+   return pow(v, vec3(global.GAMMA));
 }
 
 void main()
diff --git a/crt/parameters.inc b/crt/parameters.inc
new file mode 100644
index 0000000..e55bbb0
--- /dev/null
+++ b/crt/parameters.inc
@@ -0,0 +1,3 @@
+#pragma parameter OUT_GAMMA "Monitor Output Gamma" 2.2 1.8 2.4
+#pragma parameter BOOST "Color Boost" 1.0 0.2 2.0 0.02
+#pragma parameter GAMMA "CRT gamma" 2.5 2.0 3.0 0.02
diff --git a/crt/scanline.slang b/crt/scanline.slang
index 9427ea8..b0ac8f4 100644
--- a/crt/scanline.slang
+++ b/crt/scanline.slang
@@ -1,6 +1,7 @@
 #version 450
 
 #include "common.inc"
+#include "parameters.inc"
 
 #pragma stage vertex
 layout(location = 0) in vec4 Position;
@@ -20,7 +21,7 @@ layout(set = 0, binding = 2) uniform sampler2D Source;
 
 vec3 invgamma(vec3 v)
 {
-   return pow(v, vec3(1.0 / 2.2));
+   return pow(clamp(v, vec3(0.0), vec3(1.0)), vec3(1.0 / global.OUT_GAMMA));
 }
 
 float luma(vec3 col)
@@ -49,5 +50,5 @@ void main()
       dist.y * l1 +
       dist.z * l2;
 
-   FragColor = vec4(invgamma(color), 1.0);
+   FragColor = vec4(invgamma(global.BOOST * color), 1.0);
 }