From 7bc815448e025d677c94a750fb6c184ca9fe94c6 Mon Sep 17 00:00:00 2001
From: samcake <samuel.gateau@gmail.com>
Date: Wed, 16 Dec 2015 18:14:43 -0800
Subject: [PATCH] The material colors for diffuse and emissive are now gamma
 corrected by default

---
 libraries/model/src/model/Material.cpp |  8 ++++----
 libraries/model/src/model/Material.h   | 27 ++++++++++++++------------
 libraries/shared/src/ColorUtils.h      | 16 +++++++++++++++
 3 files changed, 35 insertions(+), 16 deletions(-)

diff --git a/libraries/model/src/model/Material.cpp b/libraries/model/src/model/Material.cpp
index c2ff828af3..1d0f6ee5d9 100755
--- a/libraries/model/src/model/Material.cpp
+++ b/libraries/model/src/model/Material.cpp
@@ -44,9 +44,9 @@ Material& Material::operator= (const Material& material) {
 Material::~Material() {
 }
 
-void Material::setDiffuse(const Color& diffuse) {
+void Material::setDiffuse(const Color& diffuse, bool isSRGB) {
     _key.setDiffuse(glm::any(glm::greaterThan(diffuse, Color(0.0f))));
-    _schemaBuffer.edit<Schema>()._diffuse = diffuse;
+    _schemaBuffer.edit<Schema>()._diffuse = (isSRGB ? ColorUtils::toLinearVec3(diffuse) : diffuse);
 }
 
 void Material::setMetallic(float metallic) {
@@ -54,9 +54,9 @@ void Material::setMetallic(float metallic) {
     _schemaBuffer.edit<Schema>()._metallic = glm::vec3(metallic);
 }
 
-void Material::setEmissive(const Color&  emissive) {
+void Material::setEmissive(const Color&  emissive, bool isSRGB) {
     _key.setEmissive(glm::any(glm::greaterThan(emissive, Color(0.0f))));
-    _schemaBuffer.edit<Schema>()._emissive = emissive;
+    _schemaBuffer.edit<Schema>()._emissive = (isSRGB ? ColorUtils::toLinearVec3(emissive) : emissive);
 }
 
 void Material::setGloss(float gloss) {
diff --git a/libraries/model/src/model/Material.h b/libraries/model/src/model/Material.h
index b0725d9908..bd1d45c7ed 100755
--- a/libraries/model/src/model/Material.h
+++ b/libraries/model/src/model/Material.h
@@ -14,7 +14,7 @@
 #include <bitset>
 #include <map>
 
-#include <glm/glm.hpp>
+#include <ColorUtils.h>
 
 #include <gpu/Resource.h>
 
@@ -219,28 +219,31 @@ public:
     virtual ~Material();
 
     const MaterialKey& getKey() const { return _key; }
-     
-    const Color& getEmissive() const { return _schemaBuffer.get<Schema>()._emissive; }
-    const Color& getDiffuse() const { return _schemaBuffer.get<Schema>()._diffuse; }
-    float getMetallic() const { return _schemaBuffer.get<Schema>()._metallic.x; }
-    float getGloss() const { return _schemaBuffer.get<Schema>()._gloss; }
-    float getOpacity() const { return _schemaBuffer.get<Schema>()._opacity; }
 
-    void setEmissive(const Color& emissive);
-    void setDiffuse(const Color& diffuse);
+    void setEmissive(const Color& emissive, bool isSRGB = true);
+    const Color& getEmissive(bool SRGB = true) const { return (SRGB ? ColorUtils::toGamma22Vec3(_schemaBuffer.get<Schema>()._emissive) : _schemaBuffer.get<Schema>()._emissive); }
+
+    void setDiffuse(const Color& diffuse, bool isSRGB = true);
+    const Color& getDiffuse(bool SRGB = true) const { return (SRGB ? ColorUtils::toGamma22Vec3(_schemaBuffer.get<Schema>()._diffuse) : _schemaBuffer.get<Schema>()._diffuse); }
+
     void setMetallic(float metallic);
+    float getMetallic() const { return _schemaBuffer.get<Schema>()._metallic.x; }
+
     void setGloss(float gloss);
+    float getGloss() const { return _schemaBuffer.get<Schema>()._gloss; }
+
     void setOpacity(float opacity);
+    float getOpacity() const { return _schemaBuffer.get<Schema>()._opacity; }
 
     // Schema to access the attribute values of the material
     class Schema {
     public:
         
-        Color _diffuse{0.5f};
+        glm::vec3 _diffuse{ 0.5f };
         float _opacity{1.f};
-        Color _metallic{0.03f};
+        glm::vec3 _metallic{ 0.03f };
         float _gloss{0.1f};
-        Color _emissive{0.0f};
+        glm::vec3 _emissive{ 0.0f };
         float _spare0{0.0f};
         glm::vec4  _spareVec4{0.0f}; // for alignment beauty, Material size == Mat4x4
 
diff --git a/libraries/shared/src/ColorUtils.h b/libraries/shared/src/ColorUtils.h
index 1ef8420cd7..b47e7c3a98 100644
--- a/libraries/shared/src/ColorUtils.h
+++ b/libraries/shared/src/ColorUtils.h
@@ -20,6 +20,10 @@
 class ColorUtils {
 public:
     inline static glm::vec3 toVec3(const xColor& color);
+
+    // Convert from gamma 2.2 space to linear
+    inline static glm::vec3 toLinearVec3(const glm::vec3& srgb);
+    inline static glm::vec3 toGamma22Vec3(const glm::vec3& linear);
 };
 
 inline glm::vec3 ColorUtils::toVec3(const xColor& color) {
@@ -27,4 +31,16 @@ inline glm::vec3 ColorUtils::toVec3(const xColor& color) {
     return glm::vec3(color.red * ONE_OVER_255, color.green * ONE_OVER_255, color.blue * ONE_OVER_255);
 }
 
+inline glm::vec3 ColorUtils::toLinearVec3(const glm::vec3& srgb) {
+    const float GAMMA_22 = 2.2f;
+    // Couldn't find glm::pow(vec3, vec3) ? so did it myself...
+    return glm::vec3(glm::pow(srgb.x, GAMMA_22), glm::pow(srgb.y, GAMMA_22), glm::pow(srgb.z, GAMMA_22));
+}
+
+inline glm::vec3 ColorUtils::toGamma22Vec3(const glm::vec3& linear) {
+    const float INV_GAMMA_22 = 1.0f / 2.2f;
+    // Couldn't find glm::pow(vec3, vec3) ? so did it myself...
+    return glm::vec3(glm::pow(linear.x, INV_GAMMA_22), glm::pow(linear.y, INV_GAMMA_22), glm::pow(linear.z, INV_GAMMA_22));
+}
+
 #endif // hifi_ColorUtils_h
\ No newline at end of file